Fresh 8BA oil pressure problem

[V8 Bob]

I tried to find a thread or info similar to my problem with no success, so here it is....
I just ran a fresh 276" on my engine stand Thursday. Some details are Merc 30/30 crank, L-100 cam, Egge pistons, Chevy s/s 1.5 valves, Isky lifters, and 95% full flow oil system. The standard oil pump was purchased new but don't remember the source.



I pressure pre-oiled using a garden sprayer with 4 quarts of 10W30 Valvoline VR-1 and could develop 15 psi with very slow leak down, thinking there are no serious leaks and that the oil system is A OK.



Initial start-up resulted in about 40 psi oil pressure, which seemed low but adequate. Temps came up to the 180 T-stat ratings, the engine ran strong and break-in lasted about 30 minutes. Oil pressure, however, dropped to 10 at 900-1000 rpm, near 0 at very low rpm.


After a cold head bolt re-torque Friday, I restarted with the same 40-ish initial oil pressure and let it warm up while I re-set timing and adjusted the temporary single 94 carb (on a stock intake). All seemed well until I noticed puffs of smoke coming out the exhausts. A quick look at the gauges showed a solid 45 psi oil pressure a idle, with no movement when changing the rpm. After about a minute I shut it down with the same 45 psi reading.


I will pull the pan and remove the pump when time allows, but would like your input on what the heck happened or what the problem may be. Thanks. Happy New Year!

Bob

[JSeery]

What kind of clearances are you running on the rod bearings, main bearings and cam bearings? Are you running any type of filter?

[Kube]

Be certain there is a restrictive fitting on the pressure side of the oil filter. Fitting should reduce to .055" - .063".
Check that first as it must be in place.
We can work from there.

Stock 40# pump?

[JSeery]

Ok, just noticed, he is running the "95%" filter modification. I would start with that and be sure everything is working properly and that the filter is not clogged with some rebuild debris.

[V8 Bob]

Everything is new-filter, hoses, filter adapter. Bearing clearances are typical .0015"-.002". The FL-1 filter is mounted on a modified 8BA mount on the LH head. Hoses are very short down to the back of the block, and pressure is taken at the remote filter adapter output.
I tried to post some pictures without success but will keep trying if it will help.

[Kube]

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Originally Posted by V8 Bob

Everything is new-filter, hoses, filter adapter. Bearing clearances are typical .0015"-.002". The FL-1 filter is mounted on a modified 8BA mount on the LH head. Hoses are very short down to the back of the block, and pressure is taken at the remote filter adapter output.
I tried to post some pictures without success but will keep trying if it will help.

Bob, What will actually help is if you answer all of the questions posed to you.
Is there a restrictive fitting in the high pressure side of the oil filter?
We really don't need pictures and don't care about the length of the lines.
What oil pump is in this engine?
If it's a stock pump, the 40# cold going to 10# warm is what you should expect.

[V8 Bob]

Kube, as stated earlier, the pump is standard (stock), and the block is modified for the "95%" full filtration-oil comes out the normal port, goes through a regular (Motorcraft FL-1 for now) filter and re-enters in a new drilled port towards the center, with a grub screw blocking in between. The filter fittings are steel #8 Aeroquip or brass and are not restrictive.

[51 MERC-CT]

Check to see if the input and exit points are correct on the filter holder/adapter.

[skidmarks]

Or disconnect the oil filter and put the gauge direct into the block

[tubman]

It sounds to me like the bypass in the oil filter was stuck open during the first run. With all of that hot oil coursing through it, the bypass was subsequently able to close, allowing the oil pressure to return to normal. It's important ton know what oil pump you had installed. The 10 hot 40 cold numbers "Kube" mentions might be OK with an older pump, they are woefully inadequate with a good late model (8BA type) pump. My last two builds, both 8BA's, had 45 lbs cold at idle and 25 lbs hot.

I also had a thread here last year about the second engine I did. I had installed a NEW Speedway oil pump and was dissatisfied with the pressure it provided. I replaced it with a used good known genuine Ford pump (checked out by "FlatJack9"; thanks Jack) which brought the oil pressure back where I had expected it to be. In the case of a flathead Ford, at least, the chice of which oil pump to use seems quite important.

[GOSFAST]

You need to make certain you have the "grub" screw in the oil passageway to direct the oil through the filter and then back to the system, it sounds like you may not have that screw in place? This specific issue has been mentioned up here few times in the past!

I know there are a few up here that have had certain issues with the Melling pumps but we've both used and sold hundreds of them through the years and haven't had a single "bad" one ever!

Is it possible you can get a close-up shot of the back of the block where you ran the hoses for the filter? The shot below is how we set up all our Flathead builds for the remote filter setup. The "screw" is located between the 2 fittings on the right and is in-line (straight inside) with the horizontal one on far the left. We use a 1/2"-13 allen-head set screw.

