LEMON Manuals: Even more car manuals for everyone
Home >> GMC >> 2003 >> Safari Van Cargo, AWD >> Repair and Diagnosis >> External Pages >> Different car >> Section 1255 (Engine Mechanical - 3.1L Unit Repair) >> Repair Instructions >> Oil Pump Cleaning and Inspection

Oil Pump Cleaning and Inspection

WARNING: This page is about a different car, the 2002 Pontiac Grand Prix. However, it is still accessible from the selected car via links, so may be relevant.
CAUTION: Bodily injury may occur if the cleaning solvent is inhaled or exposed to the skin.
  1. Clean all parts of sludge, oil, and varnish by soaking in cleaning solvent.
  2. Inspect for foreign material and determine the source of the foreign material.
  3. Inspect the pump housing and cover for the following conditions:
    • Cracks or casting imperfections
    • Scoring (3)
    • Damaged threads
  4. Do not attempt to repair the pump housing. Replace the pump housing.
  5. Inspect the oil pump gears for the following conditions:
    • Scoring (1)
    • Excessive wear (2)
  6. Inspect the idler shaft for looseness or scoring (4). If loose or damaged, replace the oil pump.
  7. Inspect the drive gear shaft for looseness or scoring (5).
    Fig 1: Inspecting Oil Pump Components
    G01702921Courtesy of GENERAL MOTORS CORP.
  8. Inspect the pressure regulator valve for the following conditions:
    • Scoring
    • Sticking
    • Burrs may be removed using a fine oil stone.
  9. Inspect the pressure regulator valve spring for the following conditions:
    • Loss of tension
    • Bending
  10. Inspect the suction pipe and screen assembly for the following conditions:
    • Looseness
    • If the suction pipe is loose, bent or has been removed, replace the pump body cover and suction pipe.
    • Broken wire mesh or screen
      Fig 2: Inspecting Oil Pressure Relief Valve
      G01702922Courtesy of GENERAL MOTORS CORP.
  11. Measure the oil pump gear lash. Install the gears, and measure in several places.
    Fig 3: Measuring Oil Pump Gear Lash
    G01702923Courtesy of GENERAL MOTORS CORP.
  12. Measure the oil pump housing gear pocket (1, 2).
    Fig 4: Measuring Oil Pump Housing Gear Pocket
    G01702924Courtesy of GENERAL MOTORS CORP.
  13. Measure the oil pump gears (1, 2).
    Fig 5: Measuring Oil Pump Gears
    G01702925Courtesy of GENERAL MOTORS CORP.
    IMPORTANT: When deciding pump serviceability based on end clearance, consider depth of the wear pattern in the pump cover.
  14. Measure the oil pump gear side clearance.
    Fig 6: Measuring Oil Pump Gear Side Clearance
    G01702926Courtesy of GENERAL MOTORS CORP.
scientia non olet · About LEMON Manuals