The Stovebolt Site Forums The Shop Area Engine Shop Engine Oil Pressure after Rebuild

Need to know if I have a problem here, shipmates.

I put a freshly rebuilt 283 into my 58 Chevy Apache (special thanks to all who offered advice but especially HotRod Lincoln & Wrenchbender for leading me along the path to initial startup & self-sustaining internal combustion).

The girl is starting & running pretty well. The short distance between running pretty well and running fine will be traversed when I tweak the timing in.

I was watching my gauges during this initial start up and run in and I seem to have an abundance of oil pressure. I start her up. The oil pressure comes up smoothly & goes right up to about 60 PSI.

This seems a bit high to me - at least compared to the pressure before I rebuilt the engine. Before the rebuild, I remember having less oil pressure. The needle was somewhere between half & 3/4 on the gage.

Now for those of you who've seen these 1958 gauges, you know they're not calibrated into micro units - a zero on one end, a dot in the middle & the 60 on the right. The engineers in 58 didn't believe much in fine tuning, I guess.

Anyhow, when the engine is running, my needle is well up in the high range (near or at 60 on the gauge).

Is this normal for a newly rebuilt engine or is something amiss? What can I check to verify everything is OK?

THX.

sounds good to me, especially if you got a high volume oil pump in it
w/ the fresh 283 in my 58, the gauge pegs at cold start, and stays there w/ rpms much above idle until well warmed up - never falls below about 45 driving, maybe 35/40 at slow idle when hot
give it a few hundred miles to break in - I'd be worried if a fresh 283 didn't get above 3/4 on that gauge when first run!!

Bill

Thanks bud. I needed a little reassurance that all was well. The gage doesn't actually peg but it's in the "darn near" range. I thought I might could have a blockage somewhere.

I was looking forward to driving her tomorrow. However, while I was crawling around in the engine box tweaking & tightenin', & lookin', & smellin' & fussin' about on things to make sure everything was A-OK, I accidentally punctured the frikin radiator with the heel of my boot! Glad I had all that Navy training or I might not have known what to say when it happened!

Oh well, it was the original rad & was patched in a hunnert or two places. I was going to replace it anyhow, but it sure woulda been nice to be able to drive the old girl for a day before I hadda do it! She's been a garage queen since December!

I guess that'll teach me not to do the victory dance so dang soon!

THX for the reassurance on the oil pressure.

BTW - what weight oil are you running that far north?

I use 10-30 year round, but I do have a convection type block heater in the water line that I plug in when it's freezing - mostly cuz it's nice to have the heater blowin hot as soon as the truck starts and I don't like shiverin for 10 min till the trucks warmed up! in somewhat worn 283's/327's I've usually used 10-40

Bill

I use a straight 30 down in these parts. Don't have to worry too much about how long it takes the booger to get heat into the cab but I know where you're coming from. I wintered over in Idaho Falls one winter!

I've tried not to venture that far from the equator ever again!

If your bearing clearances are right, the oil pressure should stabilize somewhere around 30 to 45 PSI at a hot idle. It's not uncommon for pressure to go above 60 on a cold start. As soon a the oil reaches operating temperature, the pressure will take a noticeable drop.

Of course, one of my roundtrack racing friends liked lots of oil pressure, so he installed a big-block oil pump on his 350, poured it full of 60 weight oil, and added several shims behind the pump relief spring. The engine would run for about 5 seconds, and stall. After about 10 tries, I told him to keep it running long enough for me to check the timing. He fired it up, and went to full throttle. It ran about 15 seconds, shuddered a lot, and blew the side out of the oil filter. It gave me a bath in warm racing oil, since I was leaning over the carburetor, trying to check the fuel and timing. His oil pump shims had completely blocked the relief valve, and the load on the pump drive was stalling the engine. It probably developed 500 pounds of oil pressure or more before the filter blew! There can be such a thing as too much oil pressure!
Jerry