NO/LOW ENG. OIL PRESS AFTER STARTER, COLD ENGINE

MODELS AFFECTED: 1988 SKYLARKS WITH 2.3L ENGINE (VIN CODE D)

CONDITION:

Some 1988 Skylarks equipped with a 2.3L Quad 4 engine may experience a momentary no or low oil pressure condition when first started after a cold soak at or below freezing.

CAUSE:

This condition can result from condensed crankcase water vapor icing over the bottom of the oil pump screen assembly.

CORRECTION:

To correct this condition, a 1/4 inch hole can be drilled into the side of the screen assembly pick up as described in the following service procedure. This hole will allow oil to be drawn into the oil pump should the bottom of the screen assembly ice over.

SERVICE PROCEDURE:

Refer to Section 6A7, in the 1988 Skylark Service Manual when performing the following service procedure.

1. Drain engine oil and remove oil pan.

2. Remove two (2) screws attaching screen assembly to oil pump and one (1) nut attaching screen assembly to block.

3. Remove screen assembly and thoroughly wash off all oil and dry.

4. Locate and mark position for 1/4 inch hole to be drilled on side of screen assembly pick up. Refer to Figure 1.

5. Clamp screen assembly pipe in a bench vise being careful not to bend or distort the pipe.

6. Drill a 1/8 inch pilot hole at location marked in Step 4. After drilling pilot hole, use a 1/4 inch drill bit and drill hole to 1/4 inch.

7. After drilling, thoroughly deburr hole.

IMPORTANT

8. COMPLETELY REMOVE ANY METAL SHAVINGS FROM SCREEN ASSEMBLY AND THOROUGHLY WASH OUT ASSEMBLY WITH CLEAN SOLVENT.

9. Thoroughly wash out oil pan and dry.

10. Install new screen assembly to oil pump gasket, part number 22532023.

11. Install screen assembly to oil pump.

12. Install and tighten two (2) screen assembly to pump screws to 12 N.m (106 lbs. in.)

13. Install and tighten screen assembly to block nut to 26 N.m (19 lbs. ft.)

14. Install oil pan using new pan gasket.

15. Refill engine with fresh engine oil.

16. Remove oil pressure switch/sensor from end of exhaust cam carrier and install an accurate engine oil pressure gage.

17. Start engine and observe oil pressure. Minimum pressure, cold engine: 40 psi.

18. Remove oil pressure gage and install switch/sensor.

19. Inspect for oil leaks.

Parts are currently available from GMSPO.

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.