When I start my car up I have oil pressure. As it warms up the oil pressure drops to about 10psi or less. This is a new engine (roughly 3k miles) with many mods -- see pic. It is a melling HV oil pump. The gage is new and I still have to check the gage to see if its just the gage. When it is cold the oil pressure is about 50-60. Do you think the oil pump is already gone. I shot some nitrous through the motor (200hp) but the internals are pretty bulletproof. See sig

 

A friend of mines 4.3L S10 did this...same type pump to. At first we thought pump was shot but it was his bearings that where shot(clearance) on his, when cold it was normal (a lil low maybe), but as soon it warmed up it was darn near 0, we held it up temporarily by running straight synthetic 50wt oil (Valvoline) and Lucas Oil stabilizer. It been going for over a month like this, but he only drives 25ish miles a day though. Don't know if any of that helps though

 

A SBC will live happily ever after with about 10psi per 1000rpms.

If it makes you nervous, run some heavier oil. Straight 50 in a street car is a tad extreme though.

I see you mention that its a new guage. I assume that means aftermarket? If you're trying to use the stock guages, forget abot it, between the sender and the dash PCB the oil guages in these cars never work 100%

 

Just a few more questions:

What is "cold"? Ambient temperature?

What viscosity oil are you using?

What is the coolant temperature when the engine develops that "0" oil pressure and at what idle RPM?

 

ed is right about the factory gauges....

do yourself a favor, and get a known good mechanical gauge to check your oil pressure...

 

Sounds to me like you need a crank kit, like now, before it fills the motor up with metal shavings and/or ruins a rod, either of which will require a total tear-down and rebuild.

Oil pumps don't just "go bad" in that way. The only thing that will cause the symptoms you describe is an internal oil leak. If your engine is assembled correctly, about the only thing that can create such a leak, is bearing wear.

I also don't think the factory gauge stuff can or will fail in such a way as to produce what you describe.

"The simplest explanation that fits all the facts is usually the right one".
-Occam, ancient Greek philosopher, from the days when main bearings were made of molten Babbitt metal poured into saddles in the block

 

The problem is that I have like 15psi max. I havent run the car because of the winter but I have a semester break in 2 weeks where Im gonna try to start it and get it going. I have a fear that I will have to take the whole motor out. I have a lifetime labor warranty on the motor but I have to take the motor to the guy. I have always seen some oil leaking from the motor and assumed it was the valve covers. After adjusting the valve covers tons of times maybe Im wrong and its coming from somwhere else as someone suggested.

What will be the best steps to figuring out the problem before the engine pull. I am running 30-50 I believe (not synthetic... the builder said not to.)

cold is room temperature. Hot is about running temp 200 ish. I get about 0psi when it is warm at idle. Im not sure the temp... havent driven the car since september.

idle RPM of the car is ~1000

RB83L69 Wht do you mean by crank kit. New parts?? The entire engine only has 3k miles on it all new parts... That would be crazy if things are already going on it.

 

Pull it. It has something wrong and it should be returned as soon as possible so the rebuilder won't question it.

Sorry about your problem,
Charlie

 

Does your car die once it gets to 0 psi oil pressure?

 

Save yourself a lot of headaches and sleepless nights. Get a mechanical oil pressure gauge and connect it to the engin to test the REAL oil pressire. Chances are, the oil pressure gauge sending unit is FUBAR.

And DON'T use Lucas "oil satbilizer" on a low-mileage engine. I wouldn;t use it on even a high mileage engine, but that's just me:

http://www.oilanalysis.com/message_b...essageid=10861

 

Just because an engine is fairly new doesent mean its not damaged. The builder could have used the wrong brearings or someone could have broke it in wrong, ran it low on oil or what not, It happens. Use a mechanical guage and check for real pressure, like mentioned many times above the factory guage isnt an exact indicator of whats going on, I beleive RB put it in another post as "an option not an instrament".

 

Right.... "a trim package, not an instrument"....

But, the factory trim package is not usually sensitive to engine temp. It does other weird and wrong things, but not that one, usually. Most often, it fails by either reading high all the time or low all the time, or jumping around erratically. But nothing about it is subject to change with temperature.

It's always a good idea to "get a second opinion" when your gauges are telling you something that doesn't seem to make sense. But in this type of malfunction, I don't believe I'd suspect the gauge.

Crank kit = crank + set of main & rod bearings; you can buy them over the counter that way, in a box.

Just because it's "new" doesn't mean it's immune from failure.

Also, I'd recommend not putting the HV pump back in. This is a classic case of why they don't help a stock motor. There's nothing that can go wrong with an engine that a HV pump will cure, or help, or even slow down. Use a regular Melling M55, a Mr Gasket 26 regulator spring, a Melling 55S screen, and a Melling IS-55E oil pump drive shaft with a metal collar instead of a plastic one.

 

Whats wrong with Lucus? My friend uses it on his built up 350 and said he loves it.

 

Did the engine builder weld the pickup to the pump? possibly if the spring was left in while the pickup is being welded, it can toast the spring and you won't have much pressure. Check with a mechanical gauge.

 

The car has been sitting for a while and I cant get it started plus here in mass we got about 30" of snow. I am on semester break in a week and Im gonna try to get it going. I have a feeling I will have to pull the motor. At least I have a lifetime labor warrantee. I am assuming either way if I dont have oil pressure with the mechanical gage then I have to pull the motor??

Thanx for the help guys!

 

That'd be an affirmative. A new mechanical gauge isn't gonna die on ya or act up like an electric will, cause there's no power source, no sender, no ground, blah blah blah...it's just a freaking tube.

Always check the cheap before assuming the expensive.

 

It's a carrier oil with almost all polymer additives and no antiwear additives. All it will do is temporarily thicken the oil until it turns to soot, ash, sludge, and varnish.

 

just a question you said it was an aftermarket gauge that you havent checked yet right and this motor is fresh is the sender the proper ohms for the gauge?

 

What viscosity of oil are you running?

I would think with your setup the engine would have been built for high RPM and have additional bearing clearance, hence needing a heavier oil to maintain proper pressure at idle when warm. Try going to a heavier oil first.

Oh never mind, I din't see that you were running 30-50 and have no pressure, you have major trouble in the bottom end. If you pull the motor, check and see if the builder installed the galley plug the directs the oil through the filter. This is a common mistake some people do and will cause premature failure of bearings due to lack of filtering.

Good luck,
Charlie