im rebuilding my engine at the moment and i would like to check over the oil pump before i refit to see if its within spec. I have had a look throught my manual and cannot find any information on it .
What parts do you measure and what are the tolerances???

cheers

Russell

 

I do have it here somewhere. Once you have it apart, you're looking mainly at the interlocking pump gears under the cover. The info is on page 378/379 of the 2002 Impreza workshop manual which can be downloaded from a few places.

It's a bit hard to describe without pictures but you need to measure tip clearance (between where the gears mesh) - 0.04-0.14mm; case clearance (between the outer edge of the outer rotor and the pump casting) - 0.10 - 0.175mm; side clearance (between the gears and the underside of the cover when you fit it down - measure by putting a straightedge across and slipping in a feeler gauge) - 0.02 - 0.07mm. The gear cover needs to be tightened down at 5Nm and the plunger plug at 44Nm.