Document MojZV274zyKxY1KwJQ7ZR2Rok

; _ -o 31 12103 DECEMBER 18. 1975 r BULLETIN Vo. qioii under brakes OR BRANCHES AND DISTRIBUTORS ONLY. / CHASSIS AFFECTED ALLENTOWN2j HAYWARDD OAKVILLED MANDATORY SAFETY CAMPAIGN REF: SC067 BRAKE TREADLE VALVE PIPING (R. RD. RM. U. DM. DMM. F and MB with MVSS121 Dual Brake System) PURPOSE To advise of possibility that some chassis may have the primary and secondary supply line connections reversed at the brake treadle valve or air junction block. In the event of air loss in either primary or secondary system the service brakes would not function on these chassis. RECOMMENDATION Inspect all affected chassis as outlined in bulletin and correct treadle valve piping if required. Complete the campaign as quicklv as possible to assure safe operation of these vehicles and comply with Federal safety regulations. INFORMATION Reversed supply piping at the treadle valve will not affect braking if both primary and secondary reservoirs are charged: however it will render both primary and secondary service brake systems inoperative if air pressure is lost in either supply system. Should this occur, the spring brakes must be applied manually to stop the vehicle. Approximately 1200 vehicles built between September 2. 1974 and March 31. 1975 may have this condition. Branches and distributors will be supplied with a list of affected chassis that will include known owners names. Procedure: 1. Drain the secondary reservoir. Disconnect control line at steering axle brake controller. Make a treadle valve application and check for air at the disconnected line. If air is discharged, the treadle valve is piped wrong. NOTE The secondary reservoir can be identified by following features. (a) On most combination reservoirs, there is plate show ing which is primary and secondary section. (b) On combination reservoirs without identification plates, locate secondary section as follows. Start at steering axle brake controller and trace the 5 8 inch supply line to the secondary reservoir. (c) If separate reservoirs are used the secondary is the smaller one: however do not confuse it with supply (wet) tank. CIRCULATION Service Manager Shop Foreman Night Foreman Night Foreman Inspector Leadman Inspector Leadman Inspector Leadman Unit Over haul Room. Shop Office (Continued Over) Service Operations. Allentown. Pa.. U.S.A. Afackz P fh N ItU IN BULLETIN JANUARY 12. 1976 under\. qioio brakes for branches and distributors only. (Supersedes Bulletin aated DECEMBER 17, 1975) / CHASSIS AFFECTED ALLENTOWNQf HAYWARDO OAKVILLEE3 MANDATORY SAFETY CAMPAIGN REF: SC066 BRAKE ANTI-WHEEL LOCK WIRING (R. RO. U and DM with MVSS121 Anti-Lock System) PURPOSE To advise of the requirement for inspection and possible correction of front axle brake controller wiring connections. If the controller is connected incorrectly, the front brakes could lock during a panic stop. RECOMMENDATION Check front axle brake controller connections on all affected chassis and correct as required. Complete the campaign as soon as possible to insure safe oper ation of these vehicles and compliance with Federal safety requlations. INFORMATION On some vehicles, the wires from cab power/warning harness to front axle controller were connected to one of the controller wheel sensor leads instead of the controller power''warning leads. When connected in this manner, the controller is not powered, resulting in loss of anti-wheel lock capability on the front brakes and failure of the warning light to indicate this malfunction. Under this condition, the front brakes operate in the fail-safe mode, but without anti lock control and therefore could lock during a panic stop. Approximately 3400 chassis built from September 1974 through July 17, 1975 could have this condition. A list of these vehicles will be supplied to all affected branches and distributors. Procedure: Check wiring color coding at the harness connections at front axle con CIRCULATION troller. If they are as shown in Figure 1. no further inspection or cor Service rection is required. Manager Shop HARNESS FROM WARNING UNIT IN CAS Foreman Might Foreman Night Foreman Inspector Leadman Inspector Leadman Inspector Leadman Unit Over haul Room | HARNESS CONNECTIONS AT BRAKE CONTROLLER CORRECT (Continued Over) Service Operations. Allentown. Pa.. U.S.A. Shop Office Mack SERVICE BULLETIN FEBRUARY 16. 1976 \o . Q1012 under brakes FOR HRANCHES AND DISTRIBUTORS ONLY CHASSIS AFFECTED ALLENTOWN0 HAYWARD OAKVILLE d MANDATORY SAFETY CAMPAIGN REF: SC058 TRACTOR TRAILER PARK VALVE PIPING (F Models with MVSS121 Brake System) PURPOSE To inform the field of possibility that some park valves were piped incorrect iv. causing an automatic spring brake application in the event of air loss in primary system. When this occurs it is necessary to release the spring brakes manually. RECOMMENDATION Complete the campaign as quickly as possible to insure safe oper ation of these vehicles and compliance with Federal safety regulations. INFORMATION On current F model chassis there are two brake svstem air maniioids located inside the console, above the engine compartment. The forward manifold has a line connected to the double check valve lo cated on right hand frame rail near the air reservoir (see Figure 1) and the rear manifold has a line connected to the treadle valve. On some chassis, these lines were interchanged at the manifolds, resulting in the primary air system becoming the sole source of air to the park valve. When piped this way, loss of primary air will cause automatic application of the spring brakes and. because there is no secondary air available, the brakes must be released manually. Total of 596 chassis, built between September 2. 1974 and July 30. 1975 may have this condition. A list of these chassis will be supplied to all affected branches and distributors. Procedure: To check for subject condition, proceed as follows: ]. Chock wheels so truck will not roll, then release parkin*, brake. 2. With both primary and secondary reservoirs fully charged, drain primary reservoir. 3. While primary tank is draining, observe rear brakes and note whether or not spring brakes apply. a. If spring brakes do not apply, after primary reservoir is fully drained, system is piped correctly and no further inspection or correction is necessary. b. If spring brakes apply, system is piped incorrectly and must be corrected according to instructions in following steps. NOTE The primary reservoir can be recognized by the following features: a. Identification plate stating "PRIMARY" if combination tank. b. If plate is missing, determine which end of tank is connected to the rear axle brake controller(s). This will be the pri mary reservoir. c. If vehicle has two reservoirs, the primary reservoir is the larger of the two. circulat: Service Manager Shoo F ore.man Night Foreman Nigr.c Foreman inscscior Lea dr*.an Inspector Lea dm an Inspector Leadman Unit Over haul P.ocm Shcp Office (Continued Over > Service Operations. Allentown. Pa.. U.S.A. Mack RVIC APRIL a, 1976 \o. Q1013 under BRAKES -OR BRANCHES AND DISTRIBUTORS ONl_v CHASSIS AFFECTED ALLENTOWN HAYWARD Ef OAKVILLE i_ MANDATORY SAFETY CAMPAIGN SC072 FRONT 7.'HE EL SPEED SENSOR ROTOR (Mack Western Models RL, RS.WL and WS with Anti-wheel Lock System) PUR POSE To notify the field that the front wheel rotors must be replaced on certain of these vehicles. Some rotors have been damaged by internal interference, thereby causing malfunction or failure of the front axle anti-wheel lock system. RECOMMENDATION Replace front wheel rotors on all chassis involved and replace pickups as required. Complete the campaign as quickly as possible to insure safe operation of these vehicles. Parts will be available approximately April 26. 