OIL LEAK DETECTION BLACK LIGHT INFORMATION

Model and Year 1978-80 MONZA, 1980-84 CITATION, 1982-84 CELEBRITY AND CAMARO

To assist in black light diagnosis of oil leaks, all 2.5L four cylinder engines produced by Pontiac for the 1984 model year have dye added to the engine oil during production.

BLACK LIGHT PROCESS CHECK

This method uses a flourescent dye added to the engine oil (dye is available from one source, that is Kent-Moore distributors). One (1) ounce of dye should be circulated in the engine oil for a minimum of five (5) minutes. In some cases, it may be necessary to drive the car before the dye will show. Ideal situation is to install dye in the customers vehicle a few days before the scheduled repair. Prior to the black light inspection of the engine, the dipstick should be held under the black light to assure that the dye has mixed thoroughly with the engine oil. Oil with dye additive will be a bright yellow when exposed to a black light. Oil without dye additive will show a light purple in color. It is not necessary to clean the engine prior to inspection. The difference between oil leaking with the dye additive versus old oil is quite evident.

EXTERNAL AIR PRESSURE

An adapter with an air fitting can be made to fit into PCV hole of the rocker arm cover or dipstick hole. This can be attached to an air supply that is regulated at 2 to 3 psi. Extreme caution should be used to assure that air pressure does not exceed 3 psi. Leaks could be created if air pressure exceeds 3 psi. The air cleaner pipe to rocker arm cover hole must be plugged. With air being forced into the crankcase, the oil will be pushed to the source of the oil leak, where it can be detected with the black light. If a black light is not being used, sometimes spraying the suspected area with soapy water will confirm the leak. Test can be performed with or without the engine running.

INTERNAL PRESSURE

This can be accomplished by making the PCV valve inactive and blocking off the air cleaner inlet to the RAC hole. By running an engine in a closed system, crankcase pressure will build up and force oil to the source. This method can build up extreme pressure and should be monitored by periodically removing the dipstick to relieve the crank-case pressure.

COMPONENT REMOVAL

To properly detect an oil leak at the rear of an engine, it is necessary to remove the transmission. This process, in conjunction with black light, will eliminate all guess work in regards to rear oil leaks.

NOTICE: When analyzing an engine with the black light and flourescent dye method, the following variables can sometimes occur. The technician using the black light should be aware of the following:

Short run times will not always allow dye to surface at suspected oil leak area. Recommendation: pressurize engine.

Extended run times can sometimes spread dye over a large area, which may cause actual leak detection to become most difficult. Recommendation: clean and pressurize engine.

RECOMMENDED SEALER USAGE ON OIL LEAKS

GMS Type A (GE 1673), GM P/N 1052915 or equivalent. Use P/N 1052366 (SWS T56) for higher temperature applications.

It is imperative to adhere to the following steps in order to correct oil leaks by use of RTV'S.

1. Clean metal surfaces free of oil, grease, corrosion, etc.

CAUTION:

Do not use gasoline or other petroleum base solvents as they can leave a residue preventing adhesion of the sealant to the metal surfaces.

To clean surface to be sealed, use brake cleaner or equivalent chlorinated solvent.

2. On sealant tube, cut tube extension to approximately 1/8" opening. Apply to one (1) of the bonding surfaces. Totally circle all bolt holes.

3. Inspect bead for uniformity, air pocket voids, thin areas, or skips.

4. Assemble sealing surfaces immediately in order to prevent drying of the sealant (three (3) minutes maximum). Do not allow RTV to skin over.

5. Torque to specification. Be careful not to over torque.

6. Allow sealant to dry for fifteen (15) minutes prior to checking engine for oil leaks.

7. Allow RTV to cure for approximately one (1) hour before placing vehicle in service.

POSSIBLE OIL LEAK AREAS 2.5L L4 ------------------------------- 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" (5mm) 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.

Oil Fill Cap (see Figure 1)

1. To correct this condition, lightly tap on oil fill cap to seal cap to rocker 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 neces- sary to spray the area with degreaser and retest. This applies only to new car deliveries.

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.

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 lb. in.).

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 lb. ft.).

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

Rear Cam Plug (see Figure 5)

1. Repair using GMS Type A (GE 1673) GM P/N 1052915 or equivalent.

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.

WARRANTY INFORMATION

1. Black light leak check without components removal:

Includes hoist time for leak check or engine bottom-end (pan gasket, timing chain cover, etc.), valve cover and side covers.

Carline Labor Operation Time

Celebrity, Citation and Camaro T-3122 .5 hrs.

2. Black light leak check requiring component removal:

Includes labor operation T-3122 as well as time for transmission R&R, flexplate or flywheel R&R. Do not claim T-3122 in addition to any labor operations listed below.

Carline Labor Operation Time ------- --------------- ---- Celebrity, Citation and Camaro Manual Transmission T-3123 3.9 hrs.

General Motors bulletins are intended for use by professional technicians, not a "do-it-yourselfer". They are written to inform those technicians of conditions that may occur on some vehicles, or to provide information that could assist in the proper service of a vehicle. Properly trained technicians have the equipment, tools, safety instructions and know-how to do a job properly and safely. If a condition is described, do not assume that the bulletin applies to your vehicle, or that your vehicle will have that condition. See a General Motors dealer servicing your brand of General Motors vehicle for information on whether your vehicle may benefit from the information.