[Manitcor]

Subject: Engine Oil Pan Leak (Seal with RTV Sealant)


Models: 1995-2001 Buick LeSabre, Park Avenue
1996-1999 Buick Riviera
1996-2001 Buick Regal
1997-2001 Buick Century
1998-2000 Chevrolet Lumina
1998-2001 Chevrolet Monte Carlo
2000-2001 Chevrolet Impala
1995-1996 Oldsmobile Ninety-Eight
1995-1999 Oldsmobile Eighty-Eight
1998-1999 Oldsmobile Intrigue
1995-2001 Pontiac Bonneville
1996-2000 Pontiac Grand Prix
3.8 L V6 Engine (VINs K, 1 -- RPOs L36, L67) and Stamped Steel Oil Pan


Condition:
Some owners may comment on a repeat engine oil pan leak.


Cause:
Engine oil pan leak may be due to an uneven (rippled) sealing surface on the oil pan.


Correction:
Seal leak with RTV sealant using the following procedure:
Remove the oil pan from the engine. Follow oil pan removal instructions found in the Engine Mechanical section of the Service Manual.
Remove old RTV sealant from the engine block at the joint face sealing surfaces and the oil pan. Use only a plastic or metal scraper as described in Corporate Service Bulletin #00-06-01-012.


Important:
Ripples which appear in the oil pan sealing rail surfaces of the oil pan will not affect sealability when using this procedure. Do not replace oil pan for this condition.
Inspect the oil pan sealing rail surface for bends or distortion which would affect sealability.
Clean the engine block and oil pan mating surfaces using a solvent that leaves no residue, such as P/N 12346139 (in Canada, P/N 10953463), or equivalent.


Important:
In the steps that follow, it is strongly recommended to use a 5 oz. (142 ml) RTV sealant cartridge and a hand-actuated caulking gun. This will help assure that a continuous bead of RTV sealant will be applied to the gasket surfaces.
Use a new oil pan gasket and windage tray assembly, P/N 24502397.


Figure 1


See illustration above. Apply a continuous 1/4 inch bead of 5900 RTV sealant, P/N 12346286, to the bottom of the new gasket. Apply the RTV sealant directly over the gasket's raised sealing bead.
Install the gasket onto the oil pan and align the oil pan bolt fastening holes with the gasket.


Figure 2


See illustration above. Apply a continuous 1/4 inch bead of 5900 RTV sealant, P/N 12346286, on the top of the new gasket. Apply RTV sealant directly over the gasket's raised sealing bead.
Install the oil pan on the engine. Tighten
Tighten the oil pan retaining bolts to 14 N·m (124 lb in).
Follow the remaining oil pan installation instructions found in the Engine Mechanical section of the Service Manual.
Before adding engine oil, allow the RTV to set for 30 minutes.
Run the engine and verify the repair.


Parts Information:
Part Number Description Qty
12563240 Assembly, Engine Oil Pan 1
24502397 Gasket, Engine Oil Pan 1
12346286 Sealant, 5900 RTV, 5 oz. (142 ml) 1
12346139 (10953463 in Canada) Solvent, Aerosol Spray 1


Parts are currently available from GMSPO.


GM bulletins are intended for use by professional technicians, NOT a "do-it-yourselfer". They are written to inform these 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 your GM dealer for information on whether your vehicle may benefit from the information.


© Copyright General Motors Corporation. All Rights Reserved.