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vv>s ' doa'erndcpo^ . bV ^e *Uftn<j Uoco^ s^'ons. \ ^ )W *n S^`cc, * . ' ** / - 6afa9es t pA^e sCf.fORt>-"518 SERVICING FORD o"T-s The mark of a good brake job, it's been said, is not one you'll stand behind, but rather, one you'll stand in front of! No one, of course, should take the saying too litcially; that is, check the quality of thcii work by standing in fionl of a vehicle. It docs, howcvci, make a valid point. After you service a customers biakc system, you should shaic the owner's faith in the cat's ability to stop. IN THIS ISSUE FORD BRAKE SYSTEMS.......................... 2 Drum Brakes . . .. 2 Disc Brakes.......................................... 4 Hydraulic System ................................7 SERVICE PROCEDURES.......................... 8 Drum Brakes........................................... 8 Disc Brakes . .. ........... 10 Hydraulic System ...............................IS FORD and AUTHORIZED REMANUFACTURED FORD BRAKE LINING ..................................... 16 Be sure and tile tins and future bulletins tor ready reference It you have any suggestions lor additional information that you would like to see included in this publication, please write to Autolite Ford Pads Division of Ford Motor Company, Merchandising Services Dept. P 0. Box 3000, Livonia. Michigan 48151. The description and specifications contained in this book were in effect at the time the publication was approved for printing. The Ford Motor Company, whose policy is one ot continuous improvement, teserves the right to dis continue models at any time, or to change specifications or design without notice and without incurring obligation Autolite ma COPYRIGHT 1909 TORD MOTOR COMPANY DtARDORN, MICHIGAN VOL 69 MSD 19 LIT HO IN U S A 2 much for granted 1 cw know when their brakes need service T hey expect them to go on, month after month, providing all the stopping power they need. Unlike othet components that may malfunction, it only takes ONI. instance with brakes to perhaps icsull in serious consequences I-'or that icason, biakc service must be performed correctly. 1 o help you in this vital service, "Shop T ips'' presents Bait 1 of a two-part article on 1 old Motor Company passenger car biakcs Next month, I ebruary Shop 1 ips will contain Part 11 which will include Servicing Cortina Biakc Systems s~ FORD BRAKE SYSTEMS MAJOR COMPONENTS & OPERATION DRUM BRAKES Because of their exclusive use until recently, most late model 1 ord-built cars use drum brakes (1 lg. I) both front and rear. 1 hey feature a duo servo, scif-cncrgi7ing biakc shoe design. 1 o see how it works, let's look at a right-hand brake assembly as the vehicle is moving forward and the brakes arc applied. I igure I--Duo Seno Biakc Assemblies with Self Adjusting Mechanisms BRAKE SYSTEMS ... PART I Self Energizing Brakes (1) Hydraulic pressure forces the wheel cylinders (2) This is also a duo, or double, servo brake (3) So while the primary shoe is energized by its outward, moving the primary shoe against the That's because the frictional force of the own frictional force, the secondary shoe is rotating drum. Friction causes the primary primary shoe through the adjusting screw energized by its own friction, AND by the shoe to shift downward (clockwise) in the direction of drum rotation, as far as the assembly, and the friction on both shoes, helps press or wedge the secondary shoe force of the primary shoe. As a result, the secondary shoe has about twice the braking anchor pin permits through the adjustor and against the drum effect as the primary That's why secondary secondary shoe, lhe primary shoe tends to shoe linings are longer. To even out wear, <L resist, and in so doing, makes even further contact with the drum. This is called "self energizing," or servo action. But there's lining material for the primary shoe usually has a higher coefficient of friction than secondary shoe linihg more. Self Adjustment Mechanism Beginning with 1961 models, 1 ord-built cars incorporate a self adjusting mechanism to keep brake shoes adjusted to the proper gap from the dium This adjustment occurs automati cally when the car moves backward and the brakes arc applied. T he linings tend to follow the rotating drum counterclockwise (Fig. 2). T his "wrap around" action forces the upper end of the primary shoe against the anchor pin. At the same time, the wheel cylinder pushes the upper end of the secondary shoe and cable guide outward, away from the anchor pin (1 ig. 3) T his movement of the secondary shoe causes the cable to pull the adjusting lever upward, and AGAINST Till INDOl T HE. T OOT II ON Till. ADJUST - ING SCRHW ST AR Will FI. As lining wear increases, the upward travel of the adjusting lever increases. I igure 2- Self Adjustors Operate When Brakes Are Applied In Reverse 3 SERVICING FORD '"X ligure 3-- Secondly Shoe Movement Pulls Adjusting l ever Upward When the lever can move upward far enough, it passes over the end of the tooth and engages it. When the brake is released, the adjuster spring pulls the adjuster lever downward. The lever turns the star wheel causing the shoes to expand. The star wheel turns one tooth at a time as the linings wear. If the lever can not move upward far enough to make an adjustment, it slides down the end of the star wheel tooth until the linings have worn enough to allow the lever to move up far enough to engage the tooth. Fixed Caliper 1 ixed caliper disc brakes arc used on all l'ord Motor Company cars from 1965 thru 1967. Corlina models (I ig. 5) and Lincoln Continental models (1 ig 6) continue to use a fixed caliper brake on 1968-69 models. This brake is called a '`fixed'' caliper type because the eomplete caliper assembly is rigidly bolted to the steering wheel spindle. The caliper assembly consists of two caliper halves bolted together Facli half has a pair of pistons (I ig. 7). Square cross-section seals around each piston perform three important functions: 1. Hydraulically seal piston and cylinder. 