Engine: Oil Pressure Readings

[Lou Van Anne]

When I start my R2 Hawk the oil pressure reads 40. When I start to drive it reads 60. After it warms up it reads 10 when idling in drive....how big a problem do I have?

[Mike Van Veghten]

None...!
Sounds like a fairly healthy engine.

You can raise the idle (and the rest) pressure a little by "blueprinting" the oil pump...but... Your numbers have been the same basic pressures in my 259 for over the last 90,000+ miles..!

Mike

[Commander Eddie]

I agree. My '55 President runs about those same numbers. My '61 Champ 259 was rebuilt some time back and does not drop that low at idle when hot and I don't know what modifications may have been made to the engine during the rebuild.

[TWChamp]

My 1950 Champion runs about the same, but doesn't go below about 20 at idle. After warm up and driving mine stays on 40 lbs. I use Mobile 10-30 oil. My temp gauge stays right at the low end of the flat circle range bar.

What weight oil are you using?

[studegary]

When I start my R2 Hawk the oil pressure reads 40. When I start to drive it reads 60. After it warms up it reads 10 when idling in drive....how big a problem do I have?

I do not believe that you have a "problem". Perhaps your oil pressure relief valve is overdue for servicing or the spring is weak. Other than that, we would need to know the viscosity (weight) of the engine oil and the temperature when "it warms up" before further comments.

[Lou Van Anne]

5W30 weight oil @ 180 degrees.

I do not believe that you have a "problem". Perhaps your oil pressure relief valve is overdue for servicing or the spring is weak. Other than that, we would need to know the viscosity (weight) of the engine oil and the temperature when "it warms up" before further comments.

[rockne10]

The "idiot lights" on vehicles so equipped don't come on until you've dropped to six or seven PSI at idle. I would say you are still in comfortable shape. Any Studebaker I've run with some wear on the engine, I've used Rotella 15W40 diesel oil. Could boost you a few PSI and give additional peace of mind. I've gone to 10W30 in fresh rebuilds.

[Tom Bredehoft]

Studebaker only considered the oil pressure in an engine at operating temperature, in drive (or road) gear at 40 mph. They liked the pressure then at 40#. Ignore pressure at Idle, there's no load, no need for pressure.

[studegary]

5W30 weight oil @ 180 degrees.

Why are you using 5W30? I know that is what is recommended for new cars, but not for 50 year old cars/technology.
I would use at least 10W30. Where you reside, straight 30 should be fine.
I know that they should all end up at 30 when up to temperature, but with all of the viscosity reducers in them for cold starts, that may not be the case.

[StudeRich]

Even though we all agree that probably no immediate harm should happen at 10 PSI idling in Drive, it IS a lot less than normal for a full flow V8 Engine.
Many of mine, at least a Dozen, have always idled at 30-40 PSI but of course I would never use less than SAE 10W-30 Oil and I still do not think going from 5 to 10 will bring it up enough though.

On this Car, a Known accurate or just a cross check Gauge may be in order though.

[jackb]

double down on a good non-China gauge to see what you really have there. A low idle pressure may suggest cam bearing clearance issues, or not. I'm with Rich - 20+psi @ idle is what has always been earmarked for any engine I wanted any real duty from. But that's from a daily/quasi-daily driver. Seasonal use allows for your ranges.

[Lou Van Anne]

Thanks everyone.

[64Avanti]

I have always seen 30-40 psi at idle on a Stude V8 unless it was worn-out. I remember being shocked that an Olds 425 idled at about 10 psi.