Document bQyE2BbLe6aYNMERwr32OjB1

BULLETIN NO. PCE-003 DATE 3/80 1978 350L CHEVROLET HEAD In 1978, Chevrolet made a modification to the heads of the 350L engine. Although the modification was slight, the beaded steel head gasket designed for the 1977 & earlier 350L engines will not work on the 1978 engines. The heads will not crush the entire sealing bead of the earlier style head gasket. The new style heads are also being sold as replacement heads for the earlier 350L engines, so there is a chance that a beaded steel head gasket will not work even on an engine for which it was originally designed. To eliminate any chance of leakage on 1978 350L engines or older 350L engines with replacement heads on them, use the Victocor head gasket. This gasket will work on all 350L Chevrolet engines, even those with replacement heads. -- Victocor Head gasket 1956-78 ______ ___ SCF-NAPA-1575 BULLETIN NO. PCE-005 DATE 7/80 DIESEL ENGINE HEAD GASKET LEAKS DIESEL ENGINE HEAD GASKET LEAKS (GM's passenger car diesel engines) It has come to our attention that many of the diesel engines are experiencing head gasket leakage problems. After the problem has been diagnosed, replace the head gasket with Victor No. 3568. A word of caution - the 350 Cl D diesel head cannot have more than .010" removed becauseof the tightvalveto piston clearance. Caution should also be taken when installing the pre-chamber- it must not be recessed in the head more than .005" and it must not protrude more than .003". If a compression test is used to determine that the head gasket is leaking there should not be a 70% difference between the highest and lowest cylinderand no cylinder reading should be less than 275 pounds. Check the manufacturer's recommendations before making any checks or tests. V 43 BULLETIN NO. PCE-006 DATE 3/81 HEAD GASKET INSTALLATION HEAD GASKET INSTALLATION Two of the most common errors of head gasket installation are easy to avoid. Overtorque Torque specs for each engine are carefully calculated according to head bolt size, number of head bolts, and required loads for gasket sealing. Some head gaskets have fire rings that can be damaged. Overtorque can also cause uneven bolt loads. This can lead to warped heads and leaking valve seats. Reusing Head Bolts 1. Head bolts stretch and lose some of their strength after a period of time. Stretched head bolts may bottom in the block, break, or give a false torque reading. 2. Different length head bolts may be found on the same engine. Also, pay special attention to bolts that are relieved or drilled for oil flow. 3. Be sure to inspect and "chase" the threads in the block before installing head bolts. 4. Lightly coat the new bolts with anti-seize compound or motor oil before installation. 5. Follow the manufacturer's recommended pattern of bolt tightening. Tighten the bolts in increments, but only up to the recommended torque specifications. iI 45 BULLETIN NO. PCE-008 DATE 3/81 NEW VICTOR EXTRA HIGH TEMPERATURE VALVE COVER GASKET NEW VICTOR EXTRA HIGH TEMPERATURE VALVE COVER"GASKET Victor now has available an optional High Temperature Valve Cover Gasket for "Extra High Temperature Applications". This new "Extra High Temperature Application" valve cover gasket is manufactured of Polyacrylic Cork-Rubber which will withstand temperatures of over 375 F Degrees. The top 12 numbers will carry the suffix "H" after the valve cover gasket number (EXAMPLE: VS-38322H), to indicate "High Temperature Application". These 12 numbers will give you coverage on 70% of all American made passenger cars, light trucks, vans and recreational vehicles. 49 BULLETIN NO. PCE-009 DATE 4/81 CHEVROLET SMALL BLOCK V8 INTAKE MANIFOLD GASKETS CHEVROLET SMALL BLOCK V8 INTAKE MANIFOLD GASKETS Chevrolet Division has advised their dealers that intake manifold gasket leakage can occur on 1978-81 305, 350 & 400 C.I.D. engines with 4 Bbl. carburetors when used in severe operation under high loads and/or speeds. High temperature around the E.G.R. valve can cause the gasket to deteriorate and permit engine oil to be drawn into numbers 2, 4, 6 & 8 cylinders. This is to advise that we will soon have available an optional manifold set, MS15315, which contains gaskets manufactured with a polyacrylic compound for high temperature resistance. These gaskets will be black in color as opposed to the red MS15183 and will be cataloged as a high temperature option in our 1981 Master Gasket Catalog. Also, the stainless steel heat crossover restrictor plate has been removed from the crossover ports in the R.H. manifold gasket contained in MSI 5183. This set now contains two identical gaskets, both with the heat crossover ports open. The two stainless steel restrictor plates and related instruction sheet have been removed from all related head and full sets. This was done because Chevrolet has discontinued the restricted manifold gaskets and is not related to the above heat problem. 51 BULLETIN NO. PCE-010 DATE 4/81 VW DIESEL CYLINDER HEAD GASKET VW DIESEL CYLINDER HEAD GASKET In order to compensate for manufacturing tolerances on the Rabbit Diesel Engine, VW uses four different thicknesses of head gaskets. The different gaskets are identified by grooves cut into a tab on the side of the gasket as shown below. Be sure to order the same gasket as the one you removed. 2 Grooves -- 1:30 mm 3 Grooves -- 1:45 mm 4 Grooves -- 1:50 mm 5 Grooves -- 1:60 mm -- Victor Part no. 3666 -- ..................... 3664 -- ..................... 3669 -- ..................... 3665 The replacement gaskets are coated with a wax sealant and packaged in an airtight poly bag. The gasket "cures" after installation, so leave it in the bag until you are ready to install it. No additional sealers should be used. Be sure to torque the head bolts to OEM specifications. -i BULLETIN NO. PCE-012 DATE 5/81 GASKET INSTALLATION IS THE KEY TO GOOD PERFORMANCE GASKET INSTALLATION IS THE KEY TO GOOD PERFORMANCE By Russel Reicheri Product Engineer At one time or another, every mech anic is bound to run into a sealing problem. However, you can pinpoint your problems and minimize them in the long run by following a few simple steps when resealing an en gine. Just as there' are different gas kets and materials for different applications, there ' are procedures and techniques unique to each type of gasket. The following are a few basics on how to do a good resealing job. The master key to good perfor mance is The Cylinder Head Gasket. It must seal water, oil and combus tion gas pressure up to 1000 PSI in automotive applications. The head gasket must perform in temperature extremes from -40SF. to +1300"F This critical component must also be resistant to any erosion or chemical effects of various coolants and addi tives. . An improperly installed cylinder head gasket is as ineffective as no gasket at all. The correct installation of the head gasket is a critical step in the engine reassembly procedure and is of prime importance to the operation of an engine. The follow ing procedure is recommended: Inspect the condition of all mating surfaces. Check closely for irregu larities, block distortion and head warpage. Use a flat stock straight edge and feeler gauge, checking both Disassembly and Preparation Wait until the cylinder heads cool before removing them' from the en gine block. After removing the cyl inder heads, thoroughly clean 'the mating surfaces oft the head and block. Use a standard putty knife to scrape cerefully all gasket material, dirt, carbon deposits and rust from these surfaces. (Fig. I) A chemical cleaner should be used on aluminum surfaces. ~ lengthwise and crosswise. (Fig. 2) If distortion is greater than .006 over all or more than .002 per six inches of machine surface, then the surfaces must be refinished. \ \ 61 CAUTION: If mating surfaces are ground or milled it may be necessary to check and take action in several areas: (1) Shorten the length of the bolts to prevent torque loss due to bottoming. (2) Rechamfer the top of the bolt holes, this prevents the threads from pulling above the ma chined surface when the bolts are tightened. (3) If more than .010' of stock is removed from the overhead valve V8 cylinder heads, a compen sating amount must be removed from the manifold faces of the cylinder heads to avoid misalignment of the castings upon assembly. (See Fig. 3) In addition, on those engines where the intake manifold fits against the cylinder block, the center section of the manifold will strike the block first making it impossible to obtain a proper fit between the heads and manifold. To correct this requires removal of stock from the cylinder block as shown in Fig. 3. Thoroughly clean cylinder head studs or bolts with a wire brush and treat with a light coat of corrosiveresistant lubricant. Clean the mating surfaces previously scraped with a brush making sure to remove thor oughly all small particles. (Fig. 4) Chase all threads with a sharp tap then blow these holes free of small particles. Check surface of gasket for stamped instructions, such as "top," "bottom," "front," etc. (Fig. 5) To assure the job is done right, al ways check the gasket against its mating surface for correct fit. 62 All Victor head gaskets are manu factured specifically not to require additional commercial sealers for proper installation. Many mechanics, however, prefer to use a good, non hardening sealer on metal gaskets. Where a sealer is used, it should be applied evenly to the metal surfaces only. (Fig. 6) CAUTION: Sealers should not come in contact with rub ber inserts or moving parts. Under no circumstances should a sealer be used on premium Victocor gaskets. Agents used in sealers may create adverse reactions when in contact with metal core materials having a non-metallic surface, hereafter re ferred to as composition materials. All cylinder head bolts should be checked for correct length since the bolts are not necessarily all the same length. With the cylinder head gasket properly positioned and the cylinder head installed, tighten all head bolts to-1/3 of final full torque. In addi tion to recommended torque specifi cations, many refer to maximum permissible torque for each bolt size as it appears in the accompanying chart. (Fig. 7) Bolts should be tightened in the sequence recom mended by the manufacturer. In the absence of manufacturer's recom mendations, the sequence shown in (Fig. 8) should be followed. After the initial tightening, all cylinder head bolts should be re-tightened in the prescribed order to full torque, fol lowing manufacturer's specifications. Other Gaskets Automotive gaskets have a wide variety of uses besides sealing cyl inder heads. For the most part, all mating components on today's auto motive engines are joined by a gasket to form an effective seal. However, conditions under which good perfor mance must be maintained can vary. Consequently, as these conditions change, the type of gasket that may be required also can change from one application to another. Intake Manifold Gaskets Many applications can be sealed with less exotic "paper" materials. A va riety of sheet materials are available in this area, ranging from an oil and water resilient paper for such appli cations as timing cover, water pump, oil pan, thermostat gaskets to that of a compressed asbestos sheet pack ing made from asbestos fibers and rubber binders. This rubber/asbestos material is used as intake manifold gaskets, oil pump gaskets, fuel pump gaskets, various housing gaskets, and numerous other applications. Some tips to help you make more effective intake manifold gasket in stallations are: Inspect the intake manifold for cracks, warpage or improper machining that will prevent an accurate fit. Clean all mating surfaces and make sure there are no scratches that will prevent a gasket seal. Secure gaskets to the head and block using a quick drying adhe sive to prevent the end-strips from popping out or the gaskets from slipping. Put a dab of non hardening sealer at the gasket corner joints. Also apply a