SERVICE MANUAL UPDATE-SEC.6 ENGINE OIL PRESSURE CHECK

Model and Year: 1990 R CAR

This bulletin is an addition to Section 6 of the 1990 GEO Storm Service Manual.

1. Check the engine oil level. Oil should be visible on the dipstick between the "ADD" and the "FULL" marks. If oil is not visible past the "ADD" mark, add API Service SG SAE 5W-30 (SOHC) or API Service SG SAE 10W-30 (DOHC) engine oil until oil is visible on the dipstick past the "ADD" mark.

2. Remove the oil pressure sending unit. The sending unit is located on the right-hand side of the engine block, just left of the starter.

3. Screw a J 25695-10 adapter into the engine block where the oil pressure sending unit was removed. Install a J 21867 Pressure Gage to the adapter.

4. Start and run the engine until operating temperature is attained.

5. Increase engine speed to 3,000 RPM and measure oil pressure. Oil pressure should be 300 to 500 kPa (43.5 to 72.5 psi) at 3,000 RPM (SOHC) or 350 to 550 kPa (51.2 to 80.4 psi) at 3,000 RPM (DOHC).

6. Stop the engine.

7. If oil pressure does not fall within the above specified limits, refer to "Low Oil Pressure" in this section for further diagnostic information.

8. Remove the J 21867 Pressure Gage and the J 25695-10 adapter from the engine block.

9. Install the oil pressure sending unit.

10. Restart the engine and check for oil leaks.

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.