CLUTCH PEDAL FREE TRAVEL (REVISED ADJUSTMENT PROC.)

THE FOLLOWING INFORMATION CONCERNING REVISED CLUTCH PEDAL FREE-TRAVEL, SUPPLEMENTS INFORMATION FOUND IN CHEVROLET DEALER SERVICE BULLETIN 86-66 DATED APRIL 1986. THIS SUPPLEMENT SHOULD BE ATTACHED TO BULLETIN 86-66. THIS BULLETIN CONTAINS INSTRUCTIONS AND ILLUSTRATIONS FOR THE REVISED PROCEDURE FOR CLUTCH PEDAL FREE-TRAVEL ADJUSTMENT. ADJUSTMENT IS NECESSARY WHEN THE PEDAL FREE-TRAVEL IS REDUCED TO LESS THAN 19MM (3/4 IN.). PROPER FREE-TRAVEL IS 25MM TO 50MM (1.0 IN. TO 2.0 IN.). ADJUSTMENT IS MADE BY SHORTENING OR LENGTHENING THE CONTROL ROD AT THE CLUTCH RELEASE LEVER. REFER TO THE ATTACHED DATA TABLE FOR ADDITIONAL INFORMATION. THE 1986 SERVICE MANUAL WILL INCLUDE THIS NEW ADJUSTMENT PROCEDURE. ROD AND LEVER TYPE MODELS WITH 4.8L (292 CID), 5.7L (350 CID), AND 6.0L (366 CID) GASOLINE ENGINES (REFER TO FIGURE NO. 1) 1. DISCONNECT THE RETURN SPRING AND LOOSEN NUTS (3 AND 8). 2. APPLY ABOUT 2KG (5 POUNDS) FORCE TO THE PUSH ROD (6) IN THE DIRECTION OF THE ARROW (7) TO REMOVE THE LINKAGE CLEARANCES. 3. APPLY ABOUT 2KG (5 POUNDS) FORCE TO THE CLUTCH LEVER (1) IN THE DIRECTION OF THE ARROW (2) TO REMOVE CLEARANCE BETWEEN THE RELEASE BEARING AND THE CLUTCH INTERNAL RELEASE FINGERS. 4. TURN NUT (3) TO OBTAIN 10MM (0.40 IN.) BETWEEN THE NUT (3) AND THE SWIVEL (5). 5. TIGHTEN THE NUT (8) TO JAM THE SWIVEL AGAINST THE NUT (3). CONNECT THE RETURN SPRING. CHECK THE OPERATION OF THE CLUTCH LINKAGE. MODELS WITH DIESEL ENGINES OR 7.0L (427 CID) GASOLINE ENGINES (REFER TO FIGURE NO. 2) 1. BLOCK THE PEDAL AGAINST THE PEDAL BUMPER STOP WITH THE CLUTCH IN THE ENGAGED POSITION. 2. DISENGAGE THE CLUTCH LEVER RETURN SPRING (6). 3. LOOSEN THE JAM NUTS AT THE TURNBUCKLE (4). 4. HOLD THE CLUTCH LEVER WITH THE V-NUT OR TRUNNION REARWARD, PLACING THE THROW-OUT BEARING IN CONTACT WITH THE CLUTCH FINGERS. 5. ADJUST THE TURNBUCKLE TO THE DIMENSION SHOWN IN FIGURE NO. 2 FOR CLEARANCE BETWEEN THE V-NUT OR TRUNNION AND THE HEAD OF THE TURNBUCKLE BOLT. 6. TIGHTEN THE JAM NUTS AGAINST THE TURNBUCKLE AND CONNECT THE CLUTCH LEVER RETURN SPRING. 7. AFTER ADJUSTING THE LINKAGE, CYCLE THE CLUTCH PEDAL TO VERIFY THAT THE PEDAL "FREE-TRAVEL" IS RELEASE BEARING CLEARANCE AND NOT LOST MOTION IN THE LINKAGE DUE TO WORN BUSHINGS, SHAFTS, OR LINKAGE ARMS. CABLE AND LEVER TYPE MODELS WITH 6.0L (366 CID) OR 5.7L (350 CID) GASOLINE ENGINES OR 8.2L DIESEL ENGINES (REFER TO FIGURE NO. 3). 1. BLOCK THE CLUTCH PEDAL AGAINST THE PEDAL BUMPER STOP (CLUTCH ENGAGED POSITION). 2. DISENGAGE THE CLUTCH LEVER RETURN SPRING AT THE TRANSMISSION. 3. LOOSEN THE CLUTCH CABLE JAM NUT AT THE CLUTCH RELEASE LEVER. 4. HOLD THE CLUTCH LEVER WITH THE V-NUT OR TRUNNION REARWARD, PLACING THE THROW-OUT BEARING IN CONTACT WITH THE CLUTCH LEVER FINGERS. 5. SET THE ADJUSTER NUT TO THE DIMENSION SHOWN IN FIGURE NO. 3, ITEMS 7 AND 10. 6. V-NUT TYPE - TIGHTEN THE JAM NUT AGAINST THE ADJUSTER NUT. TRUNNION TYPE - TIGHTEN THE JAM NUT TO JAM THE TRUNNION AGAINST THE ADJUSTER NUT. 7. CONNECT THE CLUTCH LEVER RETURN SPRING AND CHECK THE OPERATION OF THE CLUTCH LINKAGE. C7 MODEL WITH 3208 DIESEL ENGINE (REFER TO FIGURE NO. 4) 1. BLOCK THE PEDAL AGAINST THE PEDAL BUMPER STOP WITH THE CLUTCH IN THE ENGAGED POSITION. 2. DISCONNECT THE CLUTCH LEVER RETURN SPRING AT THE LEVER. 3. LOOSEN THE JAM NUT AND ADJUSTER NUT AT THE RELEASE LEVER TRUNNION. 4. APPLY ABOUT 2 KG (5 POUNDS) FORCE TO THE CLUTCH LEVER IN THE DIRECTION OF ARROW "A" (FIGURE NO. 4) TO REMOVE CLEARANCE BETWEEN THE RELEASE BEARING AND THE CLUTCH INTERNAL RELEASE FINGERS. 5. WHILE HOLDING THE LEVER REARWARD AS DESCRIBED IN STEP 4, CHECK AND ADJUSTER FOR DIMENSION "B". 6. ONCE DIMENSION "B" IS SET, TIGHTEN THE JAM NUT AGAINST THE TRUNNION TO REMOVE ALL CLEARANCE. 7. CONNECT THE CLUTCH LEVER RETURN SPRING AT THE LEVER AND CHECK THE LINKAGE FOR OPERATION. MEDIUM DUTY CLUTCH ADJUSTMENT TABLE ADJUSTER NUT ENGINE HOUSING CLUTCH DIMENSION 4.8L BELL (APRON) 12/1 PUSH 10 MM (0.40 IN.) 5.7L BELL (APRON) 13/1 PUSH 10 MM (0.40 IN.) 6.0L BELL (APRON) 13/1 PUSH 10 MM (0.40 IN.) 7.0L SAE #2 (2 PIECE) 14/1 PUSH 12 MM (0.45 IN.) 8.2 SAE #2 (2 PIECE) 14/1 PUSH 12 MM (0.45 IN.) N/T 14/2 PUSH 3208 SAE #2 (2 PIECE) 14/1 PUSH 12 MM (0.45 IN.) N/T 14/1 PULL 7 MM (0.28 IN.) 14/2 PULL 7 MM (0.28 IN.)

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