Skylark L4-138 2.3L DOHC VIN D MFI QUAD 4 (1989)
7.
Clean each head bolt seat boss on the cylinder head. Clean the bolt holes in the cylinder block. DO NOT USE A TAP TO CLEAN THE HOLES.
8.
Replace the oil flow check valve in 1988 through 1989 model year vehicles. Refer to the applicable 1991 model year service manual. The check
valve does not need to be replaced in 1990 or newer vehicles or those vehicles where the check valve had been previously replaced.
NOTICE:
To determine if the check valve has been previously replaced on 1988 through 1989 vehicles, shine a flashlight into the oil check valve. If there
are three dimples immediately above the check ball, it is the new style oil flow valve and should not be replaced (see Figure 3).
9.
Apply clean engine oil to the threads and the bottom side of the flange of the head bolts (see Figure 4).
NOTICE:
The following head bolt tightening procedure must be used to assure gasket life. Failure to follow this procedure exactly may result in cylinder
head gasket leakage. All TEN bolts must be torqued in Steps 10 & 12 BEFORE the angle turn is applied in Steps 11 and 13.
PRE-CONDITION THE CYLINDER HEAD GASKET - STEPS 10 AND 11.