non hardening sealer to the intake manifold gaskets around the in-. take ports and the water open ings. NOTE: Do not use sealers on composition materials. Position the manifold on the engine, making sure not to slide it on the gaskets as this may tear or misalign the gaskets, thereby preventing an effective seal. Install all bolts finger tight. Fol lowing the manufacturer's recom mended sequence, tighten to the proper torque. If this infoimation is not available, torque the bolts to 15 PSI in a criss-cross pattern starting from the center bolt then working out. Repeat this procedure tightening to full factory torque. Retorque to manufacturer's spec ifications after engine reaches normal operating temperature. Valve Cover Gaskets Composition cork is perhaps the old est and one of the most reliable gas ket materials available. It is generally used on oil pan and valve cover appli cations; when properly installed while new, cork materials perform very well in these applications. However, be cause of a natural tendency to shrink in storage, most cork materials used today are neoprene or aluminum coated. Many mechanics prefer a material that will not shrink or dis tort and, therefore, use a cork/nlbber product. Victor Cork/Rubber material as the name implies, consists of cork particles held together by synthetic elastomer (rubber) binders. Victor 63 S.A.E. GRADE AND BOLT CHART FIGURE 7 1 or 2 5 S.A.E. oGRADE 0 6 0 8 0 RECOMMENDED FOR COMPETITION AND CRITICAL USE 0 1/4 DIA. 5/16 " 3/8 " 7/16 " 1/2 " 9/16 5/8 " 3/4 " 7/8 " 1" 5 Ft. lbs. 9" 15 ' 24 " 37 " 53 74 ' 120 " 190 " 282 " 7 Ft. lbs. 14 " 25 *' 40 " 60 " 88 120 " 220 " 302 " 466 " 10 Ft. lbs. 19 " 34 " 55 " 85 " 120 167 " 280 " 440 " 660 " 10.5 Ft. lbs. 22 " 37 " 60 ' 92 " 132 180 " 286 " 473 " 714 " 11 Ft. lbs. 24 " 40 " 65 " 97 " 141 192 " 316 " 503 " 771 " cork/rubber is the preferred material because it possesses the compressive characteristics of cork and the di mensional stability of rubber. These gaskets wjll not shrink, crack or be come brittle in storage. Cork/rubber gaskets will seal tight without spread ing, and need not be glued to the cover to prevent gasket slippage. Victor cork/rubber gaskets are dur able, impervious to liquids and with stand the high heat ranges found in today's engines. This material is most suitable for valve cover, push rod cover and oil pan applications. Vidor Rubber gaskets also may be used on valve cover, push rod cover and oil pan applications. Because of the characteristics of rubber, however, additional care should be exercised during installation. Since rubber will not envelop or absorb foreign parti cles, mating surfaces must be thor oughly cleaned and trued before installation. In addition, most rubber gaskets must be positioned on the application by the use of small, quarter-inch droplets of common trim cement spaced at two-inch intervals on the gasket. Installation procedures for valve cover and push rod cover gaskets are as follows: 64 Clean all surfaces on cover and block. Check cover for dents or un evenness by placing it on the head without a gasket and check ing for rocking action. Straight en any irregularities with a hammer while the flange is se cured to a flat narrow bar stock. Check the fit and alignment of the gasket; when using a rubber gasket, it is necessary to glue the gasket to prevent slippage. Uniformly, tighten the bolts to the manufacturer's recommended specifications to insure proper seating and sealing of the gasket. A simple rule of thumb is that a gasket expected to function under extreme heat and pressure is generally metal or a metal core-supported com position sheet; a gasket sealing a standing fluid under controlled load ing is usually a treated sheet stock; and a gasket expected to seal a splash ing fluid under lightly loaded condi tions is usually cork/rubber, cork or rubber. Good gasket design requires exten sive research and development engi neering. However, even the finest gasket design will perform only as well as it is installed. By following these procedures and paying strict attention to manufac turers' specifications, you can perform long lasting and trouble-free sealing jobs. BULLETIN NO. PCE-017 DATE 8/81 HEAD GASKETS SUBJECT: VICTOR CYLINDER HEAD GASKET- SILICONE-TEFLON* ANTISTICK RELEASE COATING Release agents are optional and are not specified by the O.E.M. on all head gaskets for cast iron head and block engines. However, an antistick coating is required on head gaskets for aluminum head or block engines so that the flanges will release clean to eliminate gasket removal problems and avoid scratching the aluminum sealing surface. In the future, all Victorcor head gaskets will have an "invisible to the eye" antistick coating which derives its excellent release properties from its silicone and teflon content. This Silicone-Teflon* coating is not the same as the relatively thick red Teflon coating applied to our Solicor head gaskets for the late model Oldsmobile engines. 'Teflon is a registered Dupont trade name for Polytetroflouroethylene (PTFE). // / 79 BULLETIN NO. PCE-018 DATE 8/81 WATER PUMP MOUNTING GASKET FORD 400 CID ENGINE WATER PUMP MOUNTING GASKET ON 228-1648 Somewhere during the production period of 1975 to 1977 Ford experienced problems with the "York" style air compressor, and for this short period installed the GM style compressor. The GM compressor is longer than the standard York style and this required the water pump to be spaced out an additional one inch. A cast iron spacer was used, thus creating the need for an additional mounting gasket between the engine and the cast iron spacer. We do not package 2 mounting gaskets for this application as Ford only used the GM style compressor for a short period of time. When this additional gasket is needed, one can use a Victor water pump mounting gasket part number (K27158) 5 81 -AutoCare BULLETIN NO. PCE-019 DATE 10/81 4.2L/5.0L ENGINES OIL LEAKS FORD LINCOLN-MERCURY 1980-81 4.2L/5 .OL ENGINES OIL LEAKS 1980-81 cars and light trucks with the 4.2 liter or 5.0 liter engines may have seepage or leaks at the oil pan bolts. These bolt holes are threaded through the crankcase. To prevent the seepage/leakage problem, apply a small amount of Victor Odd Job to the oil pan bolts before installation. Be sure the oil pan is not damaged and the mating surfaces are very clean. Of course, our cork/rubber oil pan gasket, #0530531 is recommended. CAUTION: Do not apply Odd Job on any bolt that is not drilled all the way through. V/ 83 BULLETIN NO. PCE-020 DATE 10/81 CHRYSLER 225 SLANT SIX-SPARK KNOCK > j CHRYSLER 225 SLANT SIX-SPARK KNOCK ' Chrysler Corporation advises that some 1978-80 vehicles with the 225 slant six ; have spark knock problems. i Originally, these engines had beaded steel head gaskets .015" thick. Replacing j the steel gasket with our Victocor gasket, # 1162-VC can help. Our Victocor gasket : is .045" thick .036" compressed so it will lower the compression ratio slightly, | eliminating most cases of spark knock. Of course, the mechanic should check : timing and carburetor adjustment to be sure they are within specifications. i I ! I f BULLETIN NO. PCE-021 DATE 10/81 GM 350 DIESEL CYLINDER HEAD GASKET GM 350 DIESEL CYLINDER HEAD GASKET The Victor Solicor Diesel Head Gasket, #3685, designed for tTT GM 350 diesel engine is the most advanced designed head gasket for the replacement market. The Solicor gasket has the same no-retorque characteristics of the famous Victocor line of gasket with a silicone-teflon* anti-stick coating for ease of removal. Plus the Solicor gasket design has the Victocote area coating around water passages for improved sealing. When installing the Victor Solicor gasket, care must be taken to assure the prechamber flange face the cylinder head. You will notice beneath the prechamber flange there are slots cut into the facing material. These are relief slots which allow any coolant leaks around the prechamber to drain overboard instead of into the combustion chamber. 'Teflon is a registered Trademark of the DuPont Corp. 87 -AutoCare BULLETIN NO. PCE-025 DATE 11/82 VICTOR GASKET OFFERS EASY METHOD FOR CHECKING MATING SURFACE FLATNESS VICTOR GASKET OFFERS EASY METHOD FOR CHECKING MATING SURFACE FLATNESS TOLEDO, OHIO -- Automotive aftermarket engineers at Victor gasket suggest an easy and accurate way to check the flatness of mating surfaces sealed by gaskets. This tecboique is particularly useful for checking the flatness of cylinder heads and engine blocks where sealing is critical. The key is to use pressure-sensitive NCR-type paper, which is available where you buy office supplies. Using a gasket as a template, cut the paper into the shape of the gasket. While holes for attaching bolts must all be cut, other openings, such as coolant, oil, and exhaust passages and cylinder bores need not be cut. Install the double thickness NCR paper and torque attaching bolts to specification. When you disassemble the pieces, the light impressions on the paper will represent low spots and the dark areas high spots. The components can then be resurfaced as necessary to assure positive sealing. This technique is particularly helpful for situations in which an engine compartment layout makes it awkward to use a straight edge and feeler gauge to measure flatness. While Victocor permanent-torque head gaskets offer the best sealing and conformability possible, no gasket can seal effectively where mating surfaces are not reasonably flat. / 99 BULLETIN NO. PCE-027 DATE 11/83 AUDI/VOLKSWAGEN DIESEL CYLINDER HEAD GASKET INSTALLATION AUDI/VOLKSWAGEN DIESEL CYLINDER HEAD GASKET INSTALLATION Head gaskets ol differing thicknesses are required for the Volkswagen and Audi diesel engines. A replacement gasket must be of the same thickness as the one removed and is identified by grooves in the edge of the gasket. In the event that the old gasket has been discarded, the proper gasket thickness can be determined by measuring piston protrusion. With the piston at top dead center, measure the piston height above the block to determine piston protrusion and then use the following formula: 1976-80 Volkswagen 4 Cyl. 1.5L Diesel .017" - .025" (0.43mm - 0.63mm) Use 2 Groove Victor 3666 .026" - .032" (0.64mm - 0.82mm) Use 3 Groove Victor 3664 .033" - .036" (0.83mm - 0.92mm) Use 4 Groove Victor 3669 .037" - .040" (0.93mm - 1,02mm) Use 5 Groove Victor 3665 1981-83 Volkswagen 4 Cyl. 1.6L Diesel .026" - .032" (0.67mm - 0.82mm) Use 1 Groove Victor 3728 .033" - .036" (0.83mm - 0.92mm) Use 2 Groove Victor 3729 .037" - .040" (0.93mm - 1.02mm) Use 3 Groove Victor 3730 1980-82 Audi 5 Cyl. 2.0L Diesel .026" - .031" (0.67mm - 0.80mm) Use 1 Groove Victor 3692 .032" - .035" (0.81mm - 0.90mm) Use 2 Groove Victor 3692W .036" - .040" (0.91mm - 1.02mm) Use 3 Groove Victor 3692X Always install gasket with the word "Open" or "Top" facing up. ! \\ V.. This information is provided from best available sources. NAPA Engine Parts cannot assume responsibility for accuracy of data or consequences of its application. 103 BULLETIN NO. PCE-028 DATE 11/83 REVISED REAR MAIN SEAL INSTALLATION PROCEDURE FOR 1982-83 GENERAL MOTORS 4.3L & 5.7L DIESEL ENGINES REVISED REAR MAIN SEAL INSTALLATION PROCEDURE FOR 1982-83 GENERAL MOTORS 4.3L & 5.7L DIESEL ENGINES Note: General Motors has revised its rear main seal installation procedure for the engines mentioned above. The procedure is as follows: 1. Clean the seal groove in the block and/or cap as necessary. 2. Apply a thin even coal (about two drops of bonding adhesive) of GM pari # 1052621, Loctite 414, Fel- Pro 361 (Mighty Seal), or equivalent over the entire seal surface of the groove. 3. WITHIN ONE (1) MINUTE, install the seal. After one minute, the adhesive begins to cure and loses its bonding ability. Most adhesives have a shelf life of about one year, but should be considered usable if it flows freely from the container. The above procedure should also be used on all previous Oldsmobile manufactured diesel engines which utilize a rope-type rear main seal. This information is provided from best available sources. NAPA Engine Parts cannot assume responsibility for accuracy of data or consequences of its \ application. 