Oil Presure Problem
 

I have a oil presure problem and look for answers. Here is what I have. New engine never ran (454).

The first start. It started quickly after fixing the timing (had timing 180 out at first). When the engine started it then built oil pressure. You could here the lifters build and idle improve, but never indicated oil presure. I put a mechanical gage on and still no oil presure. I have pull the remote oil filter off and put just a oil filter on. When the oil filter was off I pumped the engine with a corded drill and oil shot out. I am stumped. I have flow and it appears good flow. Any suggestion are helpful. Thanks

Re: Oil Presure Problem
 

Are U sure the remote oil lines are correct? If you have them backwards and are using a good filter, it will block the flow off instead of letting it go through. Did you prime the engine with the drill before firing it up for the very first time?

John S. :D

Re: Oil Presure Problem
 

Yes I primed the engine before starting. I also always build with bearing guard. The engine has a remote oil filter locator, but I already took it off to see if that was the problem. I have flow to the remote oil filter. When I had the filter off I primed the engine with a corded drill shot oil all over the transume. I also am now just using a pad mounted filter.

I is strange that there appears to be good flow but no oil pressure.

Re: Oil Presure Problem
 

Where do you have the sending unit or mechanical gauge located to read the oil pressure?

Re: Oil Presure Problem
 

Directly above the oil filter where the stock sending unit would go. Is there another location where i could sense the oil presure? Thanks

Re: Oil Presure Problem
 

My senders are on the back, top of the block, by the distrib.

Re: Oil Presure Problem
 

My oil pressure sender unit is also located in the back of the block. I have my temp sender located where you have your pressure sender at. I can never get a correct reading with temp at that location.

Re: Oil Presure Problem
 

So if you take the sending unit out of the block and crank it over do you get oil from that port?

Re: Oil Presure Problem
 

I need to check and see

Re: Oil Presure Problem
 

Where are the oil ports by the distributor? I would like to try a different oil port for to see if there is a internal block problem or the opening wasn't drilled?

Re: Oil Presure Problem
 

I moved the mechanical pressure gage to the pickup on the back of block behind the distributor and still no oil presure. I have oil flowing, but no presure. What could be going on? Where could I be missing a restriction?

Re: Oil Presure Problem
 

It almost sounds like the bypass is stuck open in the oil pump. If you have flow and no pressure. When reading it on the side or back of the block that oil galley is directly from the oil pump. If you had the pickup welded on and the pickup is in oil and the pump was torqued onto the main cap you should have pressure. Sometimes you can use an air hose and blow air backwards into one of the oil galleys and hopefully you can move the bypass valve around enough to un lodge it. That sounds like the only thing it can be with out seeing it for myself. :(

John S.

Re: Oil Presure Problem
 

Where do you blow air? Directly in the oil pan?

Re: Oil Presure Problem
 

in the oil galley where you pulled the sender out.....id try several short blasts

Re: Oil Presure Problem
 

I will give it a try. What air pressure would you recommend?

Does the bypass allow the oil to flow through the cam and main bearings? I am getting oil flow at the filter and both oil ports

Re: Oil Presure Problem
 

I would try 80 psi at first, just be careful of blow back....( oil all over the place)

Ive never tried it but makes alot of sense and havnt known John to be wrong

Re: Oil Presure Problem
 

Is the bypass in the oil pump. I know there is a bypass in the pad were the oil filter is. Is there also one in the oil pump. This was my first (pair) of Big Block Chevys and I don't reminder the oil pump that well

Re: Oil Presure Problem
 

Yes, the bypass I am talking about is in the oil pump top cap. Remove the sending unit from the top hole in the back of the engine and put the air in there. You should use a rubber tipped air nozzle, push it in the hole and blast air a few times to make sure you get all the oil out of the oil galley. You should hear a hudge bubble in the oil in the pan. After that let the air flow a few times to hopefully unlodge the bypass. You kinda want the oil in the galley when you hit it hard with air because the hope is to use the oil flow backwards to help loosen the bypass valve.

Good luck, let us know how it goes. After you blow air, put the sending unit back in or the plug or the gauge and start the engine up. Keep an eye on the gauge.

John S. :D

Re: Oil Presure Problem
 

i have a sneaking suspicion that someone failed to put the oil galley plugs back in after the block was cleaned and it is just pumping the oil straight back into the front cover...

also... wern't there two types of distributors ... one that sealed the oil gallery internally and one that didn't ?

Re: Oil Presure Problem
 

I will try it tomorrow. I have been priming the engine to check for oil pressure. The st engine shows oil pressure this way, but the port doesn't. Why do you say to start the engine. Is it a valid way to check with a corded drill priming the pump and a mechanical gage.

Re: Oil Presure Problem
 

youll get pressure but not very much

Re: Oil Presure Problem
 

Why is that? I have a priming tool and hefty drill. Would it have enough presure to indicate on a mechanical gage. My starboard engine did, but I want to make sure that I am not chaing a ghost.

Also, I am afraid to start the engine without oil pressure. Thanks for the help

Re: Oil Presure Problem
 

OK, do not start the engine. Put a good mechanical gauge back on the engine and prime it with the drill again. Didnt know if liked taking the distributor in and out so many times. Keep in mind it may also be like the other person stated, oil galley plugs may have been left out. I think you would still have pressure at the main cap at the rear, but we will see.

John S.

Re: Oil Presure Problem
 

im starting a pool..... ive got 20 bucks that says its the galley plugs

Re: Oil Presure Problem
 

Well, lets think about this for a second or two. Even if the oil galley plugs are out, they are above the oil pump and rear main cap. Where are there plugs: The back of the block above the cam- oil would be leaking out into the bilge. Front of the block above the cam- The lifters aren't moving so the chance of oil even getting there are slim to none. If its a GenV,VI or VII and the lifter valley plugs were left out again the lifters are not moving hense no oil to the top of the engine.You might have a little from the mains feeding the cam bearings but very little with a drill. When that oil pump is spinning it should be moving oil to the mains and the oiling system. The engine usually has to be in motion for the lifters and valve train to get lubrication. The 2 oil galleys we are refuring to should have pressure even if the other galley plugs are out, the only differance would be is the rest of the engine above those plugs wouldn't recieve enough if any oil for lubrication.
We dont live in a perfect world and ANYTHING as we all know is possible! Especially trying to fix something over the phone or internet with out seeing it for yourself!

John S. :D

Re: Oil Presure Problem
 

I know remote diagnostic are near impossible. I appreciate everyone help. I have never had to fight a no oil pressure problem in any engine that I have built . I have had low oil pressure because of old mains, but this is the first no oil pressure. To further complicate that it have flow (and a lot at that) but still no pressure. I am going to try to see if the bypass is stuck using air pressure as you suggested.

Dinner then an short evening project. Thanks again to all for the help. I am trying all I can not to pull the engine. I will update.

Re: Oil Presure Problem
 

Remove spark plugs and have an assistant roll over the engine via the prop or prop nut jammed against another. Do this while priming with the drill. Use a 2K rpm drill. Look for oil off the rocker tips and keep an eye on the gauge. You should hear and feel the drill slow down when you get pressure.

Re: Oil Presure Problem
 

I was unable to unstick the bypass or it wasn't stuck. I am going to check for oil plugs. Are we talking about the plugs under the timing cover? Are there any others I should look at? Thanks

Re: Oil Presure Problem
 

I think the plugs they are refering to are under the intake manifold by the lifters. If these are removed you will have no pressure.