jb451

This is in my 3.4 swapped '90 (1998 4runner 5vze if it matters)-

Last year after my swap I started having a squeaking noise from the front of my engine, after progressively getting worse diagnosis turned up a squeaky oil pump. Ordered a new aisin pump off of rock auto and installed, squeaking noise went away and then came back even worse a week later in the form of a scream now. Noise is most prevalent at sub 1300rpms on cold starts. Anything above 2k and it goes away. Was going to try running rotella or delo but with it being cold i dont want a spun bearing.

I'm thinking one of two things-
I should have torn it apart and pre lubed it (pamplet in box said nothing about this and I cranked the engine over before starting to get oil in it)
Thrust bearing/washer toast, causing the front and rear of pump rotor (in respect to the engine), to rub against pump housing. The old oil pump had wear marks against the rear of pump, which i thought was where the original problem originated.

At this point i need to put new rings in this engine anyway, so i might just get/build a new engine but i'd like thoughts/opinions on what this issue might be.

Thanks fellas.

fierohink

It sounds like you have some wander in your crank. This is causing the pump to get pushed in the housing as well as the Pistons to move in the bores wrecking your rings or cylinder walls.

And remember you're talking thousandths of an inch of play here. So it would be almost unidentifiable without micrometers.

jb451

That would make sense given the ring issues... Bought the engine off a junkyard shelf, possible it was in a front end wreck and shoved the crank rearward? Hopefully the bores are saveable.