105 mm -AutoCare- BULLETIN NO. PCE-029 DATE 11/83 VALVE COVER REMOVAL ON GM 4.3L & 5.7L DIESEL ENGINES VALVE COVER REMOVAL ON GM 4.3L & 5.7L DIESEL ENGINES Easier removal and fewer dents in valve covers may be achieved when using the following advice offered by GM regarding their 4.3L (260 CID) and 5.71 (350 CID) diesel engines. According to GM, production lines are currently using a black RTV sealer lot valve coverto cylinder head sealing which has greatly improved adhesion characteristics. This particular sealer is used because 4.3L and 5.7L diesel engine valve covers are being manufactured with spacers to hold them away from the cylinder head. The space allows the valve cover to expand and contract during heating and cooling cycles, thus requiring a sealing bead that won'd break during these cycles. To obtain the space, the V-8 covers use "coined in place" spacers and the V-6 covers use separate snap in place clips. Removal may be eased by the use of a tool such as the Burroughs BT8315 or equivalent. (See. Fig. 1) To use the tool, remove the valve cover bolts and position the tool on the inboard (inside) edge of the cover, midway between cover ends. Engage re mover tool tabs (#1) under the valve cover flange and tighten the forcing screw (#2) against the intake manifold. As the forcing screw is tightened, watch the valve cover flange. If the flange begins to bow, stop. Fig. 1 Leave the tool in place and wrap a cloth around a short board. Place the cloth wrapped board parallel to and against the side of the valve cover above tool. Strike the board with a mallot. The board and the cloth will absorb the blow of the mallot without denting the valve cover while loosening the RTV bead and allowing valve cover removal. When servicing engines built without valve cover spacers, use separate snap in place clips. These are available in quantities of 25 per package under GM part number 22521731. i This information is provided from best available sources. NAPA Engine Parts i \. cannot assume responsibility tor accuracy of data or consequences of Its application. 107 BULLETIN NO. PCE-047 GASKET TECHNOLOGY DEMANDS ATTENTION TO DETAIL Most countries have banned asbestos from gaskets, so the automotive industry is now using a number of substitutes. Some gaskets are now made from layers of expanded graphite bonded to a perforated steel core. Others are made of composite materials clinched to a perforated steel core and coated with an anti-stick material such as Teflon. The Victor 2000 gasket, for example, has a perforated core with a Teflon coating. (Figure 1) Other applications require the addition of elastomeric beads to form a seal. The gasket needs to move a little, as the head expands and contracts, to provide a good seal. A Teflon coating allows for this movement. Sealant will only prevent this necessary movement. Surface finish is also important. If the surface is too rough, the expansionjind contraction of the head will rip up the gasket; a surface that's too smooth may allow too much gasket motion and actually push the gasket out the side. A 54 Ra finish is normally recom mended for aluminum heads. Some hard and soft gasket designs also have elasto meric beads printed onto key parts of the gasket. The raised area creates additional load in critical areas and helps seal problem areas. Cost of Change Figure 1 Victor 2000 Head Gasket Laminated steel gaskets are becoming common on Japanese imports, and they are also under consider ation for some new domestic engines like the Ford 4.6L V8. When working with steel gaskets, remember that these gaskets require a near-perfect surface finish-- approximately 27 Ra--or the gasket won't seal. Changes in gasket materials mean improved sealing capabilities, but it also means higher costs. Many pan gaskets, valve cover gaskets, and-others now use heat-resistant synthetic rubber instead of cork. Rear main seals and valve stem seals are often made of expensive materials such as Viton. Other gaskets use a metal or composite carrier with molded rubber. The hard carrier provides a load stop, while the rubber does the actual sealing. Many bimetal engines are using graphite or Teflon to hold a seal as the aluminum head heats up and cools at a different rate than the cast iron block. Typically, these gaskets are designed to be installed dry, without gasket dressing. Service Tip: On engines with low-mileage, the sealing surfaces and rubber beads may appear to be in good condition. However, the rubber often absorbs the fluids and cannot be reused regardless of the gasket appearance. Service Tip: Both the head and the block expand and contract at different rates if they are different metals. Putting a gasket dressing on this type of head gasket can cause sealing problems. V Application Ideas In addition to graphite and Teflon coated gaskets, NAPA Gaskets also offers a multipiece cork-rubber gasket for 4.3, 5.0, and 5.7 liter Chevys. It consists of Tuff-Cork side rails and silicone rubber end seals to replace the OE one-piece molded rubber gasket. (Figure 2) ... 143 f Figure 2 NAPA Multipiece Pan Gasket The Tuff-Cork rails consist of a steel shim between layers of cork. This provides an excellent seal for less cost than the rubber, and the gasket cannot be overtorqued. The Buick 3300 and 3800 intake manifold gasket uses a molded plastic carrier with silicone rubber beads. This gasket has been redesigned for the aftermarket. (Figure 3) The new design uses multilayer graphite with two perforated steel cores and Teflon coating for the 3300/3800 engine. This was done to eliminate cracking at the last port which may occur on the OE design. Figure 3 Redesigned Buick Manifold Gasket <NAPA> Engine Parts FORM NO. A-6691 TT-2850 The following technical information supplied by AMERICAN BRA KEBLOK. CLEANING SLIDING SURFACES - FORD 'L' BRAKE The Ford 'L' type disc brake slides on machined surfaces compared to the earlier floating calipers which moved on pins. Because of this, it is important that the two surfaces on the anchor plate and mat ing surfaces on the caliper be thoroughly cleaned at time of reline. (Fig. 1 & 2) Occasionally, these surfaces have enough rust and corrosion buildup to prevent the caliper from slid ing freely. A sticking caliper will cause poor braking and excessively rapid wear on the inboard shoe. After removing the caliper, vigorously wire brush both ends of the anchor plate and the corresponding mating surfaces on the caliper. All loose rust and corrosion must be removed. Occasionally using a flat file on the caliper surfaces will help if the corrosion is very heavy. Be careful not to remove metal as the slides must remain flat and true. It is not necessary to have bright or shiny metal showing. Also check the caliper slide area for nicks or burrs. These must be removed with a flat file, otherwise the caliper will not slide freely. CAUTION: Do not lubricate slide. Lubricants will only collect dirt and make situation worse. FIG. 1 FIG. 2 When caliper is reassembled a new caliper support spring (Fig. 3) should be used. Be careful when in stalling key that you do not nick or cause a burr on the caliper. This is very easy to do if the keys do not go in squarely. If a burr is started, remove the caliper and file down any burrs. Be sure the key re taining screw is lined up properly with the key and correctly tightened. FIG. 3 R. E. Nelson Manager -- Technical Service 2 TT-3500 The following technical information supplied by AMERICAN BRA KEBLOK. Shoe Anti-Rattle Clip -- Ford `L' Brake The Ford `L' type disc brake uses two different type shoe clips to prevent rattling or clicking when changing from forward to reverse stops. The clips take up the variable space between the ends of the inboard shoe and the anchor plate. Excess clearance at this point allows the shoe to shift from one end of the slot to the other when going from forward to reverse stops or vice versa. This results in an audible clicking sound and is a frequent cause for customer complaints. --* The original type clip (Fig. 1) is available in two sizes. When the clearance between the end of the inboard shoe and anchor plate is up to .030, use the metallic finished clip. When the clearance is over .030, use the blue clip. This clip is installed in the opening at the end of the anchor plate and not on the inboard shoe. The later design clip (Fig. 2) is a universal size and clips on to the end of the inboard shoe. Only one clip size is required as it covers the complete clearance between the anchor plate and inboard shoe. R.E. Nelson Manager -- Technical Service 1 {METALLIC) FIGURE 1 (BLUE) 3 TROUBLE SHOOTING- DRUM BRAKES NN-2-10-79 COMPLAINT LOW PEDAL LOW PEDAL WHICH PUMPS UP SPONGY PEDAL FADING PEDAL HIGH PEDAL HARD PEDAL POSSIBLE CAUSE REPAIR PROCEDURE Low fluid level in master cylinder. Air in hydraulic system. . Leaking wheel or master cylinder. Improper lining adjustment or worn linings. Excessive master cylinder pushrod endplay. Failure in one section of a tandem master cylinder. Low quality brake fluid which.fails un der extreme heat. Aged and weakened hoses which ex pand under line pressures. Brake power booster faulty. Fill and bleed master cylinder. Bleed system completely. Repair or replace cylinder. Check adjusting screw for freeness and readjust linings. Adjust pushrod to required specifica tions. Repair or Replace cylinder. Flush system completely with fresh brake fluid. Replace hoses. Repair or replace unit. Lining worn and/or not properly ad justed. Defective check valves in master cyl inder (no residual line pressure). Replace linings and/or readjust brakes. Rebuild or replace master cylinder. Air in hydraulic system. Low quality fluid which vaporizes un der extreme heat. Worn or cracked drums which flex un der pressure. Improperly ground linings which stretch to conform to the drum. Brake pedal pivot bushing worn or damaged. Bleed system completely. Flush system completely with brake fluid. Replace drums as required. fresh Grind new linings to obtain proper lining surface to drum contact. Replace bushing. Internal master cylinder leak (no ex terior fluid loss visible). Leaking wheel cylinders (leak may be slight and not readily visible). Rebuild or replace master cylinder. Rebuild or replace wheel cylinders. Improper master cylinder pushrod ad justment. Overadjusted brakes (little or no lining to drum clearance). Adjust pushrod to recommended freeplay. Check adjusting screws for correct in . stallation on right or left side of vehicle and readjust brakes to recommended specifications. Glazed or contaminated linings. Kinked lines or restricted hoses in the hydraulic system. Contaminated rubber parts in wheel cylinders or master cylinder. Faulty brake power booster or booster check valve. Brake pedal linkage binding or frozen. Collapsed or leaking intake manifold to power booster vacuum hose. Plugged power booster vacuum fittings. Replace linings and check drums for heat damage. Replace lines or hose as required. Flush hydraulic system completely be fore installation of rebuilt or new cyl inder assemblies. Replace booster or valve. Free linkage and lubricate. Replace hoses and/or fittings. Clean or replace fittings. c 3 7 TROUBLE SHOOTING DRUM BRAKES (CON'T) COMPLAINT PULSATING PEDAL DRAGGING OR PULLING BRAKES NOISY BRAKES POSSIBLE CAUSE REPAIR PROCEDURE Drums out of round (usually caused by hard braking). Incorrect tire pressure or mismatched tires. Contaminated linings. Incorrect wheel or parking brake ad justment. Weak return or hold down springs. Brake pedal linkage not releasing cor rectly. Worn front end parts and shock ab sorbers. Front wheel bearing loose. Master cylinder ports restricted. Contaminated rubber parts which fail to release properly. Drums out of round. Thick or gummy brake fluid which doesn't flow easily. Grooved shoe