Oil Pressure Question

[Jason Scott]

I recently had my 53 straight 8 rebuilt and still rely on the stock oil pressure gauge. Valvolene 10-30W oil used. I was curious if anyone knows what is "normal" for this gauge. On cold start up the gauge goes up above the N mark to about 3/4 but never all the way to "high" H. After warm up, upon acceleration and speeds above 30mph the gauge reads at N "normal" or a little above. But at a stop the gauge drops to the 1st hash mark and when slowly starting out in 1st gear (manual) I've noticed that the gauge drops practically almost to low L and then gradually comes up with increase in RPM's, to "normal". When driving at highway speed 70-75mph, the gauge is always at the 3/4 mark above N but never at H. Does this sound like proper operation?? I don't really have anything to compare it to. The car does not run at a fast idle and really seems to run great. I suppose if I increased the idle setting, a bit the gauge would run "higher". I'm probably paranoid! Any thoughts?? Jason

['60 flattop]

Hi Jason!

The way your oil pressure gauge functions seems pretty much normal to me. When the oil is cold, as when you start your engine, the oil pressure is high, but as the oil pump has a spring loaded valve, it won't go sky high.
When the engine (and the oil) warms up, the oil pressure will get lower, and if everything is ok it will be reading "normal".
At idle the oil pressure may be quite low, especially if you use a low quality or synthetic oil.
All this is more or less exactly as you describe your operation of your gauge, and you shouldn't worry if it never goes up to the H-mark, but it maybe would if you tried to start it on a very cold winter morning when the oil is more like grease...
I wouldn't be too concerned about the idle speed either, as there is very little stress on the engine when it idles, besides, a fast-idling engine doesn't sound very cool , worse is to floor it at 4 mph in third...
If you really want to be sure, maybe you could have a shop test your oil pressure, so that you get real psi readings.

[Jason Scott]

Thanks for the help, 60 flatop from Finland. Jason

[Jyrki]

So, there are at least 3 Finns on this forum. Considering there are only 5.2 million of us, we must be "outnumbering" all other nationalities here!