L29 MPI Gen VI low oil pressure
 

Just looking to get a core for my rebuild. Found an L-29 MPI complete with exh man, sans intake. Well priced, but owner said it had low oil pressure at 10psi. No knock sounds etc. This sounds like a broken relief spring issue or something like that?

I just want to make sure the block is good to go...and no spun bearings...my spun bearing experience...I still had good oil pressure.
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Thanks,

Art

If your rebuilding why worry about low oil pressure, oil pump gets replaced, bypass valves, bearings, crank turned, etc

Just wanted to make sure the block would be ok.

Probably a broken broken oil pump relief spring?

Most likely either a bad gauge or things are worn out (bearings and such)

If motor runs it's all good. If it rotates by hand then it's not locked up
If you think block might be cracked, do pressure test.

Low oil pressure would not give me any concern if I was rebuilding

Does the engine have an oil filter on it ? If so take it and get it cut open and see if there is any bearing material or other metal in it. In my 36 years of owning a machine shop it has been very very rare that an engine with low oil pressure did not have some type of serious damage.

Very good point...getting info on it would be beneficial for sure.
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I need a good filter cutter.

600 ish hours on it.

I'll put the drill on the oil pump and have a look as well, before tearing it down.

Is the core a marine engine ? Too bad you are not close by, I have a real nice complete L29 truck engine I wouldnt mind getting rid of :(

Your 'broken" oil pump relief spring is wishful thinking. Ive seen a few bypass balls/plungers in them stuck with debris a couple times BUT for most part like Bill K said, the "bad" oil pump in a engine is usually NOT the root cause off low oil pressure, Smitty

Is it being sold as a core?
Is it priced as such?
Flip it over before you hand over the cash and remove the pan.
Rattle the rods, remove the mains.

If the guy is asking above core value or won't let you do that, I'd move on.
I can't speak for you or anyone else, but that's what I'd do.
No wishful thinking involved.

Yeah...core value...and better. $150 for the complete L29 Marine including the exhaust manifolds.
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No MPI Intake. I need the block only.
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No risk really. Lots of things to sell to make up for the effort and time if it turns out the mains are spun ir something like that.