1976. ENFORMATION Vehicles subject to this condition are those equipped with Rockwell International FF-931 and FL-931W front axles having aluminum hubs for 10 hole disc type wheels and Eaton anti-wheel lock system. Wheel speed rotors used on these chassis may be incorrect. The incorrect rotors extend out too far from the brake drum and create a potential interference condition with the sensor pickup. Damage to these parts will occur if the pickup lacks adequate adjustment range to compensate for the oversize rotor. If interference occurs, malfunctions ranging from a temporary dis abling to a complete failure of the front axle anti-lock may result, depending on degree of interference. Failure of both sensors will result in loss of anti-wheel lock capability but the warning light will not be activated. Approximately 350 vehicles ouilt between March 13. 1975 and Dec ember 11. 1975 are involved in this campaign. A list of these vehicles will be supplied to all affected branches and distributors. Parts CIRCULATION Service Manager shop Foreman istgnc Foreman N'ignt Foreman Inspector Leadman inspector Leadman Inspector 1 Leadman I Unit Over haul Room Two front wheel rotors are required for each vehicle campaigned. In addition, if a pickup is damaged it must be replaced also. Order parts on an emergency requisition. Include only parts required for the campaign on this requisition.* Shop Office Parts required: Qty. 2 * * Part Number Description 12MN39302A-P1 Wheel Speed Sensor Rotor 8MNA41-P15 Wheel Speed Sensor and Brkt. Ass'y. (FF-931) 8MNA39301 -PI Wheei Speed Sensor and Brkt. Ass'y. (FL-931W) v n<; ni oiinin * Order only if original parts are damaged. (Continued Over) Service Operations. Allentown. PA.. U.S.A. Mack No. Q1Q13 under BRAKES (Sheet =2) 3. Loosen screw packs and slide pickup to it's maximum outboard position on mounting bracket. Retighten screw packs 40 to 45 in. lbs. This applies to both new and used assemblies and is necessary to assure that the correct operating clearance will be established with the new rotor. 4. Connect pickup leads (if new pickup was installed) and install wheel and drum assembly. NOTE Rotor-to-pickup operating clearance is established auto matically when the wheel is installed. Avoid "rocking" the wheel as it approaches the installed position as this can push the pickup too far inboard and adversely affect the sensor signal. Use the bearing adjusting nut to draw the wheel into position. Reimbursement All expenses incurred in this campaign are to be recovered through RWR procedures as instructed in Service Bulletin AJ1G00 under POLICY. The usual $25. 00 minimum for claims is waived and an RWR must be submit ted for each chassis campaigned. Include following information on the RWR form. Under Enter Description of failure - - - - Service Bulletin QI013 under BRAKES Failed Part Number------------ SC072 Part Name--------------------------- Rotor Maximum labor allowance is 1. 5 hours per chassis. Removed parts - Hold removed parts, pending instructions for return. RV ^ 3* f * X-Sfc JULY 28, 1976 ?< ' 4 s & i *3 j ^0* au)H UlldCF BRAKES FOR BRANCHES ANO DISTRIBUTORS ONLY CHASSIS AFFECTED ALLENTOWNiZ HAYWARDS''OAKVILLEZ MANDATORY SAFETY CAMPAIGN REF: SC076 FRONT BRAKE CHAMBER RELOCATION (WL and WS with FAW536C, 537C Front Axles and Cam Brakes! PURPOSE To notify the field that the brake chamber mounting arrangement on subject chassis equipped with FAW536C and 537C must be cnanged to eliminate possible interference between brake chamoer and cab tilt cylinder. This interierence could cause chamber damage with potential reduction in braking ability. RECOMMENDATION Relocate brake chambers on all affected chassis as instructed herein. Complete the campaign as quickly as possible to insure safe operation of these vehicles. M IN U U IN U S A INFORMATION The brake chamber /tilt cylinder interference occurs under extreme front axle articulation. To provide greater clearance at this point, the brake chambers must be repositioned to the rear oy use of a new mounting brocket. See Figure 1. Approximately 400 vehicles built between December 16, 1974 and September 9. 1975 may nave this condition. A list or these vehicles is provided :n this bulletin and will also oe included in the camoaien package supplied to all affected Brancnes and Distributors. Parts Order parts on an emergency requisition from the parts distribution center normally serving your location. Include only parts required for the campaign. State on the requisition tiiat the parts are for a mandatory safety campaign per Service Bulletin Q1Q14 under BRAKES. Quantity Part Number 1 823 5-F3 3299 -R15 52 1 1 8235-F33299-S1553 2 8MY130 2 1 73RU22022 ' Description j Brake Chamber Brkt. and Bush. Assy., L.H.J Brake Chamber Brkt. and Bus.n. Assy., R.H.I Brake Chamber Ecot i Boot Retainer Plate 1i CIRCULATION Service Manager Shop Foremaui Nignt Foreman Night Foreman Inspector Leadman Inspector j Leadman , Inspector Leadman Unit Over haul Room ; Shop Office j j (Continued Overt Service-'Operations. Allentown, Pa., U.S.A. Mack _ No. Q1014 under BRAKES (Sheet #2) 8. Install brake chamber on bracket. 9. Loosen brake chamber clamp and rotate cover until side port is at twelve o'clock (top) position, then tighten clamp. See Figure 1. 10. Install the elbow in side port of the brake chamber and plug the center port. Position elbow so it points towards front of chassis. See Figure 1. 11. Reinstall brake chamber air hoses. Existing hoses can be reused if at least 18" long after positioning elbow port per Step 10. 12. Adjust slack adjusters. Reimbursement All expenses incurred in this campaign are to be recovered through RWR procedures as instructed in Service Bulletin AJ1000 under POLICY. The usual $25.00 minimum for claims is waived and an RWR must be submitted for each vehicle campaigned. Show the following information on the RWR form. Under Enter Description of Failure-------------Service Bulletin Q1014 under BRAKES Failed Part Number----------------SC076 Part Name------------------------------ Brake Chamber Maximum labor allowance -- 2.5 hours per chassis Removed parts -- Hold until advised of disposition. (Continued Over) BULLETIN APRIL 13, 1978 \0. Q1015 under brakes for branches and distributors only. (Supersedes Bulletin dated AUGUST 18, 1977) CHASSIS AFFECTED ALLENTOWNG HAYWARDgf OAKVILLEG MANDATORY SAFETY CAMPAIGN REF: SCO84 FRONT BRAKE ASSEMBLY (Mack Western Models WL and WS With Rockwell International FF931C Front Axle and "p" Series Cam Brakes) PURPOSE To request the inspection and possible modification or replacement of subject brake assemblies to overcome failure of the brake spider. Failure of a spider results in brake pull to the direction opposite the broken spider or wheel lock-up on the wheel with the broken spider, resulting in impaired vehicle control. INFORMATION AND RECOMMENDATION It has been determined that Rockwell "P" cam brake assemblies, when