Thanks, Gary in N.Y.

P.S. Wishing all here a very "Happy New Year", and stay healthy!

[51 MERC-CT]

Originally Posted by GOSFAST

You need to make certain you have the "grub" screw in the oil passageway to direct the oil through the filter and then back to the system, it sounds like you may not have that screw in place? This specific issue has been mentioned up here few times in the past!

I know there are a few up here that have had certain issues with the Melling pumps but we've both used and sold hundreds of them through the years and haven't had a single "bad" one ever!

Is it possible you can get a close-up shot of the back of the block where you ran the hoses for the filter? The shot below is how we set up all our Flathead builds for the remote filter setup. The "screw" is located between the 2 fittings on the right and is in-line (straight inside) with the horizontal one on far the left. We use a 1/2"-13 allen-head set screw.

Thanks, Gary in N.Y.

P.S. Wishing all here a very "Happy New Year", and stay healthy!

Agree that the 'grub' screw should be in place for the filter to do it's job.
But (just a thought) if left out, wouldn't the oil flow just pass the filter and operate normally without any loss of pressure?

[V8 Bob]

Here are finally two pictures of my test setup. I apologize if the pics may be too large, but I'm having trouble posting pics on the forum.



Tubman, I agree the initial run-in pressures were too low for a new pump. I thought they should have been about 5 or more psi throughout.



Gary, the grub screw is in place as I performed the block modifications.

[Ggmac]

Do you use silicone sealant or Teflon tape ? Usually we all do , but too much or some misapplied , could cause blockage or springs to stick .

[V8 Bob]

Originally Posted by Ggmac

Do you use silicone sealant or Teflon tape ? Usually we all do , but too much or some misapplied , could cause blockage or springs to stick .

No silicone, and never Teflon tape. I do use PTFE (Teflon) pipe sealant on all pipe thread.

[Ggmac]

Originally Posted by V8 Bob

No silicone, and never Teflon tape. I do use PTFE (Teflon) pipe sealant on all pipe thread.

Excellent , I could never understand why anyone would use pipe tape on automotive . You have no idea how many fuel pumps I've seen with tape in the flapper .
Teflon has no sealant ,it's just slippery , that's my usual talk I have had with customers .
I must admit to using silicone sealant , sparingly !
I hope you get it worked out , I'm out of ideas , but I would run another gauge before the filter and one after just to compare pressure drop .
Good luck , Gary

[tubman]

I think the key fact here is that the oil pressure increased by a bunch on the second start. 10 lbs to 45 lbs is significant. It usually goes the other way if something is really wrong. My money is still in he relief valve in the filter. You're not using Fram filters, are you?

[40cpe]

I would tend to believe that the initial low oil pressure was related to the oil pump relief valve not seating. It sounds like the puff of smoke at the exhaust is what made you look at the gauge again to see the higher oil pressure. At this point I would be more concerned about the puff of smoke, was it white or oil blue? I would run it some more to get some stability and see if the smoke goes away or gets worse. Watch the coolant.

[V8 Bob]

Originally Posted by 40cpe

I would tend to believe that the initial low oil pressure was related to the oil pump relief valve not seating. It sounds like the puff of smoke at the exhaust is what made you look at the gauge again to see the higher oil pressure. At this point I would be more concerned about the puff of smoke, was it white or oil blue? I would run it some more to get some stability and see if the smoke goes away or gets worse. Watch the coolant.

I felt the same about the initial low pressure resulting from a possible faulty relief.

Smoke was lt. blue, just like during the initial run-in. My thought was too much oil on the fresh cylinders and new rings that may not be fully seated.

Oil is clean, and no water out the heads with the plugs removed.

A little nervous about any more running without a better understanding of what's going on. I ran it for about a minute after I noticed the 45 psi reading, trying to clean out the cylinders, without success.

[Bored&Stroked]

Originally Posted by V8 Bob

Smoke was lt. blue, just like during the initial run-in. My thought was too much oil on the fresh cylinders and new rings that may not be fully seated.

This sounds like a normal situation - as the rings are not yet seated into the bores. Keep in mind that rings don't seat on a run-in stand, or by running the engine without load.

Once you get the oil-pressure situation figured out, try to get the engine in a car and do some heavy initial break-in runs - this load is what seats the rings.

Don't make the common mistake of running the engine on a stand or not under load (cause it sounds so good ) . . . you risk glazing the cylinder walls and the rings may never seat.

Once you know you have good/correct oil pressure, have re-torqued the heads, have no gasket leak issues and have set your timing -- get the car on the road and break it is correctly.