2. Return pistons to released position when hydraulic pressure is released 3. Maintain shoes in correct adjustment at all times (much like drum brake automatic adjusters). More about this under floating caliper disc brakes. Internal passages in the caliper housing and an external transfci tube between the two caliper halves hydraulically connect the cylinders Fach caliper assembly has one bleeder screw and fluid inlet fitting Shoe and lining assemblies arc located between parallel machined abutments within the caliper. T abs on the outer ends of the shoe assemblies radially support the shoes. T lie shoes slide axially in the caliper abutments by means of the tabs, which ride on machined ledges (bridges) when hydraulic pressure is applied to the pistons The shoes thus squeeze against the rotoi to stop the wheel. Clips (1 ig. 8) attached to the top of the caliper retain the shoe and lining assemblies. The lining is either riveted or bonded to a metal plate (shoe). It is replaced as a unit. The cast iron rotor has forty fins for ventilation. It's attached to, and rotates with, the wheel hub. A splash shield bolts to the spindle to prevent road contaminants from contacting the inboard rotor and lining surfaces. The wheel protects the outboard surfaces. f'tgure 4- Adjusting 1 ever Moves Povnwaid 7o Turn Star Wheel DISC BRAKES lord introduced front disc brakes in 1965 on Mustang, T hunderbird and 1 incoln Continental models. T hey have been made available on moic models caelt succeeding year, until all 1968-69 passenger cars have them as either standard or optional equipment. I -250 (4x2) and I -350 trucks also use front disc brakes. As with passenger cars, rear biakes arc drum type. 4 BRAKE SYSTEMS . . . PART I CALIPER ASSEMBLY *20118 RH 20M9.L M CALI PER PARTS -JBI30 R H -JBI2M H 9105 9106 ROTOR SPLASH SHIELI JK004-R H 9K005-L H f figure 6--fixed Caliper Disc Drake- Exploded View With Basic Part Numbers C COVER-1130 CALIPER TO ROTOR CLEARANCE CALIPER HOUSING PISTON SHOE LINING PISTON SEAL -TRANSFER TUBE PISTON DUST BOOT RETAINING GROVE CALIPER DUST BOOT RETAINER Figure 7- Fixed Caliper- Sectional View rygure 8- itxed Caliper Disc Brake Assembly SERVICING FORD o Floating Caliper All 1968-69 I oid Motor Company cais, except Cortina and I incoln-C'ontincntal models, ntili/c a `floating'' calipci disc biahc (I ig 9) It functions much difTcicntly than the fixed type 'I lie caliper consists of a onc-piccc housing- not a twopiece assembly. And it's not bolted to the wheel spindle- it's free to move mboaid and outboard (float) parallel to the spindle axle, as the biakcs aic applied and idcascd. Only one piston is used instead of four 1 he onc-piccc caliper housing slides in and out a fraction of an inch on two caliper locating pins that scicw into cars on the caliper housing, and pass thiough insulatois fitted into holes in the anchoi plate 1 he anchoi plate bolts to the wheel spindle Stabih/cis coniiol the call pci's position m iclation to the lotoi Two types of stahili/ers aic used as shown in I igurc 9 1 hey arc fastened to the caliper by the caliper locating pins and to the anchor plate by two cap screws. The single piston fits into a bore in the inner portion of the caliper (I 10) 1 he inner brake shoe and lining assembly fits against the piston and has cars on the outer ends that rest on the anchoi plate bosses T wo hold-down clips, bolted to the anchor plate, hold the shoe m position 1 he outer shoe and lining, which is tongci, attaches to the outer legs of the caliper 1 lie floating caliper luakc works something like a "C" clamp When the brakes aic applied, hydraulic picssurc forces the piston outivn/(/, moving the inboard shoe and lining into contact with the rotor No appreciable braking effect occuis, howcvci, until more hydiaulic fluid enters behind the piston It docs not cxcit greater picssuic force on the piston, but because the caliper can "float," the additional hydraulic prcssuic develops a icaction foicc that moves the calipci inwani. foicing the out board shoe and lining against the rofoi (I ig II). Additional hydraulic pressure foiccs both linings to grip the rotor m a "sandwiching" action to stop the wheel. FLOATING CALIPER HOUSING OUTBOARD SHOE AND LINING V. / I igurc 9- l baling Caliper Brake Assembly 6 o BRAKE SYSTEMS PART I [PISIONI- caliper housing! [quiboard' SHOE AND LINING INBOARD SHOE AND . LINING f "ROIORr .ANCHOR PLATE J ;hub; DUST BOO! ] figure 10- /loohftg (attper Assembly- Sectional View Self-Adjusting Disc Brakes Caliper piston seals (1 ig 12) perform the self-adjusting action on disc brakes, instead of a mechanical set-up such as used in drum brakes. During brake application, the caliper piston seal distorts as hydraulic pressure pushes the piston out for the distance required to press the brake shoes against the rotor. Removing the foot from the brake reduces pressure and the seal returns to a relaxed position As the seal relaxes, or rolls back, it moves the piston inward in the caliper housing bore. As the piston moves inward, the stabilisers position the caliper housing and outci brake shoe lining assembly on the rotor, to automatically maintain the correct clearance. This retracting action, however, is always limited by rotor runout and amount of seal rollback, or relaxation, that in turn causes the piston to travel back. PISTON PISTON TRAVH DETERMINED BY LINING TO ROTOR CLEARANCE piston return determined by SEAL PULLBACK HYDRAULIC pressure figure JI-floating Caliper Operation figure J2~ Caliper Piston Seals Control Self Adjustment Hydraulic System Since 1967,1 ord Motor Company cars have used a dual master cylinder on disc (and drum) brakes. T he front cylinder furnishes hydraulic pressure to the rear brakes; the rear cylinder pressure to the front brakes. Thus, if a malfunction