assembled with brake cam rotation opposite wheel ro tation (rotation being defined when the chassis is going forward),are subject to a ''chatter" condition that could lead to failure of the brake spider. On vehicles with manual steering the brake assemblies must be checked and if found to have camshaft in opposite rotation they must be removed and reassembled so cam and wheel rota tion is same, after Magnafluxing the spiders for cracks. On vehicles with power steering, an interference condition exists such that the pre sent "P" cam brake assembly cannot be used with the brake assembled for cam rota tion same as wheel. On these chassis it will be necessary to install alternate assem blies, either the Rockwell 'T" series cam brake or Rockwell wedge brake. The brake to be used depends on chassis application as described later in this bulletin. CIRCULATION Service Approximately 570 vehicles built between January 6, 1975 and December 10, 1976 are Manaaer involved. A list of these vehicles will be sent to the affected branches and distributor: Shop Procedure Foreman Night There are three chassis configurations involved and the corrective action varies for each. The differences are in steering type, i.e. manual or power, and rear axle configuration and are as follows: Foreman Night Foreman Inspector NOTE Leadman inspector The following instructions must be strictly adhered to to assure complicance with current requirements of Federal Motor Vehicle Safety Standard 121. If not followed, you could be subject to fine. Leadman Inspector Leadman Unit Over All with manual steering (Refer to item 1). haul Room Tandem tractors with power steering (Refer to item 2). Single axle tractors and truck-trailers with power steering (Refer to item 3). (Continued Over) Service Operations, Allentown, Pa.. U.S.A. Shop Office Mack APRIL 13, 1978 No. QI015 under BRAKES (Sheet 2) c. Transfer spiders, camshafts and brake chambers to the side opposite the one they were originally installed on. Be sure cam and chamber are oriented as shown in Figure 3. Complete the assembly using a new inner wheel seal. Torque brake assembly mounting bolts 268 to 296 lb. ft. Torque spoke wheel clamp stud nuts 122 to 135 lb. ft. Torque disc wheel stud nuts 450 to 500 lb. ft. NOTE Do not transfer brake drums and shoes. These parts must remain on same side as originally installed and shoes must also be installed in same position, (i.e. primary & secondary). 1. BRAKE CHAMBER 2. BRAKE ASSEMBLY, 16-1/2 X S CAM (L.H. SHOWN) 3. BRAKE CAMSHAFT FIGURE 3 d. After installing the wheel assembly and adjusting the wheel bearing, check for correct operation of anti-wheel lock system as follows. Spin wheel at approximately five mph. (40 rpm) and check voltage at sensor lead; it should be 0.3 to 0. 5 volt AC. If less, readjust sensor to rotor clearance. e. Burnish brake linings using following procedure. Brake vehicle from 40 mph to 20 mph. a minimum of 20 times. Allow one half mile between brake applications to prevent overheating the brakes. Readjust brakes when burnishing operation is com pleted. (Continued Over) APRIL 13, 1973 No. -iLG15 *r.aer d RAKES (Sheet 3) c. Install quick release valve 20QE291 on encir.e front support in same location from which the front wheel controller was removed. Mount on bracket shown in parts list using existing fasteners for rhe bracket new fasteners for the valve. This valve is required to perform me quick r.uease junction formerly provided by the front axle controller. Pipe the valve as shown in Figure 6. Remove line originally used to connect con troller supply port to secondary reservoir and plug tank opening. This line is not required. FIGURE 6 d. Install a jumper between the front axle terminal and W2 terminal of the failure warning unit located in cab. This step is necessary with removal of the front axle controller, to prevent a false failure indication. See Figure 7. 3. BOGIE REAR AXLE 8. BOGIE REAR AXLE FIGURE 7 (Continued Over) APRIL 13, 1978 No. Q1015 under BRAKES (Supersedes Sheet dated AUGUST 18, 1977)(Sheet 4) List B - Parts required for tandem tractors equipped with disc wheels and power steering Part Number 1QDA49357R Brake Assembly, R.H. (15 x 4 cam) i . 1QDA49358R 2 17QJ39337 1 5QJA39344 1 5QJA39345 10 9872-84527 10 9872-84528 1 5QJA39340 1 5QJA39341 Brake Assembly, L.H. (15 x 4 cam) Brake Drum Hub Assembly, R. H. Hub Assembly, L. H. Wheel Stud, R. H. Wheel Stud, L. H. Drum & Hub Assembly, R.H. Drum & Hub Assembly, L.H. 2 7843-3434095 Hub Cap 2 121SR19 Hub Cap Gasket 14 3AX1809 Bolt, Brake Mounting, 5/8-18 x 2 2 341SR52 Seal, Wheel Inner 1 20QE291 Quick Release Valve 1 29QE39304-P2 Quick Release Valve Bracket (excepfwith Cummins 1 29QE39304-P1 Quick Release Valve Bracket (with Cummins) 2 LAX 13 Bolt, Quick Release Valve Mntg. 4 37AX38 Washer, Quick Release Valve Mntg. 2 21AX783 Lock Nut, Quick Release Valve Mntg. 2 8235-A22-3275- G-501 Slack Adjuster ist C - Parts required for tandem tractors equipped with SDOke wheels and Dower st Quantity Part Number Description 1 1QDA49357A Brake Assembly, R.H. (15 x 4 cam) 1 1QDA49358R 2 17QJ39336 Brake Assembly, L.H. (15 x 4 cam) Brake Drum 14 3AX1809 Bolt, Brake Mounting, 5/8-18 x 2 2 341SR52 Seal, Wheel Inner 1 20QE291 Quick Release Valve 1 29QE39304-P2 Quick Release Valve Bracket (excep w/fcummins) 1 29QE39304-P1 Quick Release Valve Bracket (with Cummins) 2 LAX 13 Bolt, Quick Release Valve Mntg 4 37AX38 Washer, Quick Release Valve Mntg. 2 21AX783 Lock Nut, Quick Release Valve Mntg. 2 8235-A22-3275- G-501 Slack Adjuster List D - Parts required for trucks and-4 x 2 tractors with disc wheels and power steering Quantity Part Number Description -------- 1----- 1QDA493^3R-Pl Brake Assembly, R.H. (15 x 5 Wedge) 1 1QDA49354R-P3 Brake Assembly, L.H. (15 x 5 Wedge) 2 17QJ39310 Brake Drum 2 341SR52 Seal, Wheel Inner 2 63AX69 * 144SX22FT25 Tee Fitting Hose 2 92RU19317-P3 Hose Fitting 2 92RU19313-P4 Hose Fitting 50 inches required per vehicle (Continued Over) BULLETIN JULY 20, 1978 \0. Q1017 under brakes FOR BRANCHES AND DISTRIBUTORS ONLY. CHASSIS AFFECTED ALLENTOWNC HAYWARD0' OAKVILLEC P filN H D IN U iA MANDATORY SAFETY CAMPAIGN REF: SC099 AIR DRYER PIPING (Mack Western Models RL,RS,WLand WS With Anchorlok Air Dryer) PURPOSE To notify the field of need to revise the air dryer piping on subject models to prevent possibility of moisture freezing in the relief valve or air compressor governor control line. Should this condition occur, air system damage may result that will cause automatic aoplication of the sprin brakes and possible loss of vehicle control. INFORMATION AND RECOMMENDATION The original piping for Anchorlok air dryers has low points that permit any moisture which passes through the dryer to collect in relief valve and compressor governor control line. If this moisture freezes it will, in some cases, cause excessive brake system pressure. This high pressure can cause failure of brake system hoses and valves which, in turn, causes automatic application of the spring brakes. These events can occur with out prior warning to the operator. Approximately 400 vehicles, built from December 1975 through January 1978, re quire modification to the air dryer piping. A list of these vehicles will be supplied to the affected branches and distributors. Procedure Basically, the piping revision consists of