Possible Oil Leak Areas 2.5L L4
FIG. 1 - Top view of Cover and Baffle:
Rocker Cover (see Figure 1)
1. Rear and exhaust side of rocker cover.
2. Clean sealing surfaces on valve cover and cylinder head. Use degreaser to dry surfaces.
3. Apply a continuous 3/16" (5 mm) diameter bead of RTV sealant (P/N 1052366 or equivalent) around cylinder head sealant surface inboard at bolt holes.
NOTICE: Keep sealant out of the bolt holes to prevent damage to the cylinder head. The use of gaskets may not be successful in correcting oil leaks around rocker arm covers, therefore, the use of the RTV listed in this bulletin is recommended over gasket replacement.
If attempted rocker cover sealing procedures outlined above are unsuccessful, replace rocker arm cover with P/N 10030209 (pre-1984 only). The sealing rail of P/N 10030209 cover is dimpled to allow application of a consistent layer of sealer between cover and cylinder head.
FIG. 1 - Top view of Cover and Baffle:
Oil Fill Cap (see Figure 1)
1. To correct this condition, lightly tap on oil fill cap to seal cap to rocker cover.
FIG. 2 - Side View of Pushrod Cover:
Side View of Engine Block (see Figure 2)
1. The area near the oil sending unit may indicate an oil leak. This can result from oil run-off during production of the engine and installation of the oil sending unit. In order to verify an oil leak, it may be necessary to spray the area with degreaser and retest. This applies only to new car deliveries.
FIG. 3 - Oil Drain Plug:
Oil Drain Plug (see Figure 3)
1. It may be necessary to remove oil drain plug and insert a nylon washer on drain plug to correct repeat cases of oil leaks at drain plug.
FIG. 4 - Oil Pan Front Cover:
Front Timing Cover Crankshaft Seal (see Figure 4)
1. Install using tool J-23042. Lip must be toward rear of engine.
2. Lubricate balancer and seal lip with engine oil. Install hub on crankshaft, bottom out against crankshaft gear. Install drive belt and tension to specification.
Oil Pan Front Seal to Front Cover (see Figure 4)
1. Apply a 3/8" wide by 3/16" bead of RTV to joint at oil pan and timing cover.
2. Apply a 1/4" wide by 1/8" thick bead of RTV sealer to timing cover at timing cover to block mating surfaces.
3. Install center tool J-23042 in timing cover oil seal.
4. Install timing cover to block, partially tighten two
(2) oil pan to cover screws.
5. Install remaining cover to block screws.
6. Torque to 10 N-m (90 in.lb.).
FIGURE 5 - REAR CAM PLUG:
Rear Oil Gallery Plug (see Figure 5)
1. Remove plug and reseal with RTV.
Oil Pan and Rear Oil Pan Seal (see Figure 5)
1. Apply a 3/8" wide by 3/16" thick bead of RTV sealer to rear of oil pan.
2. Apply a 3/16" wide by 1/8" thick bead of RTV sealer at rear corners of oil pan.
3. Apply a 3/16" wide by 1/8" thick bead of RTV to rear of engine block assembly.
4. Groove in main bearing cap must be filled flush to 1/8" above surface with RTV.
NOTICE: 1984 production main bearing cap has no groove; apply sealer direct to casting surface.
Rear Main Bearing Seal (Figure 5)
The rear main bearing oil seal is a one (1) piece unit and can be replaced without removal of oil pan or crankshaft. To properly diagnose rear main seal oil leaks, allow engine to run at least five (5) minutes to properly circulate the flourescent dye additive, remove transmission and flywheel, and, using black light J-28428-B, shine back end area of block.
To install new rear main bearing seal:
1. Clean block and crankshaft to seal mating surfaces.
2. Soak the seal in clean engine oil for at least five (5) minutes.
3. Press evenly into place with finger pressure only.
4. Install flywheel to 60 N-m (44 ft.lb.).
5. Reinstall transaxle.
NOTICE: Do not apply sealer to the rear main bearing seal. This may prevent proper seating of the seal to the recess in the block.
For detailed procedures on sealing 2.5L engines, refer to Section 6-A in the Celebrity, Citation and Camaro Service Manuals.
FIGURE 5 - REAR CAM PLUG:
Rear Cam Plug (see Figure 5)
1. Repair using GMS Type A (GE 1673) GM P/N 1052915 or equivalent.
(#5 MAIN BEARING CAP ATTACHING SURFACE ON CYLINDER BLOCK ASM.):
Main Bearing Cap Attaching Surface on Cylinder Block Assembly (see Figure 6)
1. Apply 1/4" wide by 1/8" thick across parting line of rear main bearing as shown. Use P/N 1052357 (Loctite 514) or equivalent anaerobic sealer.
Sealing surfaces which receive sealant must be free of oil and foreign material.