Oil Pump Inspection

TOOLS REQUIRED:  SA91101NE Feeler Gauge Set

1. Inspect body clearance:
   1. Using a feeler gauge Service Tool SA91101NE (or equivalent), measure the clearance between the driven rotor and pump body.

      Body to Side Clearance 

      Standard: 0.150-0.277 mm (0.006-0.011 in.) 

      Service Limit: 0.277 mm (0.011 in.) max. 

      Fig 1: Measuring Clearance Between Driven Rotor And Pump Body

      Courtesy of GENERAL MOTORS CORP.
   2. If the clearance is greater than maximum, replace the oil pump rotor set.
2. Inspect tip clearance:

   Using a Feeler Gauge Set SA91101NE (or equivalent), measure the clearance between both rotor tips.

   Clearance 

   Standard: 0.150 mm (0.006 in.) max. 

   Fig 2: Measuring The Clearance Between Both Rotor Tips

   Courtesy of GENERAL MOTORS CORP.
3. Inspect end-to-end clearance:

Using a Feeler Gauge Set SA91101NE (or equivalent) or Plastigage(R) (or equivalent) measure the clearance between the side of the gerotor assembly and the cover plate.

End-to-End Clearance 

Standard: 0.040-0.125 mm (0.0016-0.0049 in.) 

Service Limit: 0.128 mm (0.005 in.) max. 

Fig 3: Measuring The Clearance Between The Side Of The Gerotor Assembly And The Cover Plate

Courtesy of GENERAL MOTORS CORP.