relocating the relief valve and gover nor control line to eliminate low points. To accomodate this change it is neces sary to relocate the primary reservoir line and, if used, the air starter line. Figure 1 shows piping as originally installed. This arrangement must be re vised. Figure 2 show's piping arrangement that must be followed for this campaign. CIRCULATION Service Manager Shop Foreman Night Foreman Night Foreman Inspector Leadman Inspector Leadman Inspector Leadman Unit Over haul Room (Continued Over) Service Operations, Allentown, Pa., U.S.A. Shop Office BULLETIN AUGUST 16, 1978 \0. Q1019 under brakes FOR BRANCHES AND DISTRIBUTORS ONLY. CHASSIS AFFECTED ALLENTOWNf HAYWARD5Z OAKVILLE^ MANDATORY SAFETY CAMPAIGN REF: SC 100 ANTI-WHEEL LOCK CONTROLLER (Models R,RD, U, DM,DMM,DML, F,MB,HMM,RM RL, RS, WL and WS With Eaton Anti-Wheel Lock System) PURPOSE To notify the field of need to recall certain of these vehicles to inspect and where necessary replace the controller. An electrical malfunction in these controllers can cause a "no brake condition" on the axle being controlled by the affected anti-wheel lock controller. INFORMATION AND RECOMMENDATION The Eaton Corporation has informed Mack Trucks, Inc. that some controllers manufactured prior to March, 1976 may not be to specifications. This coupled with the failure of certain other electronic devices within the controller can cause the valve solenoid to be constantly energized. A constantly energized solenoid will prevent application of brakes on the axle moni tored by that controller. No other axle will be affected. Due to the nature of this malfunction, the warning light is not always activated and, therefore, the driver may not be aware of the condition. Chassis manufactured between October 1974 and March 1976 (May 1976 for Hayward chassis) will be recalled for the inspection and possible replacement of controllers. A list of the chassis involved will be sent to affected branches and distributors. Procedure Corrective action consists of replacing certain Model 21 controllers with con trollers of current production design (Model EAL1201N). Controllers that must be replaced can be identified by the manufacturing date code. The date code has a series of characters. On suspect controllers the third from last is "M" and the last two digits are 26 or lower. Controllers with a date code in this range must be replaced. Example: P2 02775 M14 P2 360 75 M26 P2 310 76 M27 P2 099 75 S10 - Replacement required Replacement required OK - No Replacement required OK - No Replacement required circulation Service Manager Shop Foraman Night Foreman Night Foreman Inapector laadman Inapector Laadman Inapector Laadman Unit Over haul Room (Continued Over) Service Operations. Allentown, Pa., U.S.A. Shop Olllce AUGUST 16, 1978 No. Q1019 under BRAKES (Sheet 2) Parts 4. CONTROLLER 9. POWER LEAD RED 5. VALVE FIGURE 2 MODEL 1200 CONTROLLER/VALVE ASSEMBLY Order parts on an emergency requisition from the parts distribution center normally serving your area. State on the requisition that the parts are for a mandatory safety campaign per Service Bulletin Q1019 under BRAKES. Do not include parts not re quired for the campaign on this requisition. Parts required: Qty. Part Number AR 2719-646048 AR 2719-640049 Description Anti-Wheel Lock Controller, Pos. Grd. Anti-Wheel Lock Controller, Neg. Grd. Reimbursement All expenses incurred in this campaign are to be recovered through RWR procedures as instructed in Service Bulletin AJ1000 under POLICY. Submit an RWR for each vehicle campaigned. Show following information on RWR form. Description of Failure-------------------- Service Bulletin Q1019 under BRAKES Failed Part Number----------------------- SC 100 Part Name.............. .........................--Controller Maximum Labor Allowance: Inspection------------------------------------------- . 3 hr. Replacement (per controller)--------------- . 3 hr. RWR must include - Completed Campaign Questionnaire Return parts carrier name and shipper's Bill of Laden number (Continued Over) CAMPAIGN QUESTIONNAIRE Complete one for eacft controller replaced w/duplicate (cut in half and use carbon). Attach original to RWH and duplicate to be used as packing slip for removed controller. If no controller replacement 13 required, complete oolr ONE copy and attach to RWH. Branch/Distributor Name Location Repair Order Number____________________________________ Date Chassis Model & Serial Number (VIN)_____________________ Mileage_ Controller Identification No. (removed controller) Removed from: (Circle one) Steering Axle Bogie Front Axle Bogie Rear Axle Other___________ Was Anti-Wheel Lock Warning Light Operative - (1) As Received (2) After Controller Replacement (if required) (3) As Released to Customer Yes No Yes No Yes No If Anti-Wheel lock system inoperative after controller campaign inspection and/or replacement (as required), show name of individual (customer or customer representative) whom you notified that system was inoperative and that additional repairs were required. THIS COPY MUST ACCOMPANY RWR (cut here) Branch/Distributor Name Location Repair Order Number,____________________________________ Date Chassis Model & Serial Number (VTN)_____________________ Mileage Controller Identification No. (removed controller) Removed from: (Circle one) Steering Axle Bogie Front Axle Bogie Rear Axle Other Was Anti-Wheel Lock Warning Light Operative - (1) As Received _________ Yes No (2) After Controller Replacement (if required) Yes No (3) As Released to Customer _________ Yes No If Anti-Wheel lock system inoperative after controller campaign inspection and/or replacement (as required), show name of individual (customer or customer representative) whom you notified that system was inoperative and that additional repairs were required ___________________ THIS COPY TO BE USED AS PACKING SLIP BULLETIN OCTOBER 30. 1973 i\o. Q1020 under brakes FOR BRANCHES AND DISTRIBUTORS ONLY. CHASSIS AFFECTED ALLENTOWN0' HAYWARDS' OAKVILLEvf P B lN ltO IN U Ai MANDATORY SAFETY CAMPAIGN REF: SC106 BOGIE ANTI-WHEEL LOCK SYSTEM (F, R. U, DM, DMM. RM, MB, MR, MC, RD, WL. WS, RL, RS, RWL and RWS Having a Single Bogie Controller) PURPOSE To notify the field that the electrical portion of this system must be dis connected to prevent a possible "no brake" condition. INFORMATION AND RECOMMENDATION The vehicles involved in this recall may experience a delay of up to two seconds from the time the brake treadle is actuated until the bogie brakes apply. This condition is caused by defects in the wheel speed sensor wiring. The increased braking time occurs without prior warning to the driver and could result in an accident. This "no brake" condition can occur in vehicles built between October, 1977, and September. 1978, and is restricted to vehicles which have one anti-wheel lock controller to monitor both bogie axles. Branches and distributors will be notified of the vehicles affected. Procedure As a temporary measure, the electrical portion of the bogie anti-wheel lock system must be disconnected. This procedure will remove all anti-lock capabilities of the bogie brakes and they will function as normal pre-FMVSS-121brakes. Drivers must be advised that the bogie wheels can now be locked up and greater care must be exercised when operating on slippery roads to avoid skidding. 