occurs in either system (sensed by a differential valve that flashes a red light on the instrument panel when the brakes arc applied), the other hydraulic system will still operate and stop the car. All disc brake systems use a proportioning valve (t ig. 13) to provide balanced braking action between the front (disc) and rear (drum) brakes. T he proportioning valve reduces pressure at the rear brakes. T his reduced pressure balances the sclf-cncrgiring rear drum brake action with the non-cncrgi7ing front disc brake action. Lincoln-Continental and 1'-250 and 350 Truck models only use metering valve (l ig. 13). It prevents the front disc brakes from applying until master cylinder pressure reaches about 120 psi. T his delay prevents the front brakes from performing all the braking action at low-speed stops, thereby increasing the disc brake lining life. SERVICING FORD SERVICE PROCEDURES DRUM BRAKES Cleaning and Inspection 1. Remove the wheel from the drum, then remove the drum from the brake with a gentle rocking motion. If the drum will not come off, knock the iubber plug out of the brake carrier plate with a punch. Jnscil a nairow screwdriver through the slot and disengage the adjusting lever away from the screw, back oflf the adjusting scicw with a brake adjusting tool (lig. 14) He extremely careful not to burr, chip or damage the notches in the adjusting screw; otherwise the self-adjusting mechanism may not function property 2. Brush all dust from the backing plates and interior of the brake drums. 3. Inspect brake shoes for excessive lining wear or shoe damage. If the linings arc worn within 16-inch of the rivet heads or if the shoes arc damaged, they must be replaced 1 mings contami nated will) oil, grease or biakc fluid must be replaced. Replace linings m axle sets, ltcforc lining replacement, check drum diameter to determine if oversire linings should be installed. 4 Cheek brake shoes, retracting springs, hold-dow'n springs and drum for signs of overheating. If shoes have a slight blue coloring, indicating ovciheating, it's advisable to replace the retracting and hold-down springs. Overheated springs lose their pull and if not replaced, could cause the new lining to wear pi ematurely. 5. If the vehicle has 30,000, or more, miles of operation on the brake linings, oi if there arc signs of overheating when relining the brakes, disassemble the wheel cylinders and inspect for wear and dirt. Replace the cylinder cups, to avoid the possibility of premature future problems. 6. Inspect all other brake parts and replace those that appear worn or damaged. 7. Inspect the brake drum for roughness If necessary, refinish. If contaminated with dirt, oil or gicasc, wipe clean with cloth soaked in denatured alcohol Brake Drum Refinishing Minor scores on a biakc drum can be removed with sandpaper. However, an excessively scored drum, or one with a total indicator runout over 0 007-inch should be turned down Remove only enough metal to eliminate the scores and true up the drum. 7 he refimshed drum diameter must not exceed 0.060-inch oversize Cheek the inside diameter of the brake drum with an accurate brake drum micrometer tool (such as Rotunda l'Rh 1431). If the drum diameter is less than 0.030-inch oversize after rcfinishing, install standard size lining. If the drum diameter is 0. 030.0.060-inch ovcisizc after refinishing, oversize linings must be installed. After turning down drum, wipe the refimshed surface with a cloth soaked in clean dcnatuicd alcohol. If one drum is turned down, the opposite drum on the same axle should also be cut down to the same size. Installing New Brake Drums If a brake drum must be replaced with a new one, be sure to remove the protective coating from the new drum. Use a solvent such as carburetor degreaser 7 hen, sandpaper to insure no residue remains. Wipe the drum with a cloth soaked in dcnatui cd alcohol. Install new bearings and a new grease seal m front drums. Brake Shoe Relining Brake linings worn to within 16-inch of the rivet head, or less than 0 030-inch thick (bonded linings), or linings contaminated with brake fluid, grease or oil must be replaced. Worn linings will score the drum and cause additional repairs When it's necessary to replace linings on one wheel, they must also be replaced on the wheel on the opposite side of the vehicle Inspect brake shoes for distortion, cracks, or looseness. If any of these conditions exist, the shoe must be replaced. Ho not attempt to repair a defective brake shoe. 1 inings may be replaced by either installing new linings on the shoes, or using new linings already attached to the shoes. Hath new lord linings and lord Authorized Remanufacimed linings are pt e-gr outid and no fur ther gr aiding is r cqiin ed to match dr urn surfaces. If new linings arc to be attached to shoes, use the following procedure. 1. Wash brake shoes thoroughly in a clean solvent. Remove all burrs or rough spots from shoes. 2. Cheek the inside diameter of the brake drum with a brake drum micrometer (such as Rotunda 1 Rf. 1431). If the diameter is less than 0.030-inch oversize, standard size linings may be installed. If the diameter is 0.030-0 060-inch oversize, then oversize linings must be installed. 3. Position the new lining on the shoe. Starting in the center, insert and secure the rivets, working alternately towards each end. 4. Cheek the clearance between the shoe and lining. 