pads on backing plate which restricts brake shoe movement. Incorrect master cylinder pushrod adjustment. A. "Clicking" Cracked drum tool marks in drum. B. "Chirping" Out of round drum. Weak or broken re turn and/or hold down springs. C. "Squealing" Glazed linings. Contaminated linings. Weak or broken hold down springs. Dust in drums. Bent backing plate. Distorted shoes. Mismatched linings on an axle. Turn or replace drums, check other parts in the drum assembly for effects of heat damage. . Check inflation and/or tire sizes. Repalce linings and check cause of contamination. Adjust as required. Replace all springs and check drum assemETy for effects of heat damage. Check linkage and lubricate. Replace as required. Lubricate and torque to recommended specification. . Clear ports or replace master cylinder. Flush hydraulic system completely before installation of new or rebuilt cyl inders. Turn or replace drum. Flush hydraulic system and rebuild or replace all cylinders. Flatten pads or replace backing plate and lubricate contact points before in stallation of shoes. Adjust pushrod to allow 1/16" to 1 /4" freeplay in brake pedal. Replace drum. Turn or replace drum. Turn or replace drum. Replace springs as required Replace linings and lubricate all shoe contact pads. Check other parts in drum for effects of heat damage. Replace linings. Replace springs. Blow out drums and check linings for glazed surface, also check drums for polished contact surface, and turn. Replace. Replace. Replace linings in sets. TROUBLE SHOOTING-DISC BRAKES NN-2-11-79 COMPLAINT POSSIBLE CAUSE REPAIR PROCEDURE LOW PEDAL WITH BRAKES LOW PEDAL -- NO BRAKES HARD PEDAL FRONT BRAKES HEAT UP AND WILL NOT RELEASE WHILE DRIVING. BRAKES DRAG OR PULL UNEVENLY Rear Brakes not adjusted properly. Warped or tapered disc pads. Leaking caliper piston seal. Low quality, or water contaminated fluid which boils at high operating tem peratures. Air in hydraulic system, or low fluid level in the master cylinder reservoir. Improper wheel bearing adjustment. Excess master cylinder pushrod clear ance. Air in hydraulic system due to improp er bleeding procedure. Leak in lines, cylinders, calipers, etc. Pistons pushed back into caliper bore. Internal leak in master cylinder (no visible fluid loss). Rear brakes not adjusted properly. Bleeder screw open. Pistons frozen in caliper bore. Linings glazed or contaminated. Faulty brake power booster or booster check valve. Power booster vacuum lines or fittings restricted. Residual check valve in line to front disc brakes. Brake pedal does not return fully. Master cylinder pushrod clearance in sufficient. Driver resting left foot on brake pedal. Pistons sticking in caliper bore. Kinked line or restricted hose in brake system. Frozen or incorrect parking brake ad justment. ' Mismatched tire sizes and/or tire pres sures on one or both axles. Contaminated rubber parts which are swollen in cylinder bores. Check adjusting screws and readjust rear brakes.. Replace pads in axle sets and check caliper for freeness on guide bolts. Rebuild or replace caliper. Flush system completely with fresh disc broke fluid. Fill master cylinder reservoir and/or bleed hydraulic system. Adjust wheel bearing to proper torque setting. Adjust master cylinder pushrod to spe cified freeplay. Bleed hydraulic system in correct se quence. Repair as required and bleed hydraulic system. Apply brake pedal two or three times to seat pistons. Rebuild or replace master cylinder. Adjust rear brakes. Close bleeder screw and bleed hydrau lic system. Rebuild or replace caliper assemblies. Replace linings. Replace booster and/or check valve as required. Clean and/or replace lines and fittings as required. Remove residual check valve from master cylinder outlet leading to front wheels. Free up linkage and lubricate. Adjust master cylinder pushrod to ob tain proper clearance. Instruct driver about brake pedal sen sitivity in disc brake equipped cars. Repair or replace as required. Replace as required. Free brake cable and/or adjust as re quired. Check and correct. Flush system completely and replace all rubber parts. 9 TROUBLE SHOOTING DISC BRAKES (CON'T) COMPLAINT BRAKE PEDAL PULSATION NOISE DURING APPLICATION POSSIBLE CAUSE REPAIR PROCEDURE Loose or worn front wheel bearings. Faulty metering or proportioning valve. Pistons sticking in wheel cylinder or caliper bores. Contaminated linings or pads. Excessive lateral runout and/or lack of parallelism in front rotors. Wheel bolts improperly torqued caus ing a warped rotor or drum. Rear drums out of round. Loose or worn front wheel bearings. Caliper guide bolts worn or loose. Pads or linings worn excessively. Scored rotors. Disc pads contaminated with fluid. Groaning sound under light applications. Anti-rattle clips missing or not posi tioned on disc pads. Disc Pad-to-caliper clearance excessive. Rotor rubbing on caliper housing. Caliper mounting bolts too long. Replace and torque to specifications. Replace as required. Check and replace parts as required. Determine source of leak and replace or rebuild parts as required, replace pads. Check for runout and/or lack of parallelism and turn rotors or replace Retorque bolts to proper specifications and check rotor or drums for runout. Turn or replace drums. Replace and/or readjust wheel bear ings to specified torque. Replace bolts and torque to specified settings. Replace in axle sets. Check pads and resurface or replace rotors. Rebuild calipers and replace pads. This is normal, can be eliminated by increasing braking pressure slightly. Replace anti-rattle clips or correct po sitioning of clips. Remove excess pad to caliper clearance by crimping locating clips on pad backs. Check for build-up of road dirt or mud, etc. on caliper check caliper tightness to adapter plate. Install bolts of correct length and ten sile strength. 10 HNflPflb AutoCare FORD SLIDING CALIPER SERVICE TIPS Ford has issued a bulletin recommending that when servicing the Sliding Caliper, that the machined surfaces on the Anchor Plate and Caliper be wire brushed, to remove any rust or other corrosion. When re-assembling the Caliper Assembly onto the Anchor Plate, lubricate the surfaces indicated in the illustration, with a high temperature grease and remove any excess lubricant to prevent contamination of the disc pads. NN-2-13-79 Also recommended, is checking the dust shields to determine if they are adjusted correctly. They can be adjusted by bending, as shown in the illustration, to a dimension of 5/8". This is measured from the dust shield to the rotor face. Incorrect adjustment may result in a difference in cooling and brake response between the two disc brake assemblies. . 11 BULLETIN NO. S-73-9U TO ALL UNITED SALES REPRESENTATIVES SUBJECT: BRAKE LOCK TROUBLE SHOOTING GUIDE The following outline lists operating problems which could possibly be eneeuntered and test procedures to be used to determine which part of the system is possibly malfunctioning. Brake Lock Will Not Hold -- 6-6601 1. Check "Hot" lead from power source at dash control switch with test lamp. If test lamp does not light, check/ replace lead. If test lamp lights, switch on dash control switch and check switch terminal that leads to brake lock. If test lamp does not light, replace dash control switch. If test lamp does light, move to brake lock and check incoming lead from dash control switch. If test lamp does not light, check/replace lead from dash control switch. If test lamp does light, check for poor ground. If ground is good, brake lock is faulty or sticking. 2. To check brake lock, leave dash control switch in "On" position and place jumper wire across the two terminals momentarily. A "clicking" sound should be heard. If this "clicking" cannot be heard, brake lock solenoid is either defective or valve is jammed. To check valve and seals, remove brake Jock from vehicle and mount in vise. Hold brake lock at large gold hex portion with wrench and remove 1" plug stamped "out let." Remove and check valve assembly for swollen rubber parts. If all rubber parts appear to be good and valve moves freely in brake lock, the solenoid is bad and brake lock should be replaced. If rubber parts are swollen, the entire brake system should be checked for contamination and flushed before rebuilding and re installing brake lock. Brake Lock Will Not Release -- 6-6601 1. Check dash control switch to see if it is in the "Off" position. Next, disconnect lead from power source and reapply brake pedal. If brakes release, dash control switch is shorted internally and should be replaced. 2. Check and make sure brake lock has not been installed between master cylinder and a remote brake booster. 3. Disconnect line at inlet side of brake lock. If brakes release, problem is not in the brake lock. Check vehicle for brake system malfunctions. If brakes do not release, disconnect line at the outlet side of the brake lock. If brakes release, brake lock is faulty and should be replaced. 4. If brake lock is faulty, check as outlined in preceding section. General -- 6-6601 & 6-6602 1. If the brake lock seems to release by itself after a short time, check entire brake system for leaks as this will cause a like condition. 2. Install brake lock to actuate all four wheels only on trucks equipped with a vacuum booster. 3. The 6-6602 lever lock is a manually actuated control valve and should be replaced if the action of the lever lock seems erratic. If the valve sticks in the on position and the brakes will not release, test as with the 6-6601 brake lock to determine if lever lock is at fault. (See Section 3, Under Brakes Will Not Release.) 13 BULLETIN NO. ST-74-1 U POWER BRAKE CHECK VALVE The power brake check valve is designed to maintain vacuum in the power booster by preventing air from entering the booster through the intake manifold connecting hoses when the engine is off. The diaphragm in this valve is held closed by the vacuum in theT>ooster (see illustration). If the diaphragm leaks, a loss of vacuum will occur, and greater pedal pressure will be required to stop the vehicle. Check valve failure can be caused by either deterioration due to age, high engine compartment temperatures, or by the engine "backfiring" through the carburetor, which pressurizes the upper portion of the check valve and can cause damage to the diaphragm or valve body cover. Damage by engine "backfire" is more prevalent in the winter months and complaints of hard feeling brake pedals may indicate possible damage in the check valve assembly as well as deterior ated diaphragms, which lose their resiliency in cold weather and won't seal properly. Leaking check valves can be identified by this simple test: Run engine to medium speed. Re lease accelerator and turn off engine. This builds up vacuum. Wait 90 seconds and apply brakes. Two or more applications should be power assisted. If applications are not power assisted. . . . disconnect vacuum hose from intake manifold or power brake check valve. Blow into hose attached to check valve, if air passes through it, the check valve is bad and should be replaced. The United No. 89000 Check Valve replaces most popular O. E. check valves (check application) and the aforementioned facts should help increase your sales of this item. 15 BULLETIN NO. ST-75-1 U TROUBLE-SHOOTING POWER BRAKES BASIC TEST 1. With engine off - Depress and release brake pedal several times to remove all vacuum from the power booster. 2. Depress pedal and hold with light pressure (15 to 25 lbs.). -- 3. Start the engine - If the power section is operating, the pedal will fall slightly. IF POWER SECTION IS OPERATING, GO ON TO THE VACUUM LEAK TEST. IF NOT, CONTINUE WITH STEP NO. 4 OF THE BASIC TEST. 4. Disconnect the vacuum hose from the power brake check valve. 5. Start the engine - Check the vacuum with a vacuum gauge. There should be at least 14 inches of vacuum. IF VACUUM SUPPLY IS 14 INCHES OR MORE, POWER SECTION IS DEFECTIVE AND MUST BE REPLACED. IF VACUUM IS LESS THAN 14 INCHES, CONTINUE WITH STEP NO. 6 OF THE BASIC TEST. 6. Replace or repair vacuum hose. Check for and repair all vacuum leaks in the entire system. Also, tune or repair the engine as required to increase the vacuum to 14 inches. 