1. Disconnect the anti-wheel lock system power lead at the circuit breaker. Tape wire back. Location of the circuit breaker strip and means of identifying the affected wire is shown in the following chart. Page 1 Service Operations, Allentown. Pa., U.S.A. CIRCULATION Service Manager Shop Foreman Night Foreman Night Foreman Inspector Leadman Inspector Leadman Inspector Leadman Unit Over haul Room Shop Office OCTOBER 30, 1978 NOTICE The Wheel Anti-Lock System on this Vehicle has been made Inoperative by Disconnecting the Power Supply. The Brakes are Fully Driver Controlled. 4 MR 1452 Reimbursement Submit an RWR to recover expenses incurred in disconnecting die bogie anti-wheel lock system. Follow procedures given m Service Bulletin A.J1000 under POLICY. The standard $25.00 minimum for claims is waived and an RWR is co be submitted for each vehicle campaigned. Show the following information on RWR form. Under Enter Description of Failure....................................... Service Bulletin Q1Q2Q Failed Part Number............................................ SC 106 Part Name ............................................................. Controller Maximum Labor Time -- 0.3 hour per vehicle END Page 3 Q1020 ftVIC BULLETIN DECEMBER 21, 1978 \o. 01021 under brakes FOR BRANCHES ANO DISTRIBUTORS ONLY / CHASSIS AFFECTED ALLENTOWN0 HAYWARDG OAKVILLEIZ A* -- "//-- * /2i C&_ r/l ./// . Aw-t A. '-"i'fc /?*'c J. 4LL. A/LAr r--/L C * t* / ' A ' ' /aj A^/^&c^Zrrjy ~ S*- ~ - / Lf'i7~ ^ JJ~7~4cr'1 //// T*; ,, Y ^ 7~-v>r C at .J , U,t}- rA^7" 5u#U<r' -,.U> MANDATORY SAFETY4JAMPAIGN /-V;' /*> REF: SC108 V____ ____ BENDEX ANTI-WHEEL LOCK CONTROLLER (F,R, U,DM,DMM,RM, MB,MR,MC,RD, Having Axle-By-Axle Controller) PURPOSE To notify the field that the electrical portion of this system must be disconnected to prevent a possible "no brake" condition. INFORMATION AND RECOMMENDATION The Heavy Vehicle Systems Group of the Bendix Corporation has notified Mack Trucks. Inc. that defects exist in certain anti-wheel lock controllers that could cause brakes on the rear axle(s) to be inoperative. This defect involves a zener diode which may fail and al low current to continue flowing to the controller solenoid when no brake modu lation is required. When the solenoid is energized, brake system air cannot pass through the controller to actuate the brakes. This "no brake" condition can occur when the solenoid is activated, either by the system self-check when the key switch is turned on or during an actual anti-wheel lock cycle. This condition will occur without a visual warning to the vehicle operator. Approximately 1065 vehicles built from August 1977 throuch September 1978 are affected. A list of these vehicles will be sent to those branches and dis tributors that received vehicles requiring correction. NOTE This campaign (SC108) does not duplicate campaign SC106 which was announced in Service Bulletin Q1020 under BRAKES. Campaign SC106 covers six-u'heel chassis using one controller for both axles of the bogie. Campaign SC108 covers either four or six-wheel chassis using a separate controller for each rear axle. CIRCULATION Service Manager Shop Foreman Night Foreman Night Foreman Inspector Leadman Inspector Leadman Inspector Leadman Unit Over haul Room ftlN U U in USA Page 1 (Continued Page 2) Service Operations, Allentown. Pa., U.S.A. Shop Olllce DECEMBER 21. 1978 NOTE The anti-wheel lock warning light will remain on after the disconnection. IMPORTANT WARNING BE SURE THE NOTICE LABEL SUPPLIED TO YOU IS AFFIXED TO THE INSTRUMENT PANEL IN FULL VIEW OF THE VEHICLE DRIVER. NOTICE The Wheel Anti-Lock System on this Vehicle has been made Inoperative by Disconnecting the Power Supply. The Brakes are Fully Driver Controlled. 4 MR 1452 Reimbursement Submit an RWR to recover expenses incurred in disconnecting the anti-wheel lock system. Follow procedures given in Service Bulletin AJ1000 under POLICY. The standard $25. 00 minimum for claims is waived and an RWR is to be submitted for each vehicle campaigned. Show the following information on RWR form. Under Enter Description of Failure....................................... Service Bulletin Q1021 Failed Part Number........................................... SC1Q8 Part Name ............................................................ Controller Maximum Labor Time -- 0. 3 hour per controller END Page 3 Q102I BULLETIN MARCH 23, 1979 No. 01016 under brakes for branches and distributors only. (Supersedes Bulletin dated JULY 7, 1978) CHASSIS AFFECTED ALLENTOWN0" HAYWARDG OAKVILLE^ MANDATORY SAFETY CAMPAIGN REF: SC095 BRAKE FITTING TEE BRACKET (F,R and U Models With SW&6 and SW5? Series Bogies In On-Highway Service) PURPOSE To request the recall of subject vehicles for the purpose of replacing the brake fitting tee bracket. Bracket failure and subsequent air line damage can cause an automatic application of the spring brakes, thereby creating a potential traffic hazard. INFORMATION AND RECOMMENDATION The brake fitting tee bracket mounted on the front carrier is subject to failure caused by vibration. A bracket failure leaves the tee fitting unsupported and can result in a broken hose or connector fitting. Should this occur, loss of air pressure will cause the spring brakes to apply automatically. This condition occurs without prior warning to the operator. Approximately 33,000 vehicles, manufactured between March 1, 1975 and February 1, 1978 are involved in this recall. A list of these vehicles will be sent to all affected branches and distributors. Procedure CIRCULATION Remove existing tee bracket and install new bracket. The bracket is located on S.rvics Manager the forward axle carrier and uses the carrier mounting bolts for attachement. Shop See Figure 1. Tighten the attaching bolts 134 to 148 lb. ft. torque at installation Foreman of new bracket. Night Foreman Night Foreman Inapector Leadman Inapector Leadman Inspector Leadman Unit Over haul Room Page 1 Q1Q16 (Continued Page 2) Service Operations, Allentown, Pa., U.S.A. Shop Office BULLETIN APRIL 11, 1979 No. Qioi8 under brakes for branches and distributors only. (Supersedes Bulletin dated SEPTEMBER 13, 1978) CHASSIS AFFECTED ALLENTOWNG HAYWARDSZf OAKVILLEG MANDATORY SAFETY CAMPAIGN REF: SC098 AIR START RESERVOIR (Mack Western Models FL, FS,RL,RS, WL and WS With Aluminum Reservoir) PURPOSE To notify the field that the aluminum air start reservoir used on certain of these vehicles must be replaced, The reservoirs presently installed are subject to failure which can cause personal injury. INFORMATION ANT) RECOMMENDATION We have determined the aluminum air start reservoir does not have adequate strength because of an inherent de sign deficiency. Should a reservoir fail, the resultant explosive force could propel metal fragments in all directions with sufficient velocity to injure people in the area. We will recall approximately 268 vehicles, built between January 3, 1974 and December 31, 1977 for replacement of affected reservoir. A list of these vehi cles will be furnished at a later date to affected branches and distributors. Procedure Check part number of existing reservoir located on the identification and test plate before starting installation of a new one. Some chassis appearing on cam paign chassis listing may have been built with air start reservoir 