7 he lining must seat tightly against the shoe with not mote than 0.008mch clearance between any two rivets Brake Shoe Installation and Adjustment Since they contain similar parts (except for the parking brake components in rear brakes), front and rear brakes arc assembled much the same way. The self-adjusters require manual adjust ment only after brake shoes have been refined, replaced, or when the length of the adjusting screw has been changed while performing some other service operation. BRAKE SYSTEMS... PART I Installation 1. Rcforc installing the rear brake shoes, assemble the parking brake lever to the secondary shoe and secure with the spring washer and letainmg clip 2 Apply a light coating of high-tcmpcialurc grease at the points where the brake shoes contact the backing plate ' Position the brake shoes on the backing plate and secure the assembly with the hold down spnngs. On the rear brake, install the parking btakc link and spring, back off the parking brake adjustment then connect the paikmg brake cable to the parking brake lever (lug. 1). 4 Install the shoe guide (anchor pm) plate on the anchor pin when so equipped. 5 Place the cable eye ovci the anchor pin with the ci imped side toward the backing plate. 6 Install the pi unary shoe to anchoi spring (Pig 15) 7. Install the cable guide on the secondary shoe web with the flanged hole fitted into the hole in the secondary shoe web. T bread the cable around the cable guide gioovc (I ig 1). It is imperative that the cable be positioned in this groove and not between the guide and the shoe web. 8. Install the secondary shoe to anchor spring with the tool shown in Pig 15. lie certain that the cable eye is not cocked or binding on the anchor pin when installed. All parts should be flat on the anchor pm. Remove the brake-cylinder clamp. 9. Apply high-temperature molybdenum disulfide grease (1 ord Part No. CIAZ-19590-11) to the threads and the socket end of the adjusting screw. Turn adjusting screw into adjusting pivot nut to the limit of the threads and then back off */j turn. Interchanging the brake shoe adjusting screw assemblies from one side of the vehicle to the other would cause the brake shoes to retract rather than expand each time the automatic adjusting mechanism operated. '1 o prevent installation on the wrong side of the vehicle, the socket end of the adjusting screw is stamped with an R or 1. (P"ig. 16). The adjusting pivot nuts can be dis tinguished by the number of grooves machined around the body of the nut. T wo grooves on the nut indicate a right thread: one groove indicates a left thread. 10 Place the adjusting socket on the screw and install this assembly between the shoe ends with the adjusting screw toothed wheel nearest the secondary shoe. 11. Hook the cable hook into the hole in the adjusting lever. The adjusting levers are stamped with an R or 1. to indicate their installation on right or left brake assembly (Pig. 16). / igurc 1C - Adjustmg Screw and /.ever Identification 1? Position the hooked end of the adjuster spiing completely into the laige hole in the primary shoe web. '1 he last coil of the spring should be at the edge of the hole. Connect the loop end of the spring to the adjuster lever hole. 13. Pull the adjuster lever, cable and automatic adjuster spring down and toward the rear to engage the pivot hook in the large hole in the secondary shoe web (Pig. 1). 14. After installation, check the action of the adjuster by pulling the section of the cable between the cable'guide and the anchor pin toward the secondary shoe web far enough to lift the lever past a tooth on the adjusting screw wheel. 1 he lever should snap into position behind the next tooth, and release of the cable should cause the adjuster spring to return the lever to its original position. This return action of the lever will turn the adjusting scicw one tooth. If pulling the cable docs not produce the action described, oi if the lever action is sluggish instead of positive and sharp, check the position of the lever on the adjusting screw toothed wheel With the brake in a vertical position (anchor at the top), the lever should contact the adjusting wheel >fo inch (plus or minus kib inch) above the centerline of the screw. If the contact point is below this centerline, the lever will not lock on the teeth in the adjusting screw wheel, and the screw will not be turned as the lever is actuated by the cable. To determine the cause of this condition: a. Cheek the cable end fittings. 1 he cable should completely fill or extend slightly beyond the crimped section of the fittings If it docs not meet this specification, possible damage is indicated and the cable assembly should be replaced, b Cheek the cable length. On Ford, Mercury, 1 hunderbird, Continental Mark 111, and Lincoln Continental models, the cable should measure 11 >/g inches (plus or minus kr inch) from the end of the cable anchor to the end of the cable hook. On P'airlanc, Montego, Falcon, Mustang, and Cougar models the cable should measure 8% inches on 9 inch brakes or 9% inches on 10 inch brakes from the end of the cable anchor to the end of the cable hook. c Check the cable guide for damage. The cable groove should be parallel to the shoe web, and the body of the guide should he flat against the web. Replace the guide if it shows damage d. Cheek the pivot hook on the lever. 1 he hook surfaces should be square with the body of the lever for proper pivoting Replace the lever if the hook shows damage. c. Sec that the adjusting screw socket is properly seated in the notch in the shoe web. SERVICING FORD When adjusting the rear biakc shoes, check the parking brake cables for proper adjustment. Make sure that the cquali7cr operates freely. To adjust the brake shoes1. Use a tool such as Rotunda Tool 1IRK 8650, (1'ig. 17) tc determine the inside diameter of the drum braking surface 2. Reverse the tool as shown in 1 ig 17 and adjust the brake shoe diameter to fit the gauge Hold the automatic adjusting lever out of engagement while rotating the adjusting screw, to prevent burring the scicw slots Make sure the adjusting screw rotates freely. If necessary, lubricate the adjusting screw threads with a thin, uniform coating of high temperature molybdenum disulfide gicasc. 