Low oil pressure in a 292

[Guest Guest]

Hello again,

Well I think I already know the answer to the question, but it doesn't hurt to ask.

The old 65 Chevy 292 has about no oil pressure to speak of, the gauge shows just over 20 psi when cold and maybe 5 psi @ idle once it warms up. No, its not being driven at all.

There doesn't seem to be any rod, or main bearing noise such as knocking, and the engine doesn't smoke or show other signs that its just flat worn out. In fact, with the exception of the low oil pressure the engine runs very well.

However, there is a noise coming from the bottom of the engine that sounds like it could be being made by the oil pump.

My questions are, has anyone ever run across, or heard of a Chevy 292 with a weak, or worn oil pump that was the lone cause of low oil pressure? And, could a stuck check valve cause low pressure?

I have no history on the engine other than hearsay that the engine was rebuilt at some point. ( this is an old commercial truck, it very well may have been rebuild more than once )

And one last thing, it sat for many years ( maybe as many as 8 years ) with filthy oil in it, could this have any effect on the pump?

Thank you so much for any advise or theories.

[Guest oldbill]

The rod/main bearing clearance is too wide, probably from wear. Pull off the pan and plastic guage a few bearings.

[Guest Guest]

Yup, I was thinking the same thing. I just had a problem with the lack of bearing noise, IE. no rod knock. I'm wondering if maybe the cam bearings are the problem seeing how there's nothing knocking.

Oh well, guess I'll just have to drop the pan one of these days and have a little look see around in there.

Thank you for the reply.

[Guest Jim_Edwards]

Yup, I was thinking the same thing. I just had a problem with the lack of bearing noise, IE. no rod knock. I'm wondering if maybe the cam bearings are the problem seeing how there's nothing knocking.

Oh well, guess I'll just have to drop the pan one of these days and have a little look see around in there.

Thank you for the reply.

Hopefully you'll be lucky and will have caught the bearing problem before it has made a mess out of the crankshaft. By the time a rod knock is heard it may be basically over for the crank. Bummer!

Jim

[Guest Guest]

Well...it was a bring me up and let me down kinda day.

The elusive exhaust leak in the manifold has been found and sealed. The engine is now very quiet, so quiet that I can now hear the rods rattling.

So yet another project for the endless list of repairs.

Thanks for the tips.

[rjengelhart]

Can the bearings be replaced by dropping the pan or must the engine be torn down?

[Beltfed]

I don't know if this is 'kosher' but you should ask your question over on the "Stovebolt" forum under engines. This is where old Chevy stovebolters hang out. Your engine is one of those. Very active forum. They have a love/lust for the 292 which is the big dog in Chevy straight sixes.