22QE39319P1. These are satisfactory and DO NOT require change. If the vehicle is equipped with suspect reservoir 22QE39309, install new, re designed reservoir 22QE39320. No piping changes are required, however, the new reservoir has a larger outside diameter which affects the mounting. To permit use of the standard mounting straps, an extension adapter is required. The adapter attaches to end of strap and is secured with a jam nut. NOTE Some 22QE39309 reservoirs may have been misstamped22QE39303; these are also to be changed on a campaign basis CIRCULATION S.rvic. Manag.r Shop Foreman Night Foreman Night Foreman Inspector Laadman Inspector Laadman Inspector Laadman Unit Over haul Room Drain pressure from air system and air start reservoir. Disconnect air lines and remove reservoir from chassis. Install new reservoir and reconnect air lines. Charge system and check for leaks. ____________ Page 1 (Continued Page 2)________________MM Service Operations, Allentown, Pa., U.S.A. Shop Otflce BULLETIN JULY 9, 1979 No. Q1021a under BRAKES FOR BRANCHES AND DISTRIBUTORS ONLY. y y CHASSIS AFFECTED ALLENTOWN HAYWARDD OAKVILLE MANDATORY SAFETY CAMPAIGN REF: SC108 BENDDC ANTI-WHEEL LOCK CONTROLLER (CF,F,R,U,DM,DMM,RM,MB,MR,MC and RD Having Axle-By-Axle Anti-Wheel Lock System) PURPOSE To advise that improved controllers are available. INFORMATION AND RECOMMENDATION An improved controller is now available to replace the ones subject to failure. These controllers are to be installed on vehicles originally equipped with controllers having a serial number from 001000 through and including 012958 and on which the anti-wheel lock electrical system was disconnected per Service Bulletin Q1021 under BRAKES. NOTE Due to the Federal Court decision affecting brake performance standards, an anti-wheel lock system is not required to meet current requirements. If the customer so desires, the system can be left disconnected. Procedure CIRCULATION Service Manager 1. Disconnect wheel speed sensor leads and ground wire and unfasten existing Shop controller(s) from valve(s). Do not remove valve(s) from chassis. Foreman Night 2. Transfer controller leads from old controller to new one. Be sure the con Foreman nections are correct for the vehicle ground. The same controller is used for positive and negative ground systems, the only difference being in the ground and continuity wire connections. See Figure 1 for negative ground systems and Figure 2 for positive ground systems. Night Foreman Inapactor Laadman Inapactor Laadman Inapactor Laadman Unit Over haul Room Page 1 (Continued Page 2) Service Operations, Allentown, Pa., U.S.A. Shop Office JULY 9, 1979 If these events occur, the system is functioning normally and the vehicle can be returned to service. If not, check the anti-wheel lock system using normal trouble shooting procedures. New Parts Order parts on an emergency requisition from the parts distribution center nor mally serving your area. State on the requisition that the parts are for a manda tory safety campaign per Service Bulletin Q1021a under BRAKES. Do not include any parts on this requisition that are not required for the campaign. Qtv. 1 Part Number AR I 145-289359 Anti-Wheel Lock Controller (Bendix-Pos. & Nee. Grd) Removed Parts . Prepare a FO-42 Form as described in Paragraph G Section IV of the Warranty Ad ministration ManuaL Under cause of failure list SC-108. Attach hard copy of this tag and the removed controller and ship it prepaid to the Bendix branch serving your location. Be sure a copy of your FO-42 and shipping documentis attached to the RWR. Reimbursement All expenses incurred in this campaign are to be recovered through RWR procedures as instructed in Service Bulletin AJ1000 under POLICY. Submit an RWR for each vehicle campaigned. Show following information on RWR form. Under Enter Description of Failure---------------------------- Service Bulletin Q1021a under BRAKES Failed Part Number -------------------------------SC 108 Part Name--------------------------------------------- Controller Maximum labor time: . 3 hour Inspection per Controller . 7 hour Replacement per Controller END Page 3 Q1021a RVICE BULLETIN JULY 17, 1979 No. Q1020a under BRAKES FOR BRANCHES AND DISTRIBUTORS ONLY. / S S CHASSIS AFFECTED ALLENTOWN0 HAYWARDS^OAKVILLE^ MANDATORY SAFETY CAMPAIGN REF: SC1O0 BOGIE ANTI-WHEEL LOCK SYSTEM Converting Single Bogie Controller System to Axle-by-Axle System (F,R,U,DM,DMM,RM,MB,MR,MC,RD,WL,WS,RL,RS,RWL and RWS) PURPOSE To provide instructions for converting vehicles originally equipped with a single bogie controller system to an axle-by-axle system and installing wheel speed sensors with larger gauge wires. This modification is the correction for controller malfunctions covered by Mandatory Safety Campaign SC106 and described in Service Bulletin Q1020 under BRAKES. INFORMATION AND RECOMMENDATION Owners of vehicles affected by this cam paign, who so desire, may have this modification performed at no charge. Because of a recent court ruling which negates the requirement for anti-wheel lock systems, it is the owner's option whether or not to have the anti-wheel lock system installed. Procedure Two systems, Eaton and Bendix are involved. With Eaton systems, two complete new valve/controller assemblies are used. With Bendix systems, only one new valve/controller assembly is required and a new controller is to be installed on present valve. Figure 1 illustrates the two types of valve/controller assemblies M lN ltO IN U lA 1. EATON VALVE/CONTROLLER ASSEMBLY 2. 8ENOIX VALVE/CONTROLLER ASSEMBLY FIGURE 1 INOENTIFYING VALVE VALVE/CONTROLLER ASSEMBLIES Page 1 (Continued Page 2) Service Operations, Allentown, Pa., U.S.A. CIRCULATION Sarvica Manager Shop Foreman Night Foreman Night Foreman Inapactor laadman Inapactor Laadman Inapactor Laadman Unit Over haul Room Shop Offlea s 1. CONTINUITY WIRE (RED! 2. WHEEL SPEED SENSOR LEAD. L.H. 3. WHEEL SPEED SENSOR LEAD. R.H. 4. GROUND WIRE (WHITE) 5. POWER/WARNING LEAD (LARGE CONNECTOR) 6. GROUND LINK FIGURE 3 BENOIX CONTROLLER CONNECTIONS TWO-SENSOR UNIT WITH NEGATIVE GROUND EATON SYSTEM 1. POWER/WARNING LEAD (LARGE CONNECTOR) 2. WHEEL SPEED SENSOR LEAD. L.H. 3. WHEEL SPEED SENSOR LEAO, R.H. 4. CONTINUITY WIRE (REO) 5. GROUND WIRE (WHITE) 6. GROUND LINK FIGURE 4 BENOIX CONTROLLER CONNECTION - TWO-SENSOR UNIT WITH POSITIVE GROUND If equipped with Eaton system, remove existing valve/controller assembly completely and install a new one. Reuse existing air supply line and power/warning lead. BENDIX AND EATON SYSTEMS 1. Controller Installation a. On both systems, remove and discard delivery line manifold fitting. Itis mounted on left hand frame rail, adjacent to bogie rear axle. See Figure 5, Item 4. 1. DELIVERY LINE FOR BOGIE FORWARD AXLE BRAKES 2. BRAKE CHAMBER (4) 3. TEE FITTING 4. MANIFOLD 5. DELIVERY LINE FOR BOGIE REAR AXLE BRAKES 6. CONTROLLER 7. SUPPLY LINE FROM RESERVOIR 8. APPLICATION LINE FROM BRAKE VALVE FIGURE 5 PIPING SCHEMATIC - BOGIE CONTROLLER SYSTEM (TO BE REMOVED) j A\ JULY 17, 1979 WIRE COLOR COOE: 8 = BLACK R " RED BL = BLUE G - GREEN RG " RED WITH GREEN TRACER RBL 7 REO WITH BLUE TRACER BW = BLACK WITH WHITE TRACER 1. CAB WIRING HARNESS 2. THIS WIRE REMOVED PER SERVICE BULLETIN Q1020 UNOER BRAKES. IT MUST BE RECONNECTED TO NO. 3 CIRCUIT BREAKER TERMINAL. 