3. Rotate Tool I IRK 8650 around the brake shoes to be sure of the setting. A. Apply a small quantity of high temperature molybdenum disulfide gicasc to the points whcic the shoes contact the backing plate, being careful not to get the lubricant on the linings 5. Install the drums. Install Imncrman nuts and tighten securely. 6. Install the wheels on the drums and tighten the nuts to specification. 7. Complete the adjustment by applying the brakes several limes with a minimum of 50 lbs. pressure on the pedal while backing the vehicle. Aflci each stop the vehicle must be moved forward. 8 After the brake shoes have been piopcrly adjusted, check the operation of the brakes by making scvcial stops while opciating in a forward direction. Disassembly 1. Remove the links and the rubber boots from the ends of the brake cylinder. Remove the pistons, cups, and return spring from the cylinder bore (1-ig. 18) 2. Remove the bleeder screw from the cylinder. figure 18--Typical Wheel Cylinder Inspection 1. Wash all pails in clean brake fluid Dry with compressed air. 2 Replace scored pistons Always replace the rubber cups and dust boots. 3, Inspect the cylindct bore for score marks or rust. If either condition is present the cylinder bote must be honed llowcvci, the cylinder should not be honed more than 0 003 inch beyond its original diameter. 4. Check the bleeder hole to be sure that it is open. Assembly 1. Apply a light coating of specified brake fluid to all internal parts 2. 1 bread the bleeder screw into the cylinder and lighten securely 3. Insert the return spring, cups, and pistons into their respective positions in the cylinder bore (Fig 18) Place a boot and link over each end of the cylinder. Install shoes and return spiings Bleed the brake system. DISC BRAKES Fixed Caliper Cleaning and Inspection Linings Wheel Cylinders Wheel cylinders should not be disassembled unless they are leaking or unless new cups and boots arc to be installed. It is not necessary to remove the brake cylinder from the backing plate to disassemble, inspect, or hone and overhaul the cylinder. Removal is necessary only when the cylinder is damaged or scored beyond repair. Figure 19--Removing fixed Caliper Shoe and Lining BRAKE SYSTEMS... PART I lixcd caliper linings can be cheeked without removing the caliper assembly. After removing the wheel and tire (being careful to avoid damage or interference with the caliper splash shield, bleeder screw fitting or transfer tube), remove the caliper splash shield. Apply a steady inward prcssuie against each shoe and lining assembly toward its respective caliper housing on each side of the rotor. Maintain pressure for at least a minute. Jf pistons do not move in easily, force them in with water pump pliers. Grasp the metal flange on the outer end of the shoe with two pairs of pliers and pull the shoe out of the caliper (I ig. 19). Visually inspect the shoe and lining assemblies. If the lining material has worn below specifications, or if the lining shows evidence of brake fluid contamination, replace shoe and lining assemblies on HO'JJl front wheels. To check thickness, make three mcasuicmcnts with micrometer across the middle section lake one reading at each side and one in the center. If the assembly has worn to a thickness of 0.231-inch (shoe and lining together) or 0.066-inch (lining material only) at one of the three measuring locations, icplacc all (4) shoe and lining assemblies on HO! )1 front wheels Rotor Runout To check rotor runout, first eliminate all wheel bearing end play by tightening the adjusting nut. Nut should be just loose enough to allow rotor to turn Clamp a dial indicator to the caliper , 'rousing so that the stylus contacts the rotor approximately 1(i, .nch fronrthcouter edge.Rotate the rotor and take an indicator " reading. If it exceeds 0.003-inch total lateral runout, replace or resurface the rotor. An appioved tool for refinishing l ord disc brake rotors is Rotunda Disc llrakc Attachment 1 RI.-2249-2. 1 he step-by-step resurfacing procedure provided with the tool must be adhered to. 1 he finished braking, surfaces of the rotor must be flat and parallel within 0.0007-inch; lateral runout must not exceed 0.003-inch total indicator reading, and the surface finish of the braking surface arc to be 80/15 micro inches, figure 20 illus trates minimum limiting dimensions that must be observed when removing material from the rotor braking surface Dimen sion "R" is from the inboard bearing cup to the inboard rotor face. Dimension "A" is from the outboard rotor surface to the inboard bearing cup. After finishing the rotor runout check, be sure to readjust the wheel bearings to prevent bearing failure. Proper wheel bearing adjustment is extremely important with disc brakes, as too much play may cause excessive brake pedal travel and other problems. Also cheek the rotor for icormg. Minor scores can Sii* -''be removed with a fine emery cloth If excessively scored, either refinish or replace the rotor. BEARING CUP DIMENSION "B1 0 744 MINIMUM (l*C4 W UNCCXN CO*TIN(Nt*l IM5PfOftO MftCvAD 0 710 M;INJMIMJUhMOittBiffO) 1 117 MINIMUM mCOc*U>C*M>MCuOSW7ACfAL1C*O67n HlRlUtt) DIMENSION "A1 0 MS MINIMUM 04)2* MINIMUM O0CSA7 tHUNMOmftO) 0 402* MINIMUM (I9C4 6 7 MUStANG) f igure 20- I ixed Caliper Rotor l.imiting Dimensions Caliper Visually check the caliper If the caliper housing leaks, it should be replaced. Jf a seal is leaking, the caliper must be disassembled and new seals installed If a piston is schcd in the bore, a new caliper housing is required. 1 he two halves of the caliper assembly must never be separated. Damage or failure of one requires replacement of both as a unit Cheek the caliper to spindle attaching bolts for tightness.! orque to specifications shown in the following chart. Fixed Caliper to Spindle Attaching Bolt Specifications (Ft. Lbs.) Fold, Mercury, thunderbird and Lincoln Continental, Mustang, Cougar, Fairlane and Comet Caliper to Bracket Bracket to Spindle 1965 90 115 45 60 35-45 1966 90-115 45-60 35-45 1967 IPO-130 1968 110-140 (Lincoln only) 1969 110-140 (Lincoln only) 45-60 35-45 Brake Hoses * Cheek brake hoses for signs of cracking, leaks or abrasions. Replace as required. Removal, Overhaul and InstallationCaliper Removal 1. Remove the wheel and tire assembly from the hub and rotor. He careful to avoid damage or interference with the caliper splash shield, bleeder screw fitting or transfer tube. 2. Disconnect the steel brake line transfer tube from the caliper. l.eave the steel tube connected to the brake hose connector and bracket assembly. 