7. When adequate vacuum supply is obtained, repeat the basic test. VACUUM LEAK TEST 1. Run engine to medium speed. Release accelerator and turn engine off. This builds up vacuum. 2. Wait ninety (90) seconds and apply brakes. Two or more applications should be power assisted. IF APPLICATIONS ARE POWER ASSISTED, GO ON TO THE HYDRAULIC LEAK TEST. IF NOT, CONTINUE WITH STEP NO. 3 OF THE VACUUM LEAK TEST. 3. Disconnect the vacuum hose from the intake manifold and blow into the hose.. If air passes through, the power brake check valve is defective and must be replaced. 4. If no air passes through in Step No. 3, the power booster is defective and must be replaced. !< 19 HYDRAULIC LEAK TEST 1. Start the engine - Depress and release brake pedal several times. Then depress and hold pedal with 25 to 35 lbs. pressure. 2. If pedal falls away, the hydraulic system is leaking. A. Check for external leakage at wheel cylinders, calipers, hydraulic lines, hoses and fittings. Repair as required. B. If no external leakage is present, there may be an internal leak in the master cylinder. 20 BULLETIN NO. ST-78-1U LOW BRAKE PEDAL Properly bleeding the brake system will remove air from the brake system, and eliminate a spongy feeling brake pedal. The key here is a low, firm, brake pedal. If the brake system has been properly bled, and the brake pedal still moves too far down, this indicates that the brake shoe to drum clearance is excessive. The hydraulic brake system is a positive displacement system. If the brake pedal moves too far, it is doing so because the master cylinder is forcing an excessive amount of brake fluid into the wheel cylinders to move the brake shoes outward against the brake-drums. Adjusting the brake shoe to drum clearance properly will shorten the distance the shoes have to travel. This will, in turn, shorten the required movement of the brake pedal. Since this problem is usually noticed near the completion of a brake job, the easiest method of solving the problem is to use a brake adjusting tool, adjust the brake up until the wheels cannot be turned, then back off the adjuster screws one full revolution. This will be about eighteen to twenty "clicks" on a self-adjusting brake, and ten to twelve "clicks" on the older manually adjusted brake assemblies. After the excess shoe to drum clearance has been eliminated, the brake pedal should not move more than 1-1/2" to 2" before brake response is noticed. NOTE: Any check for brake pedal response, or height on late model vehicles equipped with power brakes should be done with the engine off, and all vacuum, or hydraulic assist exhausted from the booster. Most power brake equipped vehicles will give a false indication of brake pedal feel with the motor running, so verify brake pedal height with the motor off. When checking a power brake equipped vehicle for the amount of pedal travel before the brakes actually apply, make certain the vehicle is in motion. Of course, this test should be conducted at slower speeds, and in an open area. r, ...CORRECT BRAKE PEDAL HEIGHT 21 Here are some tips to help you install exhaust systems faster and easier. These suggestions have been accumulated from installers throughout the country who have found ways to do their job better. You may find some helpful information to make this profitable service even easier for you to perform. TIPS FOR SAFER AND EASIER INSTALLATIONS On all cars, expecially those equipped with catalytic~converters, make sure the system has cooled down sufficiently before working on it. Lay out all the new parts to be installed, making sure all correct parts are on hand, including any required mufflers, resonators, pipes, clamps, hangers and flanges. On any pipes which are sound and will be reused, remove clamp grooves from pipes with a NAPA Exhaust Systems pipe expander (35258). Also use the pipe rounder (35961) to make sure that the pipe ends are properly rounded to fit well. To insure a gas tight seal, use NAPA Exhaust Systems Muffler/Pipe Sealing Compound (35959) on both the muffler and pipe surfaces when connecting them. The use of the compound will enable you to easily rotate the muffler and pipe for proper alignment. Depending on the type of lift, it may be necessary to raise the body of the car from the frame, taking the weight off the springs to give clearance at the rear axle. NAPA Lifting Equipment offers two versions of special 3/4 Ton Under Hoist Stands, which are ideally suited for this purpose. (Part numbers 91-781 and 91-779). Generous use of penetrating oil on all threaded connections will simplify and hasten removal of the system. SPECIAL HINTS FOR EXHAUST PIPES Because Exhaust Pipes bum off more corrosive acids than the rest of the system, they are not replaced as frequently. However, extra care must be taken when replacing or reusing the exhaust pipe to avoid complications. Remove the battery ground to avoid shorting the electrical system (this is particularly true for 8 cylinder Chrysler products). When removing manifold nuts, a hand-held ratchet wrench will give you a better "feel" lessening the possibility of stud breakage. 27 When removing the exhaust pipe, take extra care to insure that the heat riser valve doesn't fall and get damaged. If the manifold uses bolts to hold the exhaust pipe, replace with new bolts and nuts. If studs are used, chase the threads of the manifold studs and use new brass nuts to connect the exhaust pipe to the manifold. Thoroughly lubricate all threads so nuts go on faster and easier. Clean all gaskets, ball and socket surfaces to insure gas-tight seal. To keep exhaust gaskets in place, slip a rubber band over the manifold studs, freeing both hands to install the exhaust pipe. Heat from the engine will cause the rubber band to disintigrate immediately upon engine start-up. If the exhaust pipe has a welded flange, it can be immediately tightened securly. On exhaust pipes with loose flanges, bolts should only be tightened snugly after the system has been thoroughly inspected for alignment and clearance. FINAL INSPECTION FOR PROFESSIONAL RESULTS ~~ To insure the professional results that both you and your customer expect of you, take a couple of minutes to recheck the entire exhaust system. Is the system in proper alignment? Is there adequate clearance throughout the whole system, or will it ground out from engine torque or bumpy roads? NOTE: If the exhaust system replacement was performed on a frame lift hoist, recheck for clearances when car is on the ground. Are all threaded connections tightened securely? Are hangers supporting the system, not pushing it down? Is the entire exhaust system completely and safely sealed from gas leaks? With the engine running in neutral, check this by holding a shop rag over the outlet of the tailpipe, listening for leaks at all muffler and pipe connections, as well as rattles over the whole system. Exhaust system replacement is not very difficult, but it is extremely impor tant to your customer's well-being. It should be a major contributor to your gross profits, and it gives your customers one more reason to keep coming back to you, their NAPA Gold Hat Pro. -228 r AutoCare REMOVING STUBBORN MANIFOLD CONNECTIONS TT-3400 It's easy - if you know what you're doing! The secret, of course, is to have patience and not carelessly break a stud or cap screw in the first place. A manifold stud or cap screw usually breaks due to excess torque applied in removing a rusted nut. There are several ways of removing stubborn nuts from manifold studs or cap screws from manifolds without breaking otherwise usable studs or screws. The first would be liberal use of penetrating oil directed on the stud nut or manifold where the cap screw goes into the.manifold. You may split the nut by placing a chisel on the end of the nut parallel to and against the stud (see diagram 4 on last page). The chisel is then driven into the nut to split it and facilitate removal of it with a suitable tool. Damaged threads can then be "cleaned up" with a thread chaser. The best way to remove a frozen nut is, of course, heating it to a cherry red color with an oxy acetylene torch and removing it while still hot. This should only be used when suitable conditions exist as outlined later. Normal rust and corrosion often cause manifold nuts and cap screw heads to be somewhat undersized. To prevent rounding off the hex points on nuts or screws, we recommend the use of six point sockets instead of the more nor mal twelve point tools. These tools,allow more contact with the screw or nuts. In many cases, undersized (using 1/2" for 9/16") sockets or metric sockets slightly smaller than nominal American sizes may be useful and save grief. Before you start working, check the following points: 1. Laws may prohibit use of a torch in service shops. If you can use one, use an oxy acetylene torch which produces high heat to con centrated areas. Never use a torch if there is a fuel leak or fuel odor anywhere in the area. Do not use it near fuel lines. Torch heat is just as dangerous as the flame. 2. Unless you're a professional, do not attempt to use an air or electric impact wrench to apply force against a rusted nut. Its power is difficult to control on marginal studs. 3. Remove the battery ground cable to avoid grounding out the elec trical system. This is particularly necessary on Chrylser products. 4. If a stud or capscrew breaks, manifold removal may be necessary for access in some instances. It's harder to break the stud or cap screw on newer car models, simply because they have not deteriorated as much as older models. Ford products are less likely to break than other makes, regardless of age. Most Chrysler products have cap screws and nuts, therefore, if one breaks, it is readily removable. 29 6. Severely eroded, though unbroken studs or cap screws should be replaced, because they can't be relied upon to hold the replacement system. If the stud or cap screw breaks flush with the manifold, try using EZ out screw extractors. If this doesn't work, you'll have to drill the stud or cap screw out. 1. Center punch the stud and lubricate with cutting oil. 2. Begin drilling using a .1/8" drill. Maintain the center direction as you drill straight through to the end of the stud or cap screw. 3. Continue re-drilling, using progressively larger drill sizes until you reach the tap drill hole size. 4. Grind out a 45 angle chisel from a small diameter tapered punch (see diagram 1 on last page), and chip at the remaining thread edge, straight through in one location. The thread-skeleton will fall away. If the hole thread is damaged, you may re-tap or leave as is. The undisturbed 320 or so of the hole is sufficient to hold another stud or cap screw. 5. If too much thread is damaged, you can retap to the next larger stud size or completely drill the manifold with an oversized drill, and use a bolt and nut. However, in most cases, the bolt and nut approach is not recommended,because the shape of the manifold does not always offer a flat surface for the nut to tighten against. If the broken stud or cap screw has a stub left, but without manageable threads, and you can use a torch: 1. Heat the section of the manifold next to the stud or cap screw using an oxy acetylene torch(see diagram 2 on last page). The heat will expand the manifold on two sides of the hole reducing pressure against the stud or cap screw. It will also disturb interfering rust and scale. 2. When the manifold becomes a dull red color, use a suitable tool on the stud or cap screw, and screw it out. Alternately loosen and tighten if removal is still difficult. 