Oil Pump Replacement

[Scott21]

It looks simple on my 52. Any tricks to it?

Scott

[wesk]

Just follow the steps in the book, remember it drives your distributor, and prime it.

[skyjeep50]

I removed the oil pump from my M38A1 to check for blockage. Had a devil of a time getting it back in. When inserted the gears tend to turn the oil pump shaft slightly misaligning the keyway that drives the distributor. You can use a mirror to line things up before inserting the pump shaft but I just couldn't keep the alignment from changing. Got frustrated, left it for a couple of days, went back and tried again, blew it again and left it a couple more days, etc. Called a mechancally minded friend and he tried with the same results but finally he got it to click into place after about 45 min of fiddling. If the pump did not have to be primed it would be simple to take off the pump cover and rotate the gears to align the shaft. Anyone got a tip to prevent the shaft from turning??

[wesk]

When you are trying to engage two helical cut gears you cannot push it straight in. You must rotate the shaft backwards a bit to lead the engagement of the gears so as it is forced to turn forward it will end up where you want it. If you leave the distributor firmly bolted down it will make all of this twice as hard. The engine manual explains in great detail how to properly position the oil pump with the distributor remove so the distributor will be correctly oriented when you install it.

[skyjeep50]

That was definately the problem. We tried to lead the pump shaft but to get it to engage, we found you have to be right on. I didn't want to loosen the distributor for fear of loosing the right position and messing up the timing. I suppose marking the position would help get the distributor lined up again. Live and learn!
Thanks Wes!