The Stovebolt Site Forums The Shop Area Engine Shop Low to no oil pressure

I'm running a 350 in this '59. Nothing about the internals were offered up when I bought the truck. Its got a little cam though. So now its out of hibernation and driven...short 5 to 10 mile jaunts. OK so when first warmed up mechanical oil pressure gauge reading 50 to 60 psi. When stat temp reached (180) 30 psi. Now I've incorporated a dual fan set-up with thermo-switch @ 195 (fans) on. Working as designed. But here we go. At idle I can watch the needle literally drop to almost zero pressure. Yes, ZERO! Engine running no smoke, no wet pipes, no external leaks, no stumble, no unusual noises, ??????? Oil level dead nuts on!
Not sure what weight/viscosity is in the pan. But relatively clean and not burnt.

Are you sure of the accuracy of the gauge?

My gut guess is cam bearings.

Is the indicated temp of the coolant now significantly higher than before the eFan setup?

The 30 psi hot you were reading is typical. Something changed, and I'm having a hard time understanding why the eFans would affect that, unless the engine is now WAY hotter than before. Coolant temp after eFans?

Seems odd that just adding the eFans would cause a change in oil pressure, so may be coincidental to that change (cam, main or rod bearing clearance being suspect, but unrelated to the eFans).

Since the oil is unknown, suggest doing an oil change and see where you are after that.

Trying to say out of this but can't. Change oil to viscosity recommended for that year of 350. It's 10 lbs per 1000 RPM.
@500 RPM that is 5 lbs......together with old mechanical gauge tolerance and gas thinned old oil, could look like zero. Don't worry about idle. Set idle RPM to spec. If it's a zero when driving at 30-40 MPH or it gets real hot, report back. I'm sure it's OK.

High oil pressure at cold start up is NOT normal. Indicates blockage/flow problems or wrong oil, dirty oil, thick oil or all that. After start up refer to above.

Yes, could be faulty gauge for sure. Will change oil first, probably run straight 30W conventional...see how it reacts. BTW, the few times I drove it before the fan conversion it was acting the same way.

Really, not sure what era the SBC is out of. Should run some block numbers. Still wouldn't tell me whats inside though.

Thanks for the input as usual.

See My edits. New oil and filter good idea. 30 wt is good. Nothing wrong with the motor just the monitoring system. I don't know if Mystery type oil additives are good or not. If they are, throw some in if they actually clean passages/holes. Who knows?

It may be possible to find another pipe thread port on the motor suitable for a direct/no tubing gauge to use as a reference to the other gauge. That is what I would do and have done.

Apache, misunderstood... thought you were saying the oil pressure behavior changed from before eFans to after eFans. Bart summarized better than I.

Roger that...maybe I can adapt a tee in the gallery at the back of the motor where the oil pressure switch would normally go and put a gauge? I'll have to investigate further.

The factory original oil light switch turns on at 7 PSI, so there are lot of engines running around with almost no oil pressure at hot idle. Unless the light starts to flicker, most people don't realize just how low pressure can go and still keep the engine lubricated. What's the pressure at full temperature and 2K RPM? If it's at or above 30 PSI at cruise speed, you probably don't have much of a problem. Try running 15W-40 oil, or straight 30 weight HD oil. DO NOT run 30 weight non-detergent- - - -it's not rated for anything with an internal combustion engine any more- - - -including lawn mowers!
Jerry

Sounds good Jerry appreciate the support. BTW, which straight 30W HD oil would you opt for?

It's hard to beat Shell Rotella, or one of the other oils intended for farm tractors or over-the road Diesels. Lately, I've been running "Traveler" brand oil in 5-gallon pails from Tractor Supply in everything we own, from cars, to trucks, to lawn mowers and motorcycles. I'm using 15W-40, but they've also got it in heavy duty 30 weight.
Jerry

I'm familiar with Rotella...diesels only though...never considered it for gas applications. Jerry, in my travels HD oils were strictly used in diesels only due to high sulfur fuels, and combustion gases...would wipe bearings in gas motors.

So who's blending the "Traveler" brand? Of all the oils that are available what got you trying this brand. Thanks

George

The major consideration was $$$$imple- - - - - -buying it in pails instead of quart bottles was cheap! Any oil with the gear-shaped API symbol for a particular application means it passes some very strict standards, and I've never heard of Diesel-rated oils giving problems in gasoline engines, at least during the 50-something years I've been using them that way. Dad used to use RPM DELO (Diesel Engine Lubricating Oil) in flathead Ford racing engines back in the 1950's, and I did the same thing on dirt track Chevy 327's in the late 70's- - - -never had an oil-related bearing problem that I can remember!
Jerry

VR1 30 weight is ok. I've had good luck with it, and it is available almost anywhere.

Its hard to argue with real life results like that. So, whats your take on Zinc additives for early SBC motors. Fact or fiction or is somebody really getting rich? I ran Brad Penn racing oil for a brief time in another hotrod years ago. Those guys (Brad Penn) in NW PA swore up and down they had found a vein of oil that was rich is zinc straight out of the ground. I know why its "green" in color.

VR1....???????

For a break-in run on a new flat tappet cam, a ZDDP additive is probably a good idea. After that, I believe it's in the "nice but not necessary" category. I wonder if the Brad Penn folks were just repackaging Kendall GT-1 racing oil- - - - - -back in the late 1960's it had a noticeably green color. Good stuff- - - -just very hard to find and expensive when it was available!
Jerry

Thanks again

Jerry, yes from what I understand you hit the nail on the head. The D-A Lubricants company took over the old Kendall refinery in Bradford, PA, rebranded the products as Brad Penn, kept the green oil color, (and same formulation at least for a time, I believe) as part of their marketing. They claim the oil is still cut from stock out of the original Bradford oil field.

The products are marketed as "the Original Green Oil," sort of an under new management marketing approach. Fast forward, and Brad Penn oil is now Penngrade 1, semi-synthetic, still produced in the Bradford refinery, and still green. Oil that is labeled Brad Penn may still be around online, but their website seems to have converted now to just Penngrade 1 products. It still has higher zinc (although I doubt that's right out of the ground), and is available in straight 30 weight or multi-viscosity. Places like Summit carry the oil.

I've used both Brad Penn (including their 30 weight break-in oil) and Penngrade 1 oil with good results, FWIW.