3. If it is still stuck, arc weld a nut to the end of the stud or cap screw and turn it out. 4. If not successful with the welded nut, cut the stub flush and drill it out as outlined above. If the broken stud or cap screw has a stub without manageable threads, and you can't use a torch, use a commercial stud remover. If the remover does not work: 1. Lubricate with penetrating oil. (Both ends if set in open hole.) 2- - 30 2. Place a blunt punch at least %" diameter squarely on the end of the stub. Two or three good blows with a hammer will help shock and loosen the threads. An air hammer with a blunt punch will work also. You can also shock the threads loose by hammering the thinnest section of the manifold next to the bolt. Don't hit wildly, as you may fracture the manifold. Use a controlled square blow. 3. Turn the stub out with back and forth turns with a suitable tool. Recondition threads with a tap or thread chaser. If a threaded stub is left: 1. Use a commercial stud remover or "double-nut" if possible. Use penetrating oil and hand wrench it out. A combination of heat and shock techniques may also be used. Do not use oil on red hot surfaces, as the oil may catch fire. If the stud unscrews from the manifold, but the nut is still stuck on it, place the stud over an anvil. Hit the nut with a hammer blow on each flat side, rotating the nut each time. Put the stud in a vise, being careful not to damage the threads, and gently turn the nut off using penetrating oil. You may also split the nut by chiseling the flat surface of the nut(see diagram 3 on last page). Ten minutes of patience and common sense can save hours of needless labor. Broken stud removal need not be an obstacle to efficient exhaust system installation. These removal procedures may also be applied to broken stud or screw removal on other parts of the vehicle as well. We recommend the use of antisieze compound on all threads and the use of brass nuts on studs when reassembling manifold connections. You may be the next person to replace that pipe and would then benefit from this extra step. -3- 31 32 TT-3300 The following technical information supplied by AMERICAN BRAKEBLOK. REAR BRAKE DRUM REMOVAL Vega & Astre 1975-72 Monza, Starfire, Sky Hawk 1975 If the drum cannot be removed because the brakes are adjusted too snugly or a lip has formed on the drum, it will be necessary to release the brake adjuster assembly (Figure 1). Knock out plug in the flange of the brake drum using a chisel or similar tool (Figure 2). Release the rod assembly from the trail ing shoe by pushing in on the rod until it is clear of the shoe (Figure 3). The pull-back spring will then pull the shoes toward each other and the drum may be removed. CAUTION After knocking out the plug in the flange of the drum (Figure 2), be sure to remove the piece of metal from inside the drum area as well as any small pieces of metal that might have fallen from the flange. A new rubber hole cover must be installed when the drum is re installed. If the drum already incorporated a rubber hole cover, remove and replace the old cover. R. E. NELSON Manager-- Technical Service PUSH "IN" TO RELEASE FIGURE 2 37 TT Disc Pad Bulletin No. JO, TR-81-1R DATED APRIL, 1981 TO. ALL NAPA JOBBERS AND MECHANICS PRODUCT: DISC BRAKE SUBJECT: CHRYSLER CORPORATION FRONT END SQUEAL Some Chrysler vehicles may exhibit a front wheel bearing seal squeal. This squeal occurs at speeds over 10 M.P.H. after the vehicle has been driven several miles, with or without the brakes applied. This condition normally causes the people to unjustly condemn the disc pads. Sometimes the disc pads are the problem, but this squeal can be caused by a substitute plastic foam gasket between the splash shield and steering knuckle which is used on some vehicles. SQUEAL results from contact between gasket material and inner wheel bearing seal slinger. This condition DOES NOT INDICATE A DISC PAD MALFUNCTION. This condition may be corrected as follows: Raise vehicle and verify which front bearing seal is causing the squeal by spinning the wheel vigorously. A high pitch, cyclic squeal will be heard if this condition is present. Remove the front wheel, caliper housing, and brake rotor to expose the splash shield and gasket. Trim the gasket so that the circular groove worn in it by the inner bearing seal is completely removed. Reassemble the components and pump the brake pedal several times to take up caliper clearance. PAUL L. LeCOUR Product Manager 43 BULLETIN NO. PCC-012 DATE 11/83 REAR WHEEL ALIGNMENT SHIMS FOR FRONT WHEEL DRIVE VEHICLES.. .COMPLETE ALIGNMENT REAR WHEEL ALIGNMENT SHIMS FOR FRONT WHEEL DRIVE VEHICLES... COMPLETE ALIGNMENT Complete alignment refers to all four wheels being aligned in relation to the geometric centerline of the vehicle. This is important to proper handling and maximum tire life. 1MRUS> *W>ll __ The front wheels steer the vehicle, allowing the rear wheels to direct the vehicle through a turn. When the rear wheels are misaligned, the driver may compensate by turning the steering wheel to an off-center position to maintain a straight ahead direction, sometimes referred to as dog tracking. Ideally, the thrust line should be as close to the geometric center line as possible to minimize the thrust angle. These principles are the same for front wheel drive as well as rear wheel drive vehicles. Dana's exclusive rear wheel alignment shims for front wheel drive vehicles correct rear wheel alignment found in new as well as older vehicles. Three color-coded style tapered shims, offer a full range of correction angles for Chrysler, General Motors and Volkswagen products with front wheel drive. These tough, synthetic shims provide full face contact between spindle and axle, thereby reducing bolt stress versus partial contact shims that are installed on one or two mounting studs. The extremely thin shim profile eliminates the need for chang ing to longer spindle studs and allows a maximum of two shims to be stacked to obtain desired alignment settings. For ease of identification, the approximate degree of correction is embossed on each color-coded shim. The shim charts provided fur ther aid in the selection of the proper alignment shim. This information is provided from best available sources. NAPA Chassis Parts cannot assume responsibility for accuracy of data or consequences of its application. 53 The charts below show camber degrees (+) or (--) with the approximate toe effect for each degree of camber listed in relationship with the outside tire diameter. To order, the corresponding part number or combination of part numbers are listed on the left. RED SHIM APPLICATION: CHRYSLER Le Baron New Yorker (from 19831 DODGE Aries Omni 400 600 Rampage Truck PLYMOUTH Horizon Reliant Scamp Truck VOLKSWAGEN Dasher Jetta Pickup Truck Rabbit Scirocco BLUE SHIM APPLICATION: BUICK Sk y hawk Skylark CADILLAC Cimarron CHEVROLET Cavalier Citation OLDSMOBILE Firenza Omega PONTIAC J2000 Phoenix PART NO. 264 2701 264-2702 264-270.7 264-2704 264-2701 264-2704 264-2702 264-2704 264-2703 264-2704 264-2708 264-2702 264-2708 264-2704 264 2708 Use 121 of 264-2708 CAMBER DEGREE 1/4 1/2 3/4 1 1-1/4 22" 3/32" 3/16" 9/32" 3/8" 15/32" OUTSIDE TIRE DIAMETER 23" 24" 25" 26" TOE CHANGE 3/32" 3/16" 9/32" 3/8" 3/32" 7/32" 5/16" 7/16" 1/8" 7/32" 5/16" 7/16" 1/8" 7/32" 11/32" 7/16" 1/2" 17/32" 17/32" 9/16" 27" 1/8" 7/32" 11/32" 15/32" 9/16" 1-1/2 9/16" 9/16" 5/8" 21/32" 11/16" 23/32" 1-3/4 2 2-1/2 11/16" 25/32" 31/32" 11/16" 25/32" 1" 23/32" 13/16" 1-1/32" 3/4" 7/8" 1-3/32" 25/32" 29/32" 1-1/8" 13/16" 15/16" 1-3/16" 3 1-5/32" 1-7/32" 1-1/4" 1-5/16" 1-3/8" 1-13/32" 4 1-17/32" 1-5/8" 1-1 1/16" ~T3/4" 1-13/16" 1-7/8" PART NO. 264-2713 264-2714 264-2715 264-2716 264-2713 264-2716 264-2714 264-2716 264 2715 264-2716 264-2720 264-2714 264-2720 264-2716 264-2720 Use (21 of 264-2720 CAMBER DEGREE 1/4 1/2 3/4 1 1-1/4 3/32" 3/16" 9/32" 3/8" 15/32" 3/32" 3/16" 9/32" 3/8" 1/2" TOE CHANGE 3/32" 7/32" 5/16" 7/16" 1/8" 7/32" 5/16" 7/16" 17/32" 17/32" 1/8" 7/32" 11/32" 7/16" 9/16" 1/8" 7/32" 11/32" 15/32" 9/16" 1-1/2 9/16" 9/16" 5/8" 21/32" 11/16" 23/32" 1-3/4 2 2-1/2 11/16" 25/32" 31/32" 11/16" 25/32" 1" 23/32" 13/16" 1-1/32" 3/4" 7/8" 1-3/32" 25/32" 29/32" 1-1/8" 13/16" 15/16" 1-3/16" 3 1-5/32" 1-7/32" 1-1/4" 1-5/16" 1-3/8" 1-13/32" 4 1-17/32" 1-5/8" 1-11/16" 1-3/4" 1-13/16" 1-7/8" YELLOW SHIM APPLICATION BUICK Century Riviera 1982 & up 1979 & up CADILLAC Eldorado Seville 1979 & up 1980 &up CHEVROLET Celebrity OLDSMOBILE Cutlass Ciera Toronado 1979 & up PONTIAC 6000 PART NO. 264-2725 264-2726 264-2727 264-2728 264-2725 264-2728 264-2726 264-2728 264-2727 264 2728 264-2732 264-2726 264-2732 264-2728 264-2732 Use (2) of 264-2732 CAMBER DEGREE 1/4 1/2 3/4 1 11/4 3/32" 3/16" 9/32" 3/8" 15/32" 3/32" 3/16" 9/32" 3/8" 1/2" TOE CHANGE 3/32" 7/32" 5/16" 7/16" 1/8" 7/32" 5/16" 7/16" 17/32" 17/32" 1/8" 7/32" 11/32" 7/16" 9/16" 1/8" 7/32" 11/32" 15/32" 9/16" 1-1/2 9/16" 9/16" 5/8" 21/32" 11/16" 23/32" 1-3/4 2 2-1/2 11/16" 25/32" 31/32" 11/16" 25/32" 1" 23/32" 13/16" 1-1/32" 3/4" 7/8" 1-3/32" 25/32" 29/32" 11/8" 13/16" 15/16" 1-3/16" 3 1 5/32" 1-7/32" 1-1/4" 15/16" 1-3/8" 1-13/32" 4 1-17/32" 1-5/8" 1-11/16" 1-3/4" 1-13/16" 1-7/8" TT84-1NB March, 1984 Proper installation can save clutch release bearings As a large supplier of clutch release bearings, our reputation has been built on the quality and integrity of our bearings. One of the major causes of clutch bearing failure has been traced to improper install ation procedures. This article will provide installation tips so that you can take full advantage of NAPA Bearings quality. But first, it's essential to understand the clutch release bearing's function. Clutch release bearings on most automobiles are driver activated by a linkage from the clutch pedal. (Some cars and trucks use a hydraulic system in which a clutch pedal-activated hydraulic cylinder transfers pressure to a remote hydraulic cylinder which, in turn, operates the clutch release bearing.) When activated, the bearing is pressed forward and comes in contact with the clutch release lever, or fingers. (Some cars have bearings that are constantly engaged to the clutch release lever under a very light load of 10 to 20 pounds.) These release levers pivot and pull up on the pressure plate. With the pressure plate in this position, the friction disc is released from its grip between the pressure plate and flywheel. In essence, the engine is disconnected from the transmission, enabling the driver to shift gears. There are two basic types of clutch release bearings--thrust and angular contact. The following description and diagram show you the main difference between them. In the thrust-type clutch release bearing, the main elements are two washer-shaped rings (1,2) in which the raceways for the balls are precisely ground. A housing (3) completes the bearing by holding the rings parallel, with the retainer and balls (4) sandwiched in between. The retainer spaces the balls evenly throughout the raceways. The bearing is then pressed onto the carrier (5) to complete the assembly. In the angular contact-type clutch release bearing, the main elements are the inner and outer rings (1,2). These rings also have precision ground raceways. Unlike the thrust-type bearing, the rings, the retainer (3) and balls are held together by a snap fit in the outer ring. These bearings are assembly by heating the outer ring so that the inner ring and ball assembly can be slipped under the snap. Once the outer ring cools, a non-separable assembly is produced. Then a seal or housing (4) is assembled to the outer ring. Like the thrusttype bearing, it is pressed onto a carrier (5). When either type of bearing is pressed on a carrier, the bearings must be rotating. This will reduce the possibility of raceway damage during assembly. In most cases, the thrust-type clutch release bearing will give suitable service life. However, in applications where the clutch bearing is in continuous operation, or misalignment is present, the angular contact bearing should be used. The design of the clutch release bearing will only allow for slight misalignment between the clutch release levers and the bearing. When misalignment does