[whippledcobra]

So I just had a motor built. On first start up it took longer than I liked to build oil pressure. Right when I was about to shut it down the gauge went up to about 70 psi. After about 20/30 minutes of idle time the pressure fell slowly to about 5psi. I had to pull the motor and take it back to the builder. I bought a new oil pump and he put it in, the old pump was on my last motor that blew up. The builder says the motor is ready. I really don’t want to put everything back together to have the same issue. Is there anything else I should have them look at before picking my motor up?

 

[cobraracer46]

Who’s decision was it to reuse the old oil pump? If your engine builder made the call to re use the old oil pump then that fuck up is on him.
At the very least, I would inspect the oil pan for bearing material or other metal fragments.

 

[eschaider]

There is nothing wrong with reusing an old oil pump unless something is wrong with it. Was something wrong with your old oil pump? Who assembled the engine, the builder or you?

On a new build it is always a good idea to prime the oil system prior to start up. There are a number of threads on the site about how to do this. Do a search and read them.

 

[cobraracer46]

There is nothing wrong with reusing an old oil pump unless something is wrong with it. Was something wrong with your old oil pump? Who assembled the engine, the builder or you?

Engine oil pumps will experience wear. For example, the gears themselves can wear and increase clearances, the pressure relief spring can wear from the millions of cycles it goes through and it can be very difficult to properly install a used set of oil pump gears:

“Front-mounted pumps, which are driven by the crankshaft, have machined features called sacrificial nodes or a ring. Those features are used to center the pump to the crankshaft at the engine assembly plant. Due to the design, these will become partially deformed by the crankshaft (hence the term sacrificial) during normal engine operation. So a used oil pump will have these centering features deformed, which will make centering the pumps to the crankshaft very difficult if not impossible.”

Additionally, Accufab shows that oil pump gears can experience wear and deposit metal throughout the engine

Accufab oil pump gear tech.

I would not risk engine damage by reusing an old engine oil pump.

 

[whippledcobra]

Who’s decision was it to reuse the old oil pump? If your engine builder made the call to re use the old oil pump then that fuck up is on him.
At the very least, I would inspect the oil pan for bearing material or other metal fragments.

I guess both of ours. It was the gt500 pump with boundary billet gears. It was on my previous motor for 4 years. That motor blew up on the dyno.

 

[whippledcobra]

There is nothing wrong with reusing an old oil pump unless something is wrong with it. Was something wrong with your old oil pump? Who assembled the engine, the builder or you?

On a new build it is always a good idea to prime the oil system prior to start up. There are a number of threads on the site about how to do this. Do a search and read them.

I don’t know if there was or not. Just figured with the motor losing pressure it’d be best to change it. When the builder swapped pumps he said the pressure relief valve was sticking a little on the old pump. The builder assembled the motor. I have read many threads on new motor builds and some people say prime and some say just fire it up. When I get the motor back in the car I’ll prime the oil system.

 

[eschaider]

I have built and rebuilt many different types of race engines for more than 50 years. I have never seen an oil pump that had worn out. I have seen oil.pumps that have been damaged because the pan was pumped dry or mechanically induced failures from foreign particulate matter being drawn through the pump but I have never seen one that wore out.

 

[whippledcobra]

I have built and rebuilt many different types of race engines for more than 50 years. I have never seen an oil pump that had worn out. I have seen oil.pumps that have been damaged because the pan was pumped dry or mechanically induced failures from foreign particulate matter being drawn through the pump but I have never seen one that wore out.

The old pump was on the previous motor that blew up on the dyno. I cleaned where the gears go but didn’t think to take the relief apart. Maybe something was in there? Is there any other reasons I was losing so much oil pressure?

 

[eschaider]

If no bearings were hurt, the only other place oil pressure could be bled off is a stuck pressure relief valve. Take it apart check for burrs and clean up any burred locations you find before reassembly.

 

[cobraracer46]

I have built and rebuilt many different types of race engines for more than 50 years. I have never seen an oil pump that had worn out. I have seen oil.pumps that have been damaged because the pan was pumped dry or mechanically induced failures from foreign particulate matter being drawn through the pump but I have never seen one that wore out.

I tend to follow the example of race team that will automatically replace or mileage out components once they hit a certain number of miles because the preventative maintenance aspect is huge.

It does not cost a lot to get a new oil pump and in my opinion, it’s not worth risking an engine failure by reusing a oil pump.

on a side note, considering just how much these mod motors cost to build in both money and down time I believe that serious consideration should be given to a dry sump oil system to Guarantee the ultimate in reliability.

 

[eschaider]

I tend to follow the example of race team that will automatically replace or mileage out components once they hit a certain number of miles because the preventative maintenance aspect is huge.

It does not cost a lot to get a new oil pump and in my opinion, it’s not worth risking an engine failure by reusing a oil pump.

on a side note, considering just how much these mod motors cost to build in both money and down time I believe that serious consideration should be given to a dry sump oil system to Guarantee the ultimate in reliability.

Everyone is entitled to their own opinion. When they are paying the bills, you can add to that, their own decisions and choices. A ready to use GT500 style pump approximates $500. If your opinion and your budget support that level of component maintenance and you want to do it, then by all means you should do it.

Over more than 50 years I have never found, absent damage from foreign particulate matter, an oil pump that had worn out. Worn out oil pumps are an oxymoron. They are the logical equivalent of saying,'faith unfaithfully kept him falsely true'. Think on that one for a bit. If it sounds convoluted and stupid put it up next to a worn out oil pump.

 

[whippledcobra]

Got my motor back for the second time and decided to check some things and found that the pickup was bottomed out in the pan. So the builder obviously never checked the pickup depth and this was the problem from the beginning, not the oil pump.

