So I've decided to rebuild an oil pump on my son's 86'Brat. Oil pressure is 45psi dead cold idle/ and 70psi on cold 2k rpm. Hot idle at 800rpm is 12psi and 20 psi at hot 2k rpm. I would just replace the pump or internals if I could find one. Anyone have any suggestions on parts location. Google has kinda failed me. On a side note the cheap oil pressure sender is correct and the gauge is showing about right. Just kinda low oil pressure. Oh yeah, I pulled the oil pan to replace the gasket and found nasty metal sludge in there. Dang!

If there's metal in the pan, there's no reason to do anything with the oil pump. You can get a seal kit at the dealer. 

Oil pumps don't produce "pressure", they produce flow, and the volume of that flow in conjunction with the restriction to that flow provided by the clearances in the engine creates the pressure. Since it is unlikely that the pump's volume has been reduced significantly (unless it's wrecked inside which doesn't seem to be the case based on the cold pressure readings),  that leaves the clearances in the engine are likely shot. 

There's no purpose in replacing or rebuilding the oil pump if the engine is hosed internally. Any metal that you can see with the naked eye is bad.

And yes - the oil pumps for the EA engines are discontinued. No one can get them. The only source was Subaru and they stopped being interested in making them. 

GD

Thanks Bud. It was leaking too. Sounds like a reseal and run it. It did look nasty in the oil pan. So I'm just gonna run it till it doesn't any more.

Sooo..... pump disassembled it looks like crap. Pump shaft is damaged and housing it done. Had a rough looking engine that came with the Brat. Removed it and it looks great. Even though the engine looks terrible. The pump is top notch. Will report new pressure readings when installed.

You are starting to make me think I should pull the preserved in grot pump from "my" barn find.

A mate has finally released it 30 months after I showed interest in bits for export

Like anyone with 70-odd cars, he had an attachment to this bucket of rust and took something like a car stashed deeper than it that he wanted out, before I could get at it.

He packs them in like sardines in a tin

9/84 compliance plate EA81 Sportswagon

478,000 km on the odo. Pretty amazing the odo has counted this far. Never had one wind up thistle much

Has black rocker covers so may be later engine in it.

Now, to your oil pressure query

I guess cold readings are not what anyone is chasing, but worth noting for those that ask. And with our old girls maybe they should be warned up a bit so not to pop oil pressure things ?

What I have read is that at op temp, ~ 10 psi per thousand revs in normal driving is found

20 psi at 2000 rpm about normal ?

Are you going to check its feeler gauge specs?

Edited July 21, 20205 yr by Step-a-toe

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Is an oil pump assy part number but for what ?

Sounds EA82 or ER27??

Yeah, I couldn't find one for sell. Though the operating temp oil pressure was at minimum acceptable spec. I decided to inspect it anyways. Glad I did cause it looked terrible. I'm sure the internal engine clearance is worn as well and oil pressure is never gonna be high. But that pump was about to crap out and seize up. I'd hold on to that pump if I were you. They seem rare now. I'll post new pressure readings tonight.

Ending oil pressure is 12psi hot idle and 22 psi 2k rpm. Confirmed internal engine wear is the cause of low pressure. Just drive it till it quits

If the pump looks like that, then the rest of the engine is likely not far behind it. Putting a really nice pump on there is a great way to destroy the good pump when it encounters all the metal from the engine. The pump isn't going to help the situation. 

GD

Yup. Drove around for about 2hrs last night. It gets down the road alright for an old barn find.

I pulled the filthy dirt and oil encrusted pump yesterday 

Trying my best to keep self clean and housing in one piece 

I can see score marks on one face of the rotating pieces so likely garbage but maybe the housing still worth looking at