Engine - Smoky Exhaust/Oil Consumption: Overview
NO.: 09-18-92 Rev. AGROUP: Engine
DATE: Jan. 13, 1993
SUBJECT:
Excessive Oil Consumption 3.0L MMC Engine
THIS BULLETIN SUPERSEDES TECHNICAL SERVICE BULLETIN 09-18-92 WHICH SHOULD BE REMOVED FROM YOUR FILES.
MODELS:
1989 - 1993 (AA) Spirit/Acclaim/LeBaron Sedan
1989 - 1993 (AC) Dynasty/New Yorker/New Yorker Salon/New Yorker Landau
1990 - 1993 (AG) Daytona
1990 - 1993 (AJ) LeBaron Coupe/Lebaron Convertible
1992 - 1993 (AP) Shadow/Shadow Convertible/Sundance
1987 - 1993 (AS) Caravan/Grand Caravan/Caravan CV
Voyager/Grand Voyager/Town & Country
1990 - 1991 (AQ) Chrysler TC
1988 (C) Dynasty/New Yorker
DISCUSSION:
Engines built since 11/15/91 (build code BDL7.067) have snap rings installed on the exhaust valve guides. Engines built since 10/2/92 (build code BDL7.416) have improved intake and exhaust valve stem seals in addition to the snap rings on the exhaust valve guides. The build code label is located on the intake plenum.
SYMPTOM/CONDITION:
Observed oil smoke in the exhaust at idle or during deceleration (conditions causing high intake manifold vacuum. Excessive oil consumption is more than one quart per 1,000 miles on vehicles with less than 50,000 miles or more than one quart per 750 miles on vehicles with more than 50,000 miles.
DIAGNOSIS:
Verify the PCV system is functioning properly and engine compression is within specifications. Refer to the appropriate technical service manual for test procedures and specifications. If the PCV system and engine compression are within specification, perform the repair procedure.
PARTS REQUIRED:
SPECIAL TOOLS REQUIRED:
REPAIR PROCEDURE:
This bulletin involves installing snap rings on the exhaust valve guides and replacing all of the valve stem seals or cylinder head replacement as determined by inspection.
1. Remove the intake plenum and manifold.
2. Remove the rocker cover, rocker shaft and cam bearing cap assembly on the forward bank using the procedure in the appropriate technical service manual.
3. Remove one of the cam journal caps from the assembly and reinstall on the head. This will prevent the cam from possibly coming out of the journals when the engine is rotated later.
4. Check front bank cylinders in # 4, # 2, then # 6 sequence.
NOTE:
IF A VALVE GUIDE CAN BE MOVED WITH FINGER PRESSURE, REPLACE THE CYLINDER HEAD.
5. Remove the spark plug and apply compressed air to the cylinder to prevent valve dropping. Use special tool MD998772A to remove the intake and exhaust valve locks, the valve spring retainer, valve spring and valve spring seat.
6. Remove the valve stem seals.
7. Using the height gauge that is integrated into the Groove Cutter (Special tool MD998790), measure the distance between the top of the exhaust valve guide and the top of the valve guide boss on the cylinder head (refer to illustrations of Fig. 1). If the distance is .335" (8.5 mm) or less the cylinder head will have to be removed for repair, perform PROCEDURE B. If the distance is .335" (8.5 mm) or more, perform PROCEDURE A.
8. Repeat steps 2 through 7 for the rear bank. Do the cylinders in # 3, # 1, and # 5 sequence.