3. Remove the two bolts retaining the brake hose bracket and caliper assembly to the spindle. 1 akc care to avoid loosening the bridge bolts that hold the two halves of the caliper to gether. l.ift the caliper assembly off the rotor. 11 SERVICING FORD Caliper Disassembly NOT!" Do not remove the budge bolts that hold the two halves of the caliper together. The caliper is shown separated in l ignic 21 for illustrative purposes only. ]. Remove the two attaching bolts and the caliper splash shield (l ie. 21). 2. If not previously removed, iemovc the two shoe and lining assemblies 3 Remove the flexible biakc hose from the caliper. 4. Remove Ihc external transfer tube. 5. Remove the four dust bools fiom the calipci housings and piston grooves. 6 Clamp the caliper in a vise and sccuic it by the mounting flanges on the inboard housing 7. Remove the four pistons from the cylinder bores with a special tool, such as the one shown in 1'igure 22 To prevent cocking, that may cause damage to the piston or bore, lotatc the piston with the tool while pulling it outwaid Use care to avoid snatching or damaging the outside diameter surface or dust boot retaining groove of the piston. Such damage causes poor sealing. 1'igurc 22- Removing or Installing Piston in /1xed Caliper Cleaning and Inspection Clean all metal parts with isopropyl alcohol or a suitable solvent. Use clean, dry, compressed air to clean out and dry the grooves and passage ways, lie sure the caliper bore and com ponent parts arc completely free of any foicign material Check cylinder bores and pistons for damage or excessive wcai. Replace piston if pitted, scoicd, or the chiomc plating is worn off. Check the caliper dust boot retainer for wear or damage. Caliper Assembly 1. Clamp the mounting flange on the inboard housing in a vise. 2 Apply a film of clean brake fluid to new caliper piston seals and install them in tire grooves of (he cylinder bote. Position the seal at one area in the groove and gently work around the gioove. DO NOT INSTALL USLI) ShAIS. 3. Install new dust boots by setting the flanges squarely in the outer grooves of the caliper bores. 4. Coat outside diameter of pistons with brake fluid and install pistons in cylinder bores so that the open end of piston and the boot retaining groove face out of the bore. To avoid cocking, locate piston squarely in bore and apply a slow even pressure. If a piston will not easily go all the way into the bore, remove it and thoroughly inspect cylinder bore, piston seal, and installation of scat. If the piston still will not go in (with bore in good condition and piston seal propcily in stalled), use the tool shown in Figure 22. Rotate the piston with the tool while pushing inward with a steady force. 5. Carefully install four new dust boots on cahpcr housings and pistons. Be sure each boot fully scats in the gioove of its respective cahpcr housing and piston (l ig. 21) DO NOT INSTALL USFD DUST BOOTS. , V. If a piston is so completely seized in a cylinder bore that it cannot be removed with the special tool, the caliper housing must be replaced. If the caliper dust boot retainer or retaining groove is damaged or scratched, pry the retainer out of the caliper housing with screwdrivers. (Docs not apply to '68 or '69 models.) 8. Remove the rubber piston seals from the grooves in the cylinder bores by carefully inserting the point of a small knife or other pointed instrument under the seal. Raise the seal up far enough to pull it out with the fingers. Lining Installation 1. Position a new shoe and lining assembly on each side of rotor so lining faces rotor. Be sure that the tabs on the shoe flanges fully scat against caliper bridges (1 ig. 19). If cahpcr was not disassembled proceed as follows: 2. Install caliper splash shield and secure to caliper with two retaining bolls. 3. Pump brake pedal several times until a firm pedal is obtained, indicating linings have seated properly. 4. Install wheel and tire assembly on hub and rotor. 5. Check and fill master cylinder reservoir with brake fluid as required. Road test the car. NOTH: It should not be necessary to bleed the system after just a shoe and lining replacement. However, if caliper has been removed and disassembled, continue installation. BRAKE SYSTEMS.. . PART I M Caliper Installation 1. If the caliper assembly has been replaced, transfer the steel tubing and bleeder screw to the new caliper. 2. Install the flexible brake hose to the caliper. 3. Position the caliper assembly on the rotor, and mate the mounting bolt holes in the caliper with those in the spindle. It may be necessary to push the caliper pistons into the cylinder bores to obtain clearance between the shoe and lining assembly and the rotor The shoe and lining assemblies should be seated properly on the bridges. 4. Install the caliper to spindle retaining bolls and torque them to specifications shown in chart on page 11. Cheek to insure the rotor runs squaiely and centrally between the two halves of the caliper. 'J here should be approximately 0.090-0.120inch clearance between the caliper and the rotor outside diameter. 5. Position the steel transfer tube brake hose bracket and caliper assembly to the spindle. Install retaining bolts. 6. Connect front wheel steel transfer tube fiom the caliper to the front brake hose connector. 