OIL LEAK AT OIL FILTER ADAPTER (REPLACE SEAL)

SUBJECT: OIL LEAK AT OIL FILTER ADAPTER (REPLACE SEAL)

VEHICLES AFFECTED: 1993 "E", "K", "V" MODELS WITH 4.6L (VIN CODES 9 OR Y - RPOS L37 AND LD8)

Some 1993 Eldorados, Sevilles, or ALLANTES equipped with 4.6L Northstar powertrain system may experience oil leakage in the area of the engine oil filter. Since there are multiple areas of potential leakage (i.e., filter, pressure switch, cooler lines, adapter) careful diagnosis must be made to assure the actual leak is addressed. New vehicles especially may appear to exhibit a leak which may in fact be residual oil from the assembly process which has accumulated near this area. Proper diagnosis would include thoroughly washing the area with fabric cleaner and running the engine to confirm the exact leak.

When diagnosis indicates the leak is between the oil filter adapter and the lower crankcase, proceed as follows:

1. Remove the oil filter adapter as described in Section 6A of the preliminary information manual.

2. Inspect the oil filter adapter casting for damage. Look particularly at the following areas.

a) The boss for the hex plug on the side of the adapter.

b) The bosses for the oil cooler line connections.

c) The boss for the oil pressure switch.

3. If the adapter is undamaged, proceed as follows to replace the adapter 0-rings. Refer to Figure 1 for proper selection of parts.

a) Vehicles using filter adapter with casting number 3543718 may proceed to step 4.

b) Vehicles using filter adapter with Gasting number 3538849 proceed as follows.

c) Eliminate any sharp edge on the oil holes in the crankcase by lightly chamfering the inside diameter edge with emery cloth. It is unnecessary and undesirable to create an actual chamfer; merely dress down whatever sharp edge exists.

d) Clean sanded area with fabric cleaner.

4. Install new 0-rings to adapter. Use 0-ring 3543719 with adapter 3543718 and 0-ring 3543024 with adapter 3538849. Petrolatum may be used to retain the 0-rings. Refer to Figure 1 for correct parts identification.

5. Install adapter as described in preliminary information manual. Over tightening will not increase the sealing ability of O-ringed joints. Tighten adapter bolts to 25 N.m (20lbs.ft) and cooler lines to 18 N.m (12lbs.ft). If 0-rings do not seal at these torques, find the source of the problem.

For vehicles repaired under warranty use:

Labor Time: .7 Hours

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.