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I scored an oil pump rebuild kit a while back for next to nothing and i was curious if anyone had used one? Ive rebuilt pumps before for John Deere stuff. The old pump made plenty of pressure and is in good shape but is a civilian pump so the key way is not offset. Any experience with these kits, the parts are in perfect shape and the TM has specs for rebuilding them.

guess not

Yes we have built oil pumps. Seldom do we see one that does not measure up within specs, check the engine build manual for those numbers and checking procedure. The most common thing we see in oil pumps is scoring on the interior side of the cover plate. Take the plate to a local machinist that has a finishing surface grinder and get them to dress it back flat, takes 5 minutes or less. This will remove any end play that has become an issue. Hardly ever do we see a shaft, vane/rotor assembly that has any significant wear. I have even measured up new pumps right beside used ones for comparision. More than once I've found new pumps that were a looser fit in the vane/rotor assembly than the used one I was comparing it too. Removing the scoring from the cover plate most often restores a pump to very good condition.

awesome. I so happen to have access to a full machine shop for free. Ill build a jig and deck the top cover with a fly cutter on the mill. Ought to be plenty flat enough! Thanks for the advice Charles!

98taco3 wrote:awesome. I so happen to have access to a full machine shop for free. Ill build a jig and deck the top cover with a fly cutter on the mill. Ought to be plenty flat enough! Thanks for the advice Charles!

I would surface grind as a first choice or blanchard grind as second choice before I would Fly cut the cover. You will get a better microfinish. Just my two cents.

T. Highway wrote:

98taco3 wrote:awesome. I so happen to have access to a full machine shop for free. Ill build a jig and deck the top cover with a fly cutter on the mill. Ought to be plenty flat enough! Thanks for the advice Charles!

I would surface grind as a first choice or blanchard grind as second choice before I would Fly cut the cover. You will get a better microfinish. Just my two cents.

I agree, it should be the best finish possible. I use a shop that does precision tool making.

hmmm ok. I was thinking about running a fly cutter over it and hand lapping it on a piece of glass like you would a fuel injector. Ill look into finding a shop with grinding capabilities

98taco3 wrote:hmmm ok. I was thinking about running a fly cutter over it and hand lapping it on a piece of glass like you would a fuel injector. Ill look into finding a shop with grinding capabilities

Grinding is much more precise than anything you could ever accomplish by hand. The fact it may just look flat doesn't say much; it needs to be precisely flat. I always have them dress both sides of the plate, this way we are assured it has a perfectly flat surface to lay on the magnetic table, and the interior side is then dressed perfect.