7. Bleed brake system and ccntrali?c the differential valve Cheek the master cylinder fluid level. Add the correct fluid as required. Pump the brake pedal several times to actuate the piston seals and to position the shoe and lining assemblies. 8. Install wheel and tire assemblies, and road test the car. Floating Caliper Cleaning and Inspection Lining A quick check of floating caliper linings can be made by simply removing the wheel and tire. 1 o make a thorough check, how ever, the caliper must be removed. When removing the caliper, be sure and cap the brake line hose to prevent brake fluid from leaking from the master cylinder. To facilitate removal of shoe and lining assemblies, the piston may have to be pushed into its bore. Apply a steady inward pressure against the inner shoe and lining assembly. Maintain pressure for at least one minute. Slide the two outer shoe re taining clips off the retaining pins (Fig. 9). Remove retaining pins from outer shoe and remove shoe from the caliper. Slide the inner brake shoe outward until it's free of the hold-down springs, then remove shoe. Remove caliper locating pins, stabili7cr attaching bolts, and stabili7cr(s) Remove locating pin insulators from the anchor plate. Discard locating pin insulators and stabili7crs from Falcon, Fairlanc, Mustang, Montego and Cougar, as these parts must be replaced each time brakes arc relincd for these models. On l ord, 1 hunderbird, Continental Mark 111 and Mercury models, the locating pin insulator must be replaced, but the stabilizers being stainless steel, do not re quire replacement unless damaged. Make three thickness measurements with a micrometer across the thinnest section of the shoe and lining. Jf the assembly has worn to a thickness of 0.230-inch (shoe and lining together) or 0.030-inch (lining material only) at any one of the three measur ing locations, or if there is more than 0.125-inch taper from end to end (f ig. 23), or if lining shows evidence of brake fluid con tamination, replace all (4) shoe and lining assemblies on BOTH front wheels The taper wear pattern occurs on floating caliper disc brakes because of the off-center anchor plate abutments Although this causes the caliper to shift within the anchor plate to assume an angular position, the resulting tapered linings have about the same service life as fixed caliper brakes DIRECTION or ROTATION CAl IPIR ANGLE REtATIVE TO ANCHOR PLATE LEFT CALIPER BOTTOM VIEW figure 23-7 aper Wear Paltern Rotor Runout 1 he rotor runout check information on page 11 for fixed caliper brakes also applies to floating caliper brakes, except for the minimum limiting dimensions for resurfacing. All 1968-69 cars with floating caliper brakes require a ball and gauge bar (Rotunda FRF.-70160, or equivalent) to measure wear on the rotor inner braking surface, and to determine the maximum stock removal limit during refmishing. Gauge the rotor on the bench prior to mounting it in a rotor lathe. 13 Comrollcd dimension notches arc machined in the opposite edges of the gauge hat (1 lg. 24) and identified Custom Car (F ord. Mercury, Continental Mark III and 1 Jiundcrbird) and 1 iglu Car (Montego, I airlanc, 1 alcon, Mustang and Cougar). Brake Hoses Cheek for signs of cracking, leaks or abrasions. Replace as required Removal, Overhaul and Installation Caliper Removal Remove the wheel and tire assembly from the hub and lotoi Use care to avoid damage or interference with the caliper splash shield or bleeder screw fitting Disconnect the biakc hose from the caliper and cap to prevent loss of fluid from the master cylinder Remove the spindle attaching bolts and lift the caliper assembly from rotor. I igure 24- Hooting Caliper Roloi Refnislung /.muling Dimensions The rotor is gauged as follows: 1. Remove inner beating assembly and grease retainer. 1 horoughly clean inner beating cup and hub bore 2. Carefully place the gauge ball in the inner bearing cup (DO NOT DROI*). 3. Position gauge bar acioss the rotor inner braking surface and over the gauge ball (1 ig, 24). Measure the distance between the gauge bar and ball. 11ns equals the maMmum amount of stock that can be removed. If the gauge bar touches the ball, no additional stock may be icmovcd. If (he gauge bar is below the top of the ball, replace the rotor. 4. Minimum rotor thickness dimensions arc shown at both ends of the rotor in 1 igure 24 Rotors having a thickness less than these specifications must be replaced, icgaidlcss of the ball and gauge bar mcasuicmcnts. Caliper 1 he cleaning and inspection information for fixed caliper brakes also applies to floating caliper brakes except for the caliper to spindle bolt torque specifications , The following chart lists torques for 1968-69 cars. FLOATING CALIPER TO SPINDLE ATTACHING BOLT SPECIFICATIONS Upper bolt Lower bolt- Ford, Mercury, 1 hunderbud, Continental Mark III Lower bolt- Montego, falcon, Fairlane, Cougar, Mustang 110 140 ft lbs 90 1?0 ft lbs. 55-75 ft. lbs. Caliper Disassembly Disassemble the caliper as described under "Innings"- "Clean ing and Inspection" on page 13 This will remove all pails except the piston T o remove piston, apply air pressure to the fluid port m the caliper with a rubber tip noz/lc as shown m I igure 25 Place a cloth over the piston before applying air picssuic to pic\cnt damage to piston and spraying brake fluid If the piston is seized and cannot be forced from caliper, tap lightly around the piston while applying an pressure. Cate should be taken bceatise the piston can develop considciabtc force due to picssuic build-up Remove the dust boot from the caliper, then the rubber piston seal from the cylinder and discard. --. i. ' / tgurc 25- Using Air Pressure to Remove Piston Cleaning and Inspection The same information under "Cleaning and Inspection" for fixed caliper biakcs, page 12, also applies to floating caliper brakes. Caliper Assembly Apply a film of clean brake fluid to a new caliper piston seal and install in cylinder bore. Fie sure seal docs not become twisted and that it scats fully in its groove Install a new dust boot by setting the flange squarely in outer groove of caliper bore. Coat piston with brake fluid and install in cylinder bore Spread dust boot over piston as it's installed. Scat dust boot in piston groove. 