exist, the balls are forced to constantly change speeds. This can cause raceway damage and premature ball retainer wear. Also, excessive heat caused by friction can damage the lubricant and, ultimately, the bearing. NAPA clutch release bearings are per* manently lubricated at the factory and Tfcquire no additional lubricant. Some heavy-duty trucks may have clutch release bearing assemblies with grease fittings. Consult your manufacturer's specifications for proper maintenance procedures. Be sure that the groove inside of the bearing carrier is packed with grease. In addition, lightly coat the input shaft sleeve with lubricant. Under normal operating conditions, the bearing should have a service life at least as long as the clutch disc. Installation Checklist The following list of installation tips can ensure bearing performance and long service life: Check for misalignment in the clutch system prior to assembly. Inspect clutch release fork and replace if worn or warped. Inspect transmission input shaft sleeve and replace if worn or corroded. Tighten engine mounts to prevent loss of linkage adjustment. Inspect clutch linkage and replace any worn pivot points--lubricate as required. Pack the groove inside the bearing carrier with grease. Lightly coat the input shaft sleeve with grease. Check assembly of clutch fork and bearing. Adjust clutch free-play according to manufacturer's specifications. By making the necessary repairs to the clutch system that created the premature failure of the previous clutch release bearing, you will receive excellent performance and long service life from NAPA Bearings clutch release bearings. For futher information, write: NAPA Bearings 26555 Northwestern Highway Southfield, Michigan 48034 For technical, application or inter change information, call our answer line 1-800-521-0102 (in Michigan, call 1-800-572-9206) for fast assistance. 55 TT84-2NB March, 1984 How to analyze a clutch system by inspecting the clutch release bearing The face of a used clutch release bearing can reveal very useful information about your clutch system. We want to show you how to inspect the clutch bearing and how to interpret what you see. In an earlier Tech Tip, we discussed how the clutch system operates. As we described c|) it, the clutch release bearing contacts the Wide nS* clutch fingers (or levers) and releases the clutch as the bearing moves into the clutch CBhtact v'~------- - Figure 6 fingers. This movement along the inner face of the bearing is shown in the diagrams in Figure 1 below. This wear pattern illustrated in Figure 3 is typical of a clutch system that is operating correctly. The worn area is sometimes shiny but is mostly a rusty color. This rusty color is caused by oxidation that occurs during pattern is caused by the contact point moving because of wear on the clutch disc. If this is noticed after a relatively short time, it could indicate a problem in the clutch system. ' fretting (sliding) wear. As you see, the wear Possible causes of wide wear pattern: pattern is located within the borders of the Misapplication face and is concentric to the bearing bore. Improper adjustment The following diagrams show face wear that cindicates the presence of a problem in the clutch system. Worn or deformed clutch fingers Worn or deformed clutch fork Misalignment Excessive bearing travel Excessive clutch disc wear High Contact ^*** ^ Figure A Round Face -- Flat Fingers Figure I During this movement of the clutch bearing, the fingers slide radially on the face of the bearing. This sliding on the face results in a wear pattern on the face of the bearing. The resulting wear pattern can help diagnose a clutch system problem. The proper viewing angle to inspect this wear pattern is shown in the diagram below. The high contact pattern shown in Figure 4 is the result of the fingers contacting the bearing face on the outer edge. This can re sult in the bearing housing being worn off and/or the fingers being excessively worn. Possible causes of high contact pattern: Misapplication Improper adjustment Worn or deformed clutch fingers Worn or deformed clutch fork Clutch disc too thin (flat face) Clutch disc too thick (round face) The low contact pattern shown in Figure 5 is the result of the fingers contacting the bearing face on the inner edge. This can result in the inner sleeve of the bearing being worn and/or the fingers being excessively worn. Possible causes of low contact pattern: Misapplication Improper adjustment Worn or deformed clutch fingers Worn or deformed clutch fork Clutch disc too thin (round face) The wide wear pattern illustrated in Figure 6 is typical of a long-lived bearing. This wide Figure 7 illustrates a wear pattern that is the result of misalignment between the bearing centerline (transmission) and the clutch axis (engine). This misalignment will cause excessive wear of the bearing face and clutch fingers. It will also result in a reduction in bearing life. Possible cause of spiraling wear pattern: Misalignment As you can see, the inspection of the clutch release bearing face can give you useful information while troubleshooting a clutch system problem. In many cases, the problem can be attributed to the use of improper components in the clutch system. In some cases, a wear pattern can indicate a specific problem--for example, misalignment. By inspecting the NAPA clutch release bearing, we believe you can gain useful information and get the maximum service life from the components in your clutch system. For further information on NAPA Bearings write: NAPA Bearings 26555 Northwestern Highway Southfield, Michigan 48034 For technical, application or Inters change information, call our answer line 1-600-521-0102 (in Michigan, call 1-800-572-9206) for fast assistance. 57 BULLETIN NO. ST-85-2U JANUARY 11,1985 ANTI SKID BRAKING SYSTEM (ABS) Ford Motor Company's Lincoln Mercury Division has introduced a four wheel skid control brake system for 1985. The models equipped with the anti-skid braking system are as follows: - 1985 Continental Designer Series - 1985 Mark VII L.S.C. - 1985 Mark VII Designer Series - 1985 All V-8 Continentals being sold in Alaska. Hawaii. Oregon and Washington - 1985 All Mark VII models being sold in Alaska, Hawaii. Oregon and Washington The four wheel anti-lock brake system for Mark VII and Continental is a new compact integral power brake system which uses brake fluid for both the braking function and the hydraulic boost to the brake system. The main component parts of the system include: Master Cylinder & Hydraulic Booster Electric Pump & Accumulator Valve Body Assembly Electronic Digital Computer Reservoir (4) Wheel Sensors The idea behind ABS is to prevent overbraking, especially in panic stops. There is actually no skidding or loss of ability to steer the vehicle, regardless of the road surface. An average driver can stop in a shorter distance with ABS than a trained driver in a standard brake system. 63 n The system consists of an electronic digital microcomputer and electronic sensors at all 4 wheel positions. The system compares the individual rotation speed of each wheel during braking. When the sensor informs the computer one of the wheels is slowing down at a faster rate than the others, the computer compares the signal and determines how best to modulate fluid pressure in the appropriate line of the 3 circuit hydraulic system to prevent wheel lockup. The electronic digital computer is. in effect. 2 computers in one. If the readings on either part of the computer differ, the skid control system will be inhibited and braking will revert to the normal mode. A light on the overhead panel in the vehicle will light up to advise the driver the skid control system is inoperable. .""S 1985 LINCOLN MERCURY ABS SYSTEM The hydraulic system consists of 3 separate circuits. The left front, right front, and one which controls the rear wheels as an axle set. It is totally integrated with the funda mental hydraulics of the brake system, allowing faster response time. MASTER CYLINDER AND HYDRAULIC BOOSTER The power source for the system is provided by an electric pump charging a nitrogen filled accumulator, only as required. This is in comparison to the conventional hydro boost system where power is required by the power steering pump. There is no difference in braking feel, or efficiency, during normal stopping between the 2 systems. 64 -3- 8RAKE FLUID WARNING SWITCH 3 PIN CONNECTOR ANTI-LOCK WARNING SWITCH 2 PIN CONNECTOR MAIN VALVE 2 PIN CONNECTOR MASTER CYUNOER FEED LINE FRONT \ SOLENOID VALVE 7 PIN CONNECTOR SOLENOID VALVE BODY MASTER CYLINDER AND HYDRAULIC BOOSTER (WITH ELECTRIC MOTOR AND SOLENOID VALVE BODY) The master cylinder and hydraulic booster are arranged in the conventional fore and aft position, with the booster behind the master cylinder. The control valve for the booster is located in a parallel bore above the master cylinder centerline. It is operated by a lever mechanism connected to the brake pedal push rod. ELECTRIC PUMP AND ACCUMULATOR The electric pump is a high pressure pump design that runs at frequent intervals for short periods to charge the hydraulic accumulator that supplies the service brake system. The accumulator is a gas filled pressure chamber that is part of the pump and motor assembly. The electric motor, pump and accumulator assembly are shock mounted to the master cylinder and booster assembly. 65 -4VALVE BODY ASSEMBLY The vulvc body assembly contains 3 pairs of solenoid valves: one pair for each front wheel, and a third pair for both the rear wheels combined. The paired solenoid valves are both inlet and outlet valves with the inlet valve normally open and the outlet valve normally closed. The electrical connector receives input from the electronic digital microcomputer to pulse the various hydraulic systems as needed during anti-skid operation. RESERVOIR WITH FLUID LEVEL WARNING SWITCHES The reservoir assembly is a translucent plastic container having 2 main chambers. Integral fluid level switches are part of the reservoir cap assembly. It has 2 electrical connectors. 1 from each end of the cap. for wire harness connections. Two low pressure hoses lead from the reservoir. One hose attaches to the hydraulic pump assembly, and the other to the master cylinder housing. NOTE: THIS CONNECTOR CANNOT BE DISENGAGED LOW PRESSURE HOSES 66 -5- The reservoir is mounted to the hydraulic unit with a screw and bracket and a push-in tube outlet that seats in a grommet located in the brake booster housing. The following procedure must be followed whenever you are checking and filling the brake reservoir or bleeding the brake system: WARNING: Before servicing any components which contains high pressure, it is mandatory that the hydraulic pressure in the system be discharged. Refer to the proper procedure in the Ford Motor Company Manual. HYDRAULIC RESERVOIR CHECKING AND FILLING (a) With ignition switch on, pump the brake pedal until the hydraulic pump motor starts. (b) Wait until the hydraulic pump shuts off. , (c) Check the brake fluid level. If the level is below the max fill line, bring the level up to this line. . CAUTION: Do not fill over the max fill line. Overfilling the reservoir may cause the fluid to overflow when the accumulator discharges during normal operation. It is possible, depending on the state of charge of the accumulator, the fluid level could show above the max fill when first viewed. If this occurs, perform Steps (a) and (b) above before taking any other action. 