3. CIRCUIT BREAKER STRIP 4. *18 BLACK WIRE PART OF CAB WIRING HARNESS. THIS WIRE IS NOT USED WITH SINGLE BOGIE CONTROLLER. 5. ADDED WARNING LIGHT RELAY S. NO. 14 JUMPER WIRE (ADOED) 7. ORIGINAL WARNING LIGHT RELAY S. REMOVE FROM ORIGINAL RELAY AND CONNECT TO ADOED RELAY 9. GROUND TO MOUNTING SCREWS. FIGURE 7 RELAY WIRING DIAGRAM Relay location is as follows: R,RD,RM,DM,DMM and U models - On right hand side of dash panel inside cab, behind give compartment. F models - In front of riders seat, underneath the defroster duct. MB models - Behind electrical component access panel, in front of driver. MC and MR models - In electrical equipment compartment on passenger side of engine cover, behind access panel. WL and WS models - Behind access panel on passenger side of instrument panel, adjacent to the circuit breakers. RL,RS,RWL and RWS models with Evans heater/air conditioner - Cab side of dash panel, below glove compartment. RL, RS, RWL and RWS models with Red Dot heater/air conditioners - In center of cab above transmission tunnel. Page 5 Q1020a (Continued Page 6) JULY 17, 1979 c. Connect continuity cables as follows: See Figure 10. Use existing cable for forward controller. Disconnect it from the cab har ness (at dash panel), rotate 180 degrees and reconnect it, using male side of cab harness connector. Female side of cab connector is left open. d. Rim a new continuity cable, 41MR3527-P11 from rear controller forward to the cab harness at dash panel. Note from the illustration that the female side of the new continuity cable is to be connected to the female side of cab harness. To make this connection, it is necessary to fabricate an adapter cable having bullet type connectors at both ends. Make the cable from 14 gage wire (approximately 18 in. long) and two 0.180 diameter, SAE J928 connectors. 0X4, 1. CONTINUITY CABLE IN CAB WIRING HARNESS 2. ADAPTER CABLE X CONTINUITY CABLE FROM AOOED (REAR! CONTROLLER 4. CONTINUITY CABLE FROM ORIGINAL (FRONT) CONTROLLER lU e. Connect the new relay into the circuit as shown in Figure 7. This includes reconnecting the wire removed per Service Bulletin Q1020 under BRAKES. In addition a jumper wire (14 gage) must be added to connect the No. 2 ter minal of original relay to No. 2 terminal of the added relay. f. Remove existing wheel speed sensors and replace with the new ones shown in parts list. These sensors V.ave longer leads th?n original ones, elimi nating need for the intermediate sensor harness. The harness should be discarded. Exercise caution when routing and clamping sensor wires to avoid damage caused by relative motion of axle and frame. See Figure 11. 1. WHEEL SPEED SENSOR LEAD 2. SECURE SENSOR LEADS TO AXLE HOUSING WITH TIE BANOS 3. VALVE/CONTROLLER ASSEMBLY 4. SECURE SENSOR LEADS TO BRAKE HOSES WITH TIE BANDS (MAX. 9 IN. SPACING) 5. ROUTE SENSOR LEADS UNOER AXLE HOUSING (S-S0.58.SS SSI ONLY) FIGURE 11 WHEEL SPEED SENSOR LEAD ROUTING JULY 17, 1979 New Parts Order campaign parts on Emergency/Breakdown Parts Requisition form XG10 and process throught the Service Parts Distribution Center normally serving your area. Prefix the requisition number you assign with "Z". This will insure parts so ordered will not be cancelled. Also, show "DO NOT CANCEL" on face of the requisition used to order parts for safety campaign corrections. Do not include parts on this requisi tion that are not required for the campaign. NOTE Order either Eaton or Bendix valve/controller assemblies, depending on type originally installed. Qty. 2 1 1 1 1 or 1 or 1 1 Part Number 5MN401R + 5MN400R + 5MN402R 745-289359 41MR3516-P9 41MR3516-P13 41MR3516-P15 41MR3527-P11 DescriDtiQiL ... V alve and Controller Assembly (Eaton-Neg. Grd.) Valve and Controller Assembly (Bendix-Neg. Grd.) Valve and Controller Assembly (Bendix-Pos. Grd.) Controller (Bendix-Pos. or Neg. Grd.) Power/Warning Lead (Tractor) Power/Warning Lead (Truck under 220 in. W. B.) Power/Warning Lead (Truck - over 220 in. W. B.) Continuity Cable 4 9MN32-P2 1 2MR240-P2 1 63AX53267R 1 * 63AX51599R or 1 * * 63AX353 or 1 * * 63AX1799 1 63AX1251 2 43MR21-P4 - 5 50AX Wheel Speed Sensor Relay _ , Tee, 1/2 O. D. Tube x 3/8 O. D. x 3/8 NPT(App. Port) Tee, 5/8 O. D. Tube x 1/2 NPTF (Supp. Port) Tee, Flared Type, 3/8 NPTF X 1/2 O.D. Tube(App. Port) Tee, Flared Type, 1/2 NPTF x 5/8 Tube (Supp. Port) Bushing, 1/2 NPT x 3/4 NPT (Bendix only) Connector, Bullet Wire, 14 Gage Black * Use with Synflex tubing * * Use with Wire Braid hose +. See Note Page 2 Removed Parts Hold all removed parts for possible return. Removed material disposition instructions will be provided with the credit memo copy of the RWR when returned. Reimbursement Submit an RWR to recover expenses incurred in making this installation, following procedure given in Service Bulletin AJ1000 under POLICY. Show following informa tion on RWR form. ' RWR MUST SHOW SERIAL NUMBER FOR BENDIX CONTROLLER REMOVED. Under Enter Description of Failure--------------- Service Bulletin Q1020a under BRAKES Failed Part Number------------------- SC 106 Part Name------------------------------- Anti-Wheel Lock Maximum Labor Time ------------ 10. 6 hours END BULLETIN AUGUST 16, 1979 \0. Q1022 under brakes FOR BRANCHES AND DISTRIBUTORS ONLY. * jJ CHASSIS AFFECTED ALLENTOWN0 HAYWARD0/OAKVILLE2T MANDATORY SAFETY CAMPAIGN REF: SC113 ANTI-WHEEL LOCK VALVE (R,RD,RM,DM,DMM,F,MB,HMM,U,RL,RS,WL and WS Models With Eaton System) PURPOSE To provide a procedure for either repairing or permanently disabling the anti-wheel lock section of the anti-wheel lock valve. Some valves may malfunction and prevent application of the brakes or affected axle. INFORMATION AND RECOMMENDATION Accumulation of fluid contaminants in the valve, gen erally caused by poor maintenance practices, can cause the anti-wheel lock lock valve piston t swell and possibly bind. During an anti-wheel lock cycle, it is possible for the anti-wheel loci piston to bind in a position where no air will be delivered to the brake chambers served by that valve on subsequent service brake applications. If this condition should occur, the reduced br: king power would result in increased stopping distances without prior warning to the driver. Approximately 37,607 vehicles manufactured between October 1, 1974 and September 1, 1977 were equipped with the suspect valves. Valves affected are those bearing date codes 274-74 through 244-77 (See Figure 1). A list of these vehicles will be sent to affected branches and di tributors. NOTE A small quantity of valves were shipped with a slightly modified body that should not be rebuilt. These valves carry date codes (Julian) 231-75 through 241-75, which are stamped on the outer edge of the top end cover. If one of the above mentioned valves is found to require repair, please call the nearest Eaton Truck Components branch, which will provide an exchange valve. Northcentral (Kalamazoo, MI) - 616/385-5400 Northeast (Allentown, PA) - 215/797-7583 Southeast (Charlotte, NC) - 704/372-5840 Southwest (Tulsa, OK) - 918/622-0880 Western (San Leandro, CA) - 415/562-7555 Canadian (Toronto, Ontario) -416/678-2497 CIRCULATION Service Manager Shop Foreman Night Foreman Procedure Night Foreman Two courses of action are available to correct this possible condition. The me Inspector thod used is at the vehicle owner's choice. They are as follows: Leadman 1. Repair valve using an approved rebuilt kit with piston of improved material. Inspector Leadman Refer to Section A. .2 Disable the anti-wheel lock capability of the valve. Refer to Section B. Inspector Laadman Unit Over NOTE haul Room Method 2 cannot be used on vehicles equipped with high-torque front (steering) axle brakes unless the brakes are modified to be compatible with a non-anti-lock system. Brake modifications are to be made at customers expense and prior to any Mack Branch or Distributor disabling the anti-lock system. Shop Ottice _____________ Page 1 (Continued Page 2)____________________ Service Operations, Allentown, Pa.. U.S.A. rtlN ltD IN U iA 1. SOLENOID 2. 