14 BRAKE SYSTEMS.. . PART I Lining Installation When installing new shoes and linings, it is necessary to force the piston to the bottom of its bore. Apply sufficient pressure to overcome the grip of the piston seal on piston. Install new caliper locating pin insulators in anchor plate. Position caliper assembly in anchoi plate. Position new stabilizer or stabilisers (all 1 alcon, 1 airlanc, Mustang, Montego and Cougar- if required on 1 ord. Mercury, '1 lumdcrbird and Continental Mark 1)1) and install caliper locating pins to engage approxi mately four tlueads If the caliper locating pins arc rusted oi corroded, they should be icplaeed. Apply isopropyl alcohol to caliper locating pins befoic installation. After assembly the alcohol will evaporate and permit the pins to operate in a "dry" condition. Neva use oil, grease or similar lubes. Position outci biahc shoe on caliper and install the two retain ing pins and clips Install the inner brake shoe so that cars of shoe are on top of anchoi plate bosses and under shoe hold down springs. Position the shoe and linings assemblies so the .caliper assembly can be placed over the ictor Rotate a hammer handle between the linings to icsct the stabilizers. Metering Valve 1 incoln Continental and F-250 & 350 Truck models only use a metering valve in the front hydraulic system with disc brakes. It is serviced as an assembly and is never adjusted or overhauled. During bleeding operations, a release rod at the bottom of the metering valve must be held open at least Mo inch Centralizing Differential Valve of Dual Brake Systems Caliper Installation Install the caliper assembly over the rotor and on the spindle. It may be necessary to push the caliper piston into the cylinder to obtain clearance between rotor and lining assembly. Install the two caliper attaching bolts, and torque to the specifications in the chart on page 14. _, 7he upper boll must be tightened first as shown in Figure 26. Install the safety wire and twist the ends at least five turns Push the ends against spindle to avoid interference with brake hose and steering slop Install a new copper washer on each side of the brake hose fitting, and attach to caliper. lilccd the brake system and centralize the differential valve. Cheek master cylinder reservoir fluid level. Add specified brake fluid as required. Pump brake pedal several times to actuate the piston seals and to position the shoe and lining assemblies, install wheel and tire assembly and road test the car. INStAll BOH! CAUPIR Alt ACHING BOltS f INCfft-TICHl, 1 lit N TIGHT fN THIS BOLT TO SPECIF ICAIIONS t |R$T After dual brake system (1 ig. 27) has been repaired and bled, the warning light on the instrument panel will usually continue to glow because the pressure differential valve is in the off-center position. To centralize the pressure differential valve and turn off the warning light, a pressure differential or unbalance con dition must be created in the opposite brake system from the one that was last repaired or bled. Turn ignition switch to ACC or ON position l.oosen the differential valve assembly brake tube nut at the outlet port on the opposite side of the brake system that was last repaired or bled. Depress brake pedal slowly to build line pressure until the pressure differential valve moves to a centralized position and the brake warning light goes out; then, immediately tighten the outlet port tube nut. Check fluid level in master cylinder reservoirs, and fill to */i-inch from the top with specified brake fluid, if necessary Turn ignition switch OIT. Rcforc driving the vehicle, check operation of brakes and be sure that a firm pedal is obtained J'lgurc 26- Caliper Attaching Holt lightening Procedure SERVICE PROCEDURES-Hydraulic System All disc brake systems use a proportioning valve between the pressure differential valve and the rear brake wheel cylinders The proportioning valve is serviced as an assembly and is never adjusted or overhauled. Brake Fluid Specifications l ord llrakc Muid -- Lxtra Heavy Duty (Part N0..C6AZJ9542-A) (Spec. I SA-M6C25-A) or equivalent, is mandatory for all disc brake applications, and recommended for drum brakes. NOT!': All 1968-69 cars are filled with extra heavy duty brake fluid at the factory, lixtra heavy duty brake fluid is colored "blue" for identification purposes. Do not mix low temperature brake fluids with it. f ord Brake Muid--Super Heavy Duty (Part No. B7A7.19542-A) (Spec. SAP. J1703), or equivalent, can be used for cars with complete drum brake systems only. DON'f MISS . .. SERVICING FORD BRAKE SYSTEMS- PART II in February Shop Tips- Covering Adjustments, Bleeding, Parking Brake, Master Cylinder and Power Booster. PLUS... Cortina Brake Service. 15 CENTRAL MOTORS FORD INC. 1900 S. FIGUEROA 748-2367 LOS ANGELES, CALIFORNIA 90007 YOUR SOURCE FOR GENUINE FORD AND AUTOLITE ORIGINAL EQUIPMENT PARTS BOTH Brand-New and Ford Authorized Remanulactured Brake Linings Provide original Equipment Quality Meet all state and federal brake regulations. Quality control tested . Precision pre-ground for smooth, even linlng-to-drum contact. / -1' '' Scientifically-selected lining , material more effectively dis sipates heat, to resist brake fado and provide longer wear. And to keep all Ford Quality in Ford brakes... install Ford wheel cylinder Repair Kits SAME high quality as original equipment cups and boots. ' . ' t] ' All-rubber compound is high temperature, wear resistant type. .* >/v ` Precision molded boots fit tight... to seal hydraulic system from dirt and moisture., ' Cups designed to 'maintain full, continuous sealing for smoother, surer braking. * .