Oil pump rebuild with Billet Gears...mmmm.shiny
 

First part of my engine rebuild. Finally broken down the engine and with my new oil pump gears on their way from boundary I figured I would check out the oil pump.

The first thing I notice when I pull the pump from the crank nose is that one of the screws holding the back plate on was loose and had unwound a few turns. In fact 3 of the screws were finger tight but the rest were locked in properly.

Then having pulled the gears I notice this scoring in the housing.

Attachment 201204

I haven't got measured the clearances yet because I need to get my feeler gauges back from a friend who should have returned them a while ago :facepalm: But before I pulled the engine I had reasonable oil pressure, not great but OK. Is this kind of wear to be expected from a 70k oil pump or is it fatal and would be a waste to rebuild it? They are definitely grooves that you can feel with a finger nail but I wouldn't say "catch a nail on".

Whaddya think peeps?

im not sure but i have a brand new mellen oil pump ill sell for 70 shipped if needed., i bought a built pump from boundary so now i dont need this one nm shipping would probably be to much..

No one care to chime in on this? Travis?

I checked the clearances with molestation gauges and all is well. The max endplay for the gears in the housing is .0055" and I'm at about .0035" and I doubt those scratches are more than 2 thou deep so I'm gonna roll with it for now unless anyone can tell me I'm going to grenade my motor in 2 miles by doing so.

I may lap the housing on a surface table to get the endplay down to around 2 thou.

Anyone have any info on shimming the pressure relief valve for more pressure or am I wasting my time with this notion?

I'd suggest emailing travis directly. He's not on this or the other forums that much.

thats kinda what mine looked like. i dropped them in and went with it as i was on a tight schedule. all is well so far.

They should be fine, the scratches aren't really deep. It wouldn't hurt to stick a plastigauge in there and see though. Just make sure everything is super clean when you reassemble the motor. Whatever is in there has already worked on some of the wear surfaces of the engine, and its important to make sure all the oil passages and all the surfaces are purged really well. The more marks like that there are, the more likely it is that you could have pieces of metal lodged in tight spots of the engine.