2001 Subaru Forester BaseFACTORY OEM SERVICE PROCEDURE

Oil Pump Assembly: Inspection

  1. Check seal ring and O-ring oil seal for breaks or damage.
  2. Check other parts for dents or abnormalities.
  3. Selection of oil pump rotor assembly
    1. Tip clearance

      Install inner rotor and outer rotor to oil pump. With rotor gears facing each other, measure crest-to-crest clearance.

      Tip clearance:Β  0.02 - 0.15 mm (0.0008 - 0.0059 in)

      Fig 1: Measuring Crest To Crest Clearance
      G02003344
    2. Side clearance

      Set a depth gauge to oil pump housing, then measure oil pump housing-to-rotor clearances.

      Side clearance:Β  0.02 - 0.04 mm (0.0008 - 0.0016 in)

      Fig 2: Measuring Oil Pump Housing To Rotor Clearances
      G02003345
    3. If depth and/or side clearances are outside specifications, replace rotor assembly.
      Fig 3: Oil Pump Rotor Assembly Specifications
      G02003346
Factory Service Tools

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When to See a Mechanic

Stop DIY work and contact a certified mechanic immediately if any of the following apply:

  • β€’ You smell fuel, burning insulation, or see smoke.
  • β€’ Brakes feel soft, pull hard to one side, or make grinding noises.
  • β€’ The engine overheats, stalls repeatedly, or misfires under load.
  • β€’ You are missing required tools, torque specs, or safe lifting equipment.
  • β€’ You are not confident in the next step or safety outcome.