 

[01yellerCobra]

Glad you checked it. It would have sucked to get it all together and have the same issue.

 

[eschaider]

+1 on what Bob said.

The final fitment and assembly of otherwise perfectly good pieces can result in catastrophic engine failure if little things like this are modified or overlooked. If you were using OEM components i.e. pan pickup etc. the clearance should have been correct as delivered by Ford. That means someone had to alter the assembly or pieces. Might be interesting to do a little Sherlock Holmes detective work.

Depending on who you talk to you will get some variation in terms of proper pan to pick up clearance. If you follow the Moroso instructions they provide with many of their pans it will call for 0.250" to 0.500". This obviously works or we would hear a lot of noise from guys with blown up engines. I prefer a slightly different spec. I will shoot for 5/16" to ⅜" clearance. I am sensitive to potentially restricting the inlet to the pump by placing it too close to the floor of the pan.

At the same time I am also sensitive to too high a placement, which in effect reduces the oil pan volume the pump 'sees' in the pan. The first idea is relatively easy to visualize in our minds. The second takes a little more effort. We know better than putting the pickup 4" off the bottom of the pan because it will experience interruptions in the oil feed as the oil level drops below the pickup and the pump begins to pump air instead of oil.

While an extreme example, the same thing can happen with the pickup closer to the bottom but still too far off the bottom of the pan, especially if it is a small pan — read OEM. At idle and low engine operating speeds the engine uses a quart or so of oil just to wet the inside of the engine. Put another half quart into the various oil galleys and a 7 quart pan is now down to 5.5 quarts. After we pump the oil through the oil galleys to the bearing surfaces we are trying to lubricate, it has to get back down to the oil pan. Put a half quart in transit back to the pan and another half quart in crank and rod induced windage which creates a foamy unusable batch of aerated oil that has to loose all its air bubbles before it is worth pumping back into the oil galleys for lubrication purposes.

Let's say your sump is 8" x 8". A 1 Inch deep slice of that sump would be 64 cubic inches. A gallon has 231 cubic inches. The 1 inch tall section of your sump contains 1.1 quarts of oil. We are starting to get into oh-wow territory when it comes to useable oil volume in an oil pan.

Lets go back to the idle problem to close this out and recreate it at 6500 rpm. Your engine will be walking a fine line in terms of proper lubrication. Now raise the pickup too far off the bottom of the pan and you either draw in air or you are drawing in aerated oil which is almost as bad. There is not a lot of difference between ⅜" and ½" clearance off the bottom of the pan. When we are dealing with 6 or 7 quart pans this can sometimes make a difference. Don't throw caution to the wind. Double down on reliability whenever you have the chance. A ⅜" clearance will not throttle the pump or your parts wallet.

To check clearance, put a hamburger sized wad of clay or putty on the bottom of your pickup that has been oiled on both sides so it does not stick and is easy to get out later. Put the pan on cinch it down with the pan bolts. Loosen the bolts and take the pan off. Put your hamburger sized patty on the workbench and slice it across a diameter. You will be able to directly see and measure your pickup to pan clearance.

 

[whippledcobra]

Well after the 2nd time the builder checked the motor, put in a new oil pump and the pickup depth fixed, the motor is still losing oil pressure….

 

[eschaider]

These are the most common oil galley plugs that should be present but are sometimes removed during cleaning and then forgotten during assembly.

Check you main oil galley plugs to see if they are leaking. This is the main oil galley plug location on the front of the block;

This is the main oil galley location on the back of the block. It uses a different diameter plug than the front;

This is the driverside head front with the oil galley plugs identified;

These are the oil galley plugs on the back side of the passenger side head;

These are the oil restrictors that meter the oil to the cylinder head reservoir that lubricates the secondary drive chain;

If the galleys on the heads (front and back) are properly provisioned and plugged and the main oil galley in the block is properly plugged at both ends then the only other place a leak could occur is the oil pump pressure relief valve — assuming the pump back plate is properly installed.

Lots of checking work and sometimes in difficult places. Hope the pics help.

 

[P49Y-CY]

those pics are very helpful, thanks ed. i recently obtained a spare set of cylinder heads (and also a nemak block) from a lincoln aviator that i plan to send to a machine shop for cleaning someday, and i want to be sure to remove all of the oil gallery and cooling jacket plugs so as to make sure that it all gets cleaned out really well.

one question about the above pic, the one that says "terminator only" for passenger side rear hole #507 (plug W705310)... why would that plug be present in terminator but not the mach, maurader, and aviator 4 valve engines? i thought they all utilized the same head configuration.

edit: at first i thought it was not there, but i just checked again and my spare aviator head DOES have that plug there.

 

[eschaider]

The particular Ford Doc that the pic came out of Chris, was for 4V Terminators and 2V Proletariat engines, which Ford elected to identify as 2V NGV engines in the doc. Ford was attempting to prevent people with 2V work from accidentally referencing 4V pics in the docs. To discourage this they would periodically explicitly identify something as Terminator or 2V NGV.

The 4V heads within any particular engine family at a given point in time were identical. The desirable, last generation "DC" heads could turn up on Aviators but not a Terminator because of the Terminator's place in the 4V cylinder head production timeline. An earlier generation, say a DB head, would be used with multiple vehicle lines.

Later in the 4V engine's production life, Ford began to build the heads side specific by eliminating some of the pipe plug options that were used to make the head side specific. This provided distinct right and left the head casting without any provision for pipe plug additions that could not easily be swapped side for side.

 

[whippledcobra]

Called L&M and talked to mike and he said without hesitation that my problem was bearing clearance. When I get the motor pulled I’ll be sending it to L&M. Obviously shops in my area can’t build a modular motor.

 

[eschaider]

Well, that is good to have a definitive problem assessment. BTW what are the bearing clearances right now?