292 Oil Pressure

[Short 3/4]

What is the preferred range of oil pressure in this engine? I tried looking it up in the factory book, but couldn’t find any numbers. It’s (I think) a ‘68 block, and was professionally rebuilt about 6 years ago. It’s now got about 25K on it.

My problem is one I’ve never heard of before. Instead of the oil pressure getting lower over time it’s getting higher ??!! It’s always been good, between 20 and 60 PSI, but lately it’s been between 50 and 80 (has a good aftermarket mechanical gauge). Not sure what kind of pump the shop put in, and I can’t figure out if the pressure is adjustable on this engine. Was pumping out a lot of oil yesterday (on the ground). I tightened up all the admittedly loose covers, and hopefully the rear main didn’t get blown out, but I’m reluctant to drive it until I can figure out what’s going on.

Thanks for any help,
Tom

[Short 3/4]

Forgot to mention, I run 10-30W oil and Wix brand filters. The weather is also very mild where I live so cold is not an issue.

Hope this helps

[AussieinNC]

Originally Posted by Short 3/4

Forgot to mention, I run 10-30W oil and Wix brand filters. The weather is also very mild where I live so cold is not an issue.

Hope this helps

Sounds like the pressure relief valve in the oil pump is stuck closed and not regulating oil pressure.

I would be concerned the drive to the oil pump may shear off in time as the system is not designed for that level of pressure.

Any chance you could ask the shop that built the engine what pump is in the engine?

[Short 3/4]

Just talked to my engine builder. While it’s been about 6 years, he’s pretty sure he put in a high pressure pump since it’s a 4x4 and still used for hauling and off-road duty. His opinion is to not worry about anything under 100 pounds. I’ve been using him for many decades, including the last rebuild of this 292 back in ‘93, so I obviously trust him, but still always open to other’s opinions

[AussieinNC]

My prime concern would be excessive wear on the distributor drive as it takes more effort to turn the oil pump.

Time will tell I imagine.

[RustyPile]

Even though you trust your "aftermarket" gauge, it's always a good idea to "get a 2nd opinion".. Obtain another quality gauge and compare that gauge's reading to the one you're using now.. If the readings coincide, you probably have issues with the pump or other items. If the readings don't coincide, you have a gauge issue... Either way, the symptoms should NOT be ignored..

[Short 3/4]

Thanks for all the input. Can especially appreciate the advice to double check the gauge (I once spent a lot of time trying to “fix” an overheating problem that turned out to be a bad gauge…embarrassing!).

Going back to the original question though, does anyone know the factory recommended pressure readings? Hot / cold, idle / high speed? The factory gauge only goes to 60# so figure it’s not more than that. Handbook says needle may peg on cold start and to not drive away until it goes to about half scale. 30#, at idle?

Anyway, would be interested in what Chevy had to say about this. Someone out there must know.

Thanks
Tom