Service & Parts Information
SERVICE PROCEDURE1. Open hood.
2. Inspect engine identification paper tag located on engine timing cover. If the engine identification tag is missing, the engine identification number is engraved on a horizontal boss located on the cylinder block, directly underneath the #4 spark plug.
3. If engine serial number is between 77117 and 83420, proceed to Step 5. Replacement of ten (10) engine main bearing cap bolts is needed.
4. If engine serial number is not between 77117 and 83420, vehicle passes inspection and no repair is needed. Proceed to Step 19.
Main Bearing Bolt Replacement
5. Hoist vehicle. If a twin post is being used, position jackstand at vehicle jacking points and lower post.
6. Drain oil from crankcase.
7. Remove exhaust pipe from exhaust manifold.
8. If equipped with air conditioning, remove lower air conditioning strut bracket.
9. Remove flywheel dust shield.
10. Remove oil pan. Slide the oil pan forward, then downward to clear the oil pump pickup tube.
11. Inspect for broken bolts and then replace the ten (10) main bearing cap bolts. Torque new main bearing cap bolts to 77 N-m (57 ft.lb.).
11a. If any broken bolts are found in the #1, #2, #3 or #4 main bearing positions, remove the main bearing cap and inspect the bearing.
11b. If any main bearings appear to be damaged or have spun, replace the bearing.
11c. If a broken bolt is found in the #5 main bearing position, visually inspect the cap to determine whether the bearing has moved. If the bearing cap has not moved, replace the bearing cap bolts only.
11d. If removal of #5 main bearing cap is necessary, the area requiring sealer must be cleaned and resealed using dealer kit GM #3997597. Refer to illustration of the 1983 Front Wheel Drive Service Manual, Section 6A2, Figure 6A2-38. Be sure the rear main oil seal is properly aligned.
11e. If the engine block has been damaged as a result of a spun bearing, replace the engine block.
12. Install oil pan and new oil pan gasket. Apply RTV sealer to oil pan gasket at the oil pump mating surface.
13. If equipped with air conditioning, install air conditioning strut bracket.
14. Install flywheel dust shield.
15. Install exhaust pipe to exhaust manifold.
16. Lower vehicle.
17. Refill crankcase with oil.
18. Start engine and check for oil leaks.
19. Each vehicle modified in accordance with the instructions outlined in this service procedure will require a campaign identification label. Each label provides a space to include the campaign number, the five-digit dealer code of the dealer performing the campaign service, and the date vehicle was campaigned.. This information may be inserted with a typewriter or ballpoint pen. Install the label on the fan shroud where it is readily visible.
PARTS INFORMATION
Campaign requirements of part number 11072446 (bearing bolts - ten (10) per vehicle) are to be obtained by the dealer from WDDGM.
The removed parts are to be retained for disposition by zone personnel.
Very few vehicles will need replacement of engine main bearing cap bolts.