67 6- WHEEL SENSORS There are 4 variable reluctance electronic sensor assemblies, each with a 104 tooth ring. Each sensor is connected to the electronic controller through a wiring harness. The front sensors are bolted to the front spindles by a bracket. The front toothed sensor rings are pressed onto the inside of the front rotors. FRONT WHEEL SENSORS The rear sensors are bolted to brackets which are bolted to the rear disc brake axle adapters. The toothed rear sensor rings are pressed on the axle shafts, inboard of the axle shaft flange. All the sensors have an adjustable air gap between the sensor head and tooth surface. REAR WHEEL SENSORS 68 7 ELECTRONIC CONTROLLER The electronic controller is ;i self-contained unit consisting of 2 microprocessors and the necessary circuitry lor their operation. The controller monitors system operation during normal driving as well as during anti-lock braking. Under normal driving conditions, the microprocessors produce short test pulses that check the electrical system to the solenoid valves. These test pulses do not cause any mechanical reaction in the system. When a wheel begins to lock up. a signal is triggered from the controller to the solenoid valves and opens the main valve. This supplies pressure to a reaction sleeve which, in turn, results in moderate pulsations in the brake pedal. It is also accompanied by a change in pedal height. During normal braking, the brake pedal feel will be identical to a standard brake system. PRECAUTIONS WHEN SERVICING ABS SYSTEM NOTE: The hydraulic pump maintains a pressure between 2,030 psi and 2,610 psi in the accumulator. Care must be taken when opening the rear bleeder screws, due to the high pressure available from the fully charged accumulator at the bleeder screw. BRAKE SYSTEM BLEEDING - The front brakes can be bled in the conventional manner, with or without the accumulator being charged. - Bleeding the rear brakes requires a fully charged accumulator or they must be pressure bled using a pressure bleeder attached to the reservoir cap opening with a minimum of 35 psi. - When pressure bleeding, the 35 psi minimum must be maintained on the system. With the brake pedal in the at rest position and the ignition switch in the off position, open the rear bleeder screws for 10 seconds at a time. Once an air free flow of brake flu id has been accomplished at each caliper, close the bleeder screws and place the ignition switch in the run position. - Pump the brake pedal several times to complete the bleeding procedure. - Siphon off the excessive fluid in the reservoir to adjust the level to the max level with a fully charged accumulator. ABS braking systems are new to the American automobile. The information contained in this bulletin is to help you understand the system. Diagnostic and repair information will be available in the future. We will keep you up-to-date on these items. Tom Golden Technical Service Manager 69 UNITED PARTS DIVISION * McHENRY, ILLINOIS 60050 ECHLIN INC. BRANFORD, CONN. McHenry, III. Litchfield, III. Toronto Blackburn Waldorf Mexico City Caracas Sao Paulo Johannesburg 70 Printed in U SA BULLETIN NO. ST-85-16U AUGUST 12, 1985 BRAKE SYSTEM DIAGNOSIS After installing a new master cylinder, a low or spongy brake pedal is a common complaint. The following procedure will allow quick, effective troubleshooting: SYSTEM CHECK FOR AIR -- Remove master cylinder reservoir cap and fill reservoir to 1/8" of the top. -- Replace cap loosely and rapidly pump the pedal (25) times. Hold pedal in applied position on the 25th pump. -- Remove reservoir cap. Release brake pedal while assistant observes reservoir. Normal compensating. A slight ripple verifies system contains no air. A geyser of fluid 6--7" jump in fluid indicates air trapped in that portion of system. -- Repeat test (3) times to verify results. MASTER CYLINDER CHECK FOR OPERATION -- Remove outlet lines at master cylinder. -- Block outlet ports of master cylinder with bleeder screws or plugs. Check for leaks at plugs. -- Pump brake pedal until hard. (No pump condition.) -- Allow vehicle to stand (15) minutes. -- Recheck for same hard pedal. Master cylinder is good -- High hard pedal. Master cylinder is bad -- Spongy or sinking pedal. 75 2- - VERIFY INDIVIDUAL SYSTEMS (REAR BRAKES) -- Remove plug and install rear brake line. -- Bleed system at rear wheel cylinders. Normal system results -- High hard pedal. NOTE: Adjust rear brakes prior to bleeding system. Abnormal results -- Continue diagnosis. -- Apply emergency (parking) brake. Note any change in pedal height. Pedal height increase indicates oversized brake drum. -- Remove rear brake drums, check for oversize. -Replace as necessary. VERIFY INDIVIDUAL SYSTEMS (FRONT BRAKES) -- Remove remaining plug and install front brake line. -- Bleed system at calipers. -- Visually inspect bleeder screw position. Bleeder screw must be at highest position. Normal system results -- High hard pedal. Abnormal results -- Continue diagnosis. -- Carefully pinch off brake hoses at front calipers. -- Check brake pedal. Normal system results -- High hard pedal. -- Remove one front brake hose -- pinch off. Normal system -- High hard pedal. A bnormal system -- Bleed caliper for trapped air. -- Remove remaining front brake hose -- pinch off. Normal system -- High hard pedal. A bnormal system - Bleed caliper for trapped air. 76 -3The diagnostic procedure listed breaks down the typical hydraulic system into (3) separate sub-systems: 1. Master Cylinder 2. Rear Hydraulic System 3. Front Hydraulic System Each system must obtain a high hard pedal before continuing. Following this diagnostic procedure will enable you to quickly and accurately diagnose problems. Tom Golden Technical Service Manager 77 NAPA TECHNICAL TIP NN-10-2-82 GM QUICK TAKE-UP MASTER CYLINDER Beginning in 1980, GM introduced low drag calipers to retract the caliper piston further so that the brake pads don't drag against the rotor. Because of this change, to improve fuel economy, GM vehicles X, J, and some 1981-82 models and light trucks except diesels have a quick take-up master cylinder. This master cylinder must be bench bled and a bleeding sequence followed after overhauling or replacing the master cylinder. There are two types of quick take-up master cylinders -- one with four outlet ports and the other with two outlet ports. To bench bleed a master cylinder with four outlet ports, plug the two proportioner ports and lead tubes from the front outlet ports to the reservoir. The other type of master cylinder can be bled by leading tubes from tne outlet ports to the master cylinder reservoir. Bench bleed the cylinder until there is no air. Remount the master cylinder and replace the hydraulic lines. With a power bleeder, use United's bleeder adapter with about 20-25 psi in the tank. On the four outlet port master cylinder bleed the right rear, left front, left rear, right front wheels. And on the two outlet port master cylinder bleed the right rear, left rear, right front, left front wheels. Using these bleeding procedures will get all the air out of the brake system. If using manual bleeding techniques, the master cylinder may be bled on the car. The strokes should be quick strokes with a slow return. It is necessary to wait 15 seconds between each stroke. Bleed the wheels in the same se quence as mentioned, waiting fifteen seconds between pumps to allow fluid to return past the quick take-up valve. To bleed the X/J/A master cylinder, the two front (upper) master cylinder lines have to be purged of air prior to bleeding wheels. Disconnect the left front port and allow fluid to flow out. Reconnect the tube and tighten. Press the brake pedal, and, as it is held down, loosen the con nection again to purge the air. Retighten it and slowly release the pedal. Wait fifteen seconds and repeat the procedure. Continue until all the air is removed from the master cylinder bore7""tloing the right front connection in the same way. Because these quick take-up master cylinders are mounted at an angle, it is necessary to raise the rear of the car so the master cylinder is level before the master cylinder or wheels are manually bled. In summary, when bench bleeding and using a pressure bleeder, it is necessary to use the proper bleeding se quence. When manually bleeding the master, it is neces sary to purge the lines of the master cylinder waiting 15 seconds between pedal applications, and then bleeding each wheel in sequence waiting 15 seconds between strokes until all air is removed from the brake system. 10 MM THREAD PROPORTIONER VALVE ASSEMBLY 13 MM THREAD PROPORTIONER VALVE ASSEMBLY QUICK TAKE-UP VALVE (NOT SERVICEABLE) GM 1981-1982 MODELS AND SOME LIGHT TRUCK MODELS 79 TT Brake System Bulletin No. JO, TR-80-1R . DATED JANUARY 1, 1980 TO: ALL NAPA JOBBERS AND MECHANICS PRODUCT: DISC BRAKES SUBJECT: NOISE ~~ A VIBRATION or PULSATION in the front end during braking has come to indicate to experienced brake mechanics a condition caused by warped disc brake rotors. This condition could more accurately be defined in terms of lateral runout and paral lelism. Lateral runout is the movement of the rotor from side to side as it rotates. A rotor with excessive runout will wobble pushing the disc brake piston back into the bore. Additional brake pedal travel and vibration will result. The symptoms of lateral runout on floating caliper brakes are somewhat less noticeable because their calipers will move from side to side with the rotor. There is, however, more wear to bushings on floating calipers due to the excessive move ment created by an extreme lateral runout condition. PARALLELISM refers to variations in the thickness of the rotor. This must not be confused with the minimum thickness specification or discard dimension now stamp ed on all disc brake rotors. The circumferential thickness variation or parallelism is a very close tolerance and generally must be within .0005 to .0007 in. (.01270 to .01778 mm). A thickness variation exceeding the specification can result in a FRIGHTENING VIBRATION DURING BRAKING. As the thin section of the rotor passes between the brake disc pads it allows them to move in closer together. Then as the thicker section of the rotor is forced past the pads it exerts a pressure against the pads. This momen tarily creates a greater braking effort and at the same time pushes the pads back. Once the thick section of the rotor passes the pads, the thinner section rolls through more easily. This passing of thick and thin sections of the rotor creates a VIBRATION or pulsation of the brake. This condition can also be felt as a short SLIDE before the car comes to a dead stop. It is interesting to note that the effects of thickness variation are more noticeable to the driver than the effects of lateral runout. IT IS NOT UNUSUAL WHEN A ME CHANIC JUST REPLACES A SET OF DISC BRAKE PADS ONLY TO HAVE THE CUS TOMER BACK IN A FEW HOURS OR DAYS, COMPLAINING OF A STRANGE NOISE. NEVER JUST HANG DISC PADS BEFORE A COMPLETE CHECK OF EVERY CALIPER AND ROTOR IS MADE. Yours truly, PAUL L. LeCOUR Product Manager 83 ------ AutoCane NN-2-12-79 DISC BRAKE MAINTENANCE-OFF THE ROAD With the increased availability of disc brakes on both Ax2 and bxk trucks, we feel there are some problem areas which should be pointed out to you. Trucks equipped with disc brakes, that are home based on farms or used in localities where the roads are poor or non-existant, are subjected to severe operating conditions and the following preventa tive maintenance should be practiced by their owners. 1. Keep dust shields free of grass, hay or other field trash. Dust shields are designed to help cool the rotors and must be kept clear. 2. After leaving muddy areas check rotor cooling fins to see if they are clean. If they are packed with mud, hot spots can develop and the rotors may become distorted or fracture from the heat, result ing in erratic braking. 3. If the vehicle is used in a dusty area, frequent checks of the disc pads are in order, as pad wear is unusually fast in these surround ings. (OVER PLEASE) 85 /<. Brake systems (whether drum or disc) in these areas should be flushed completely once a year and possibly more in some cases, to keep amount of contamination in the brake system at a minimum. This also insures that bleeder screws will not become frozen. As this information is in the line of preventative maintenance, rather than a Service Tip, pass the word along when it is relevant to the area you are in.