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.

[skidmarks]

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

[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.

[34PKUP]

Originally Posted by 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?

Originally Posted by Kube

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.

The 95% filter system is not a bypass system, it does not use a restrictor fitting.

[V8 Bob]

Originally Posted by 51 MERC-CT

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

The adapter is well id'd for oil flow. The 30 minute break-in was pretty normal with pressure starting around 40 and ending with about 10 psi hot idle. It was during the second run that something happened when the pressure went from 10 to a solid 45.

[51 MERC-CT]

Originally Posted by V8 Bob

The adapter is well id'd for oil flow. The 30 minute break-in was pretty normal with pressure starting around 40 and ending with about 10 psi hot idle. It was during the second run that something happened when the pressure went from 10 to a solid 45.

At least it's one thing to cross off the list.
The next thing I would check (before any tear down) is the oil pressure/sender gauge operation.

[V8 Bob]

Originally Posted by 51 MERC-CT

At least it's one thing to cross off the list.
The next thing I would check (before any tear down) is the oil pressure/sender gauge operation.

The gauge is a new mechanical 100 psi VDO and checks OK. It is plumbed into one of two filter mount output ports.

[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.

[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.

[Bored&Stroked]

Kind of a strange situation - some things to ponder - or be concerned about:

1) Initial low oil pressure: There are a few things that can cause this:

a) Blowing rod journal clean-out plugs out of the Merc Crank. I've done this and ended up with exactly the same original situation as you noted on the first run.

b) Slippage of the oil pump drive gear on the back of the cam. There is a very small flat spot on the cam that is supposed to prevent the drive gear from turning - have had issues with that before with heavy oil. I now put a small 'tack weld' on any engine with large bearing clearances that will be running heavy weight oil.

c) Pressure Relief Valve - 49-53 Oil Pump: I've seen a case where poor machining caused this valve to function incorrectly - releasing too much pressure too soon.

d) Oil Pump Casting to Block Fitment: I've seen an oil pump where the bottom flange of the oil pump didn't completely cover up the hole in the block where it mounts - bleeding off oil pressure.

e) Pressure Relief Valve in Block - Pre-49 Blocks: I've seen cases where this was left out or was missing the spring, or the wrong spring . . .

f) Oil Galley Plugs Missing: There are two - one in the front of the block (behind cam gear) and one in the rear.

g) Cam Journals Undersized: I've seen cams with .010 undersized journals - running in STD sized bearings.

h) Bad Oil Pump

2) Puffs of smoke out the exhaust - after a warm-up. Regardless of the oil pressure situation, what was the cause of this situation? Can you elaborate a bit more on this situation? Was it at idle? Did it appear to be oil smoke? Did you see it on the second run?

a) This situation concerns me - in that I don't really know what could have changed and if this has anything to do with your oil pressure. It maybe completely unrelated.

b) If you have or can borrow the tools, would want to do a leak-down test to see how all the cylinders look.

3) Higher Oil Pressure the Second Run: Seems awfully strange that the oil pressure came up and stayed at a constant 45 lbs? I've never seen this situation - the pressure always moves with the throttle. When I'm building an earlier block (front pressure bypass) - and a late 49-53 pump (which is all I use), I stretch the front spring to ensure that the pressure relief spring on the pump handled the pressure control. I typically see 30 or so lbs of oil pressure at idle with a good later pump - even when hot - with 60+ lbs when revved up.

Things to ponder on this:

a) If the filter media was clogged AND you were taking the pressure reading on the out-bound side of the filter adapter, then the pressure would not be high due to the clog.

b) If your filter has a pressure relief valve, then it should just bypass.

c) I've never seen a 'stuck' pressure relief valve in a late 49-53 pump . . . maybe others have. BUT - if this was the situation, then I'd expect to see high pressure numbers at higher RPMs . . . with the pressure coming down at idle.

4) Cut Your Filter Apart - Check Bearings: If it was mine, I'd cut the oil filter apart and see if I see anything ugly in the filter element. I'd surely be looking for any sign of bearing flaking. Since you're pulling the pan - at least you can check the bearings (I would).


Final Thoughts: So - this is a strange caper in general . . . lots to check-out and ponder. Hopefully you can do some expert sleuthing and figure it out. Best of luck and keep the communication coming!

B&S

[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.

[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

[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.

[V8 Bob]

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Bored&stroked,
I'll try to address your questions.


1) Initial low psi:
a) The clean-outs were tapped for pipe plugs I installed and staked.
b) Possible, but with 10W30 and very high final pressure, probably not.
c) Possible.
d) No issue.
e) Visual inspection looked OK.
f) I carefully assembled this engine-no missing galley plugs.

g) This was checked and is OK.
h) Hopefully this is the problem.



2) Puffs of smoke.
a) Light puffs were noticed during the first few minutes of break-in then disappeared. During the second run a day later the engine ran clean until the psi became high. Definitely oil smoke.
b) I'll look into doing a leak-down.



3) Higher psi.
The pressure is taken from the output of the filter, hard to see in the pics above, but opposite the feed hose to the block.
The filter is a common Ford (Motorcraft) FL-1. I agree the filter would just bypass if plugged and not affect psi.


4) When I pull the pan I'll check the bottom end. The filter will also be examined.

[Ol' Ron]

I've never used an aftermarket oil pump, since I had to replace several Mellings, back in the 90's. Hope they have improved their quality control issues in China. I use old ford pumps ever since. However 10 at odle and 40 running in cruse is more than enough.

[tubman]

Originally Posted by Ol' Ron

I've never used an aftermarket oil pump, since I had to replace several Mellings, back in the 90's. Hope they have improved their quality control issues in China. I use old ford pumps ever since. However 10 at odle and 40 running in cruse is more than enough.

Everything you say is true, but I'd be very concerned with oil pressure numbers like that on a fresh build, especially with a late pump.

[GB SISSON]

While it isn't a ford engine, I installed a used 220 cu in cummins inline six in my 59 f350 a few years back. It never had the oil pressure it should. Rebuild parts were very $, so I found another good engine and installed it. Just had to take the old one apart to check. Here's what I found. In the oil pressure relief valve at the front of the block there was a chunk of foreign matter shaped like a spear point jammed under the plunger. I puled the spring and got it out in one piece. I pinched the chunk and it crumbled, that's why I think it was sand, maybe carbon. Oil pressure went straight to factory new specs. Perhaps a chunk of hard crud from the crank or somewhere else was lodged in your pump. My .02 on your situation.

[V8 Bob]

The lower than expected pressure is one thing, but the main issue now is how or why the pressure went from 10 psi at warm idle to a solid 45.

[Ross F-1]

Like GB says, I'd assume there was a chunk of something on the relief valve seat, that eventually got blown thru.

[V8 Bob]

Originally Posted by Ross F-1

Like GB says, I'd assume there was a chunk of something on the relief valve seat, that eventually got blown thru.

Ross, hope you're right, just hard to believe a stock pump could produce 45 PSI at idle with 180 degree water temps and 10W30 oil.

[tubman]

If it's a good 8BA pump on a fresh engine, it's not surprising at all. Both of my last builds did.

[Ol' Ron]

Is it possible that the lines from your remote oil filter are crossed. I had that happen to me once. depending on the type of filter your running you could have the hi pressure.

[Ol' Ron]

Is it possible that the lines from your remote oil filter are crossed. I had that happen to me once. depending on the type of filter your running you could have the hi pressure.