OIL LEAK AT FRONT CRANK SEAL NEW FRONT CRANKSHAFT SEAL. GMC Truck S15 Pickup - 2WD 1991

For 1990-2009 cars

# OIL LEAK AT FRONT CRANK SEAL NEW FRONT CRANKSHAFT SEAL

#### SUBJECT: OIL, LEAK AT FRONT CRANKSHAFT SEAL (NEW SEAL W/LOCTITE)

#### VEHICLES AFFECTED: 1990 4.3L C/K/G/P/M/L AND 1991 4.3L S AND T TRUCKS

#### CONDITION

Some of the above Trucks may exhibit an oil leak at the front of the engine coming from between the crankshaft seal and timing chain cover.

#### CAUSE:

------- This condition may be caused by inadequate retention of the crankshaft seal in the timing chain cover.

#### CORRECTION:

------------ To correct this condition a new front crankshaft seal must be installed per the following instructions.

1. Remove old seal per Service Manual section 6A.

2. Thoroughly clean the hole in the timing cover and metal outside diameter of the new seal. Wipe both surfaces using a clean rag damp with brake cleaner solvent, isopropyl (rubbing) alcohol or Loctite (R) 755 cleaning solvent.

#### IMPORTANT: Do not use gasoline, diesel fuel, kerosene, or solvents which may leave a residue or deteriorate the seal.

3. Inspect cover hole for any damage. If damage is apparent replace cover assembly. If there is no damage continue to Step 4.

4. Apply a bead of Loctite (R) 680 retaining compound around the metal outside diameter of the new seal and install the seal per the service manual using tool J-35468.

#### IMPORTANT: Do not use RTV in place of Loctite (R) 680 to install the new seal.

#### SERVICE PARTS:

Description P/N ------------------------- ------------------ Seal, Crankshaft Front 10111769 Loctite (R) 680 Retaining Compound Obtain from local Loctite Distributor

Loctite (R) 755 Cleaning Solvent Obtain from local Loctite Distributor

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