'O-RING (0.549 1.0.) 3. '0-RING (0.239 1.0.) 4. BIAS ORIFICE 5. 'DIAPHRAGM S. PRIMARY PISTON 7. 'O-RING (2.675 I.O.) 8. '0-RING (1.862 1.0.) 9. RETAINING BOLTS. S/16 (SQUARE HEAD) 10. BIAS ENO CAP IQ 11. 'GASKET 12. KEY 13. 'SECONDARY HOUSING ASSEMBLY 14. VALVE BODY 15. 'FILTERS 16. 'CHECK VALVE ASSEMBLY 17. TOP ENO CAP 18. RETAINING BOLT NUTS -PART OF REBUILO KIT FIGURE 2 INSTALLING REBUILD KIT Cleaning and Inspection 1. Wash all metal parts in good grade commercial cleaning solvent and dry thoroughly. Care will be necessary to see that sealing ridges on both end caps are not damaged through handling or reassembling. 2. Inspect all metal castings for cracks or breakage which may have occurred during operation. Threaded ports and valve seats should also be examined for damage. Do not use valves with damaged castings for rebuilding. If damage is evident, replace the valve. 3. Small amounts of adhesive were used to attach diaphragm and gasket to end caps during assembly/ Any dried adhesive scale should be scraped from end caps. Care must be taken not to gouge surface area, to elimi nate the possibility of leakage after reassembly. 4. Those used parts for which replacements are provided in the repair kit should be discarded. Page 3 Q1022 (Continued Page 4) AUGUST 16. 1979 *2 *4 FIGURE 3 NUT TIGHTENING SEQUENCE Test Procedure Upon completion of the anti-wheel lock control valve rebuild procedure, the skid con trol valve should be given a full operational and leakage test. This can be done by reinstalling the valve on the vehicle or using a fabricated test fixture. An accurate pressure gauge with a minimum 2" face is recommended for checking delivery pres sures. Additional gauges for reservoir pressure and application pressure are re quired for fixture testing. 1. After mounting the air valve, minus the controller, connect only the supply port to the line from the air supply reservoir for the first test. 2. Apply a soap solution at the exhaust port, completely covering the exhaust port round rubber baffle with the soap solution. Also place the soap solu tion around the edges of both the diaphragm and bias gasket. 3. Charge system reservoir pressure which feeds the valve supply port to ap proximately 100 p. s. i. Then check the soap solutioned areas to be sure there is no excessive leakage (1" bubble permitted in 3 seconds). If leakage exceeds this rate, check for damaged or displaced "O" rings and/or foreign material under supply valve seat. Reassemble and retest. 4. Connect application port to the application line coming from treadle valve. Connect delivery port so that the 2" air gauge is inserted into (a) an extra port in the service chamber, (b) a tee placed in the delivery line, or (c) an unused valve delivery port. This gauge is used for test procedure only, and is to be removed prior to operation of vehicle. 5. Again apply soap solution as in Step 2, plus at fitting ports and at the ex haust port. Proceed to next step. 6. Make a full application to the service brake system. Check soap solutioned areas to again be sure there is no excessive leakage (1" soap bubble in 3 seconds is the acceptable industry leakage rate allowance). 7. Release application pressure after completing leakage test. Reapply full service brake rapidly and observe air gauge in the delivery line. The de livery pressure is to rise to within 10 p. s. i. of reservoir in less than 1 second. 8. When making a quick release of the application pressure (treadle valve), the delivery pressure should drop to zero p. s. i. in less than 1 second. 9. To check the skid control function of the relay valve, fully apply and hold brakes, and then apply 12 volts D. C. to the air valve solenoid terminal blades. This should fully exhaust the brakes within 1-2 seconds. Paerp 5 01022 (Continued Paere 6) AUGUST 16, 1979 1. SOLENOID 2. BRACKET RETAINING NUTS 3. CONVERSION PLUGBRACKET . CONVERSION PLUG * O-WNQ 6. SOLENOID RECESS CAVITY 7. STUD O -RINGS FIGURE 4 INSTALLING ANTI-WHEEL LOCK 0ISA8LING KIT 1. After detaching the controller from the air valve assembly, remove the two 5/16 in. nuts (2) using a 1/2" socket or wrench, holding the solenoid on the mounting studs (7). (Save the two 5/16 in. nuts for reuse). 2. Carefully remove the solenoid (1) from its stud mounted position by lifting it straight up. If both "O" rings (8) do not come out with the solenoid, in spect the solenoid recess cavity to find them. Remove and discard them along with the solenoid. 3. Prior to installing the new "O" ring (5), clean the solenoid recess cavity of any dirt, grease or foreign material. 4. Lubricate the conversion plug"0" ring (5), with silicone grease and place it on the conversion plug (4). 5. Install the conversion plug (4) in the solenoid recess cavity with the "O" ring down. 6. Place the conversion bracket (3) onto the solenoid mounting studs (7). 7. Install the two 5/16 in. nuts (2) on the studs (7) and tighten to 125-150 lbs. in. torque. 8. Check the conversion kit for leakage by applying and holding a full brake pedal application while covering the area around the conversion plug with soap and water. No leakage is permitted. Page 7 Q1022 (Continued Page 8) AUGUST 16, 1979 Reimbursement All expenses incurred in this campaign are to be recovered through RWR procedures as instructed in Service Bulletin AJ1000 under POLICY. Submit an RWR for each vehicle campaigned. Include following information on RWR form. Under Enter Description of Failure------------------------------ Service Bulletin Q1022 under BRAKES Failed Part Number---------------------------------SC 113 Part Name---------------------------------------------- Anti-Wheel Lock Valve Maximum labor allowance: Installing rebuild kit--------------- 1.6 hours Installing disable kit------------ -- 0.4 hours END Page 9 Q1022 (Continued Page 10) DIRECT DIAL (407) 244-1165 DIRECT FACSIMILE (407)648-4664 INTERNET E-MAIL CKOLOS MVW.COM Maguire, Voorhis & Wells, P.A. CJ&ttc'fweyi at TWO SOUTH ORANGE PLAZA 2 SOUTH ORANGE AVENUE ORLANDO, FLORIDA 32801 TELEPHONE (407) 244-1100 FACSIMILE (407) 423-8796 -- P.O. BOX 633 ORLANDO, FLORIDA 32802 July 17, 1997 Chris N. Kolos David M. Lipman, Esq. 599 SW 74th Street Suite 304 Miami, FL 33143 Re: Anne M. Tinker, Executrix of the Estate of Timothy W. Tinker, Deceased vs. A.E. Clevite, et a/. Ontario County Index No. 83778. Dear Mir. Lipman: My letter of July 2, 1 997 was not quite right. Enclosed please find what truly is the final production to be made by Mack Trucks, Inc. in response to paragraphs 7 and 11 of Plaintiff's Request for Production. If you have any questions regarding the above, please do not hesitate to contact me. CNK:jo Enclosures ORLANDO MELBOURNE TALLAHASSEE