Oil Pressure Testing Buick Century VI

Tools Required

J25087-C Oil Pressure Tester. See Special Tools and Equipment .

If the vehicle has low oil pressure complete the following steps

1. Inspect the oil level.
2. Raise and support the vehicle. Refer to «LIFTING AND JACKING THE VEHICLE»(ref-189331-S23727654502005090900000) in General Information.
3. Remove the oil filter.
4. Assemble the plunger valve in the large hole of the J 25087-C base. Insert the hose in the small hole of the J 25087-C base. Connect the gauge to the end of the hose.
5. Insert the flat side of the rubber plug in the bypass valve without depressing the bypass valve.
6. Install the J 25087-C on the filter mounting pad.
7. Start the engine.
8. Inspect the overall oil pressure, the oil pressure switch, and for noisy lifters. Ensure that the engine is at operating temperature before inspecting the oil pressure. The oil pressure should be approximately 414 kPa (60 psi) at 1,850 RPM using 5W-30 engine oil.
9. If adequate oil pressure is indicated, test the oil pressure switch.
10. If a low reading is indicated, press the valve on the tester base in order to isolate the oil pump and/or its components from the lubricating system. An adequate reading at this time indicates a good pump and the previous low pressure was due to worn bearings, etc. A low reading while pressing the valve indicates a faulty pump.