Another low oil pressure thread

[Bolted to Floor]

Close to 500 miles on the motor now. With the first oil pump in this motor, it was close to 50 cold and hovered just below the 12.5 mark at 900 RPM. Gauge is marked 0/25/50/75/100 with 1/8 markings. I didn’t like it. Read through here here and learned about the Melling M57B and bought one from POPS. Now, cold oil pressure is closer to 70. Hot oil pressure has not changed. Hot oil pressure does climb with RPM.

Machine shop had mains at .002”. Rods are at .0025”. Rocker arms are resized with bronze bushings from Rocker Arms Unlimited with matching shafts. Oil to the heads is restricted, .070, I think. Thrust and rod side clearance are within spec. Block got typical oil mods and screw in gallery plugs.

Since the front seal is leaking, figured I would pull the distributor and spin the oil pump to see if anything look out of place. I can see the screw in plug behind the distributor. Spinning the oil pump, I get a stream of oil out of that plug!! Is that supposed to be that way?? It looks like it’s squirting a stream at the distributor gear.

Here is a video.
https://youtu.be/I2FNUaNudns


Thanks for looking.

Edit to add engine oil - VR1 10W-30

[jayb]

It is not supposed to be that way.  Hole in the plug maybe?  It doesn't have one of those little dribble valves in the plug, does it? 

[1967FEGT]

I have seen a couple of engines with the galley plug drilled to lubricate the distributor drive gears..  It's not necessary and would bleed off oil pressure.
I have all the mods done to my engine as well with the rocker shaft supply at .070.
I have a POP blueprinted high volume pump. I have 82psi cold @ 1500.  Hot is 21 PSI idle at 900 and 60 psi at 3000 rpm.
I run two quarts of 20-50 with 4.5 quarts of 10-30 VR-1

[blykins]

That's a Chevy trick.  They drill the front galley plugs to pee on the timing set and thrust button.  Not needed on an FE. 

[blykins]

BTW, you should see oil down by the distributor shaft hole and that's normal.  There's a feed from behind the front cam bearing that oils the distributor.  However, that stream of oil shooting out should not be there.

[My427stang]

Agree with all, and with the clearances you have, you should have good oil pressure, assuming cam bearing clearance is good. That front plug can be done in the car, although you may swear about it and will need to be careful not to drop it inside.

However, that M57B won't help idle oil pressure either, as I understand, it's basically a standard pump with a HV spring (or close to it).  The bigger gears of the HV pump typically give better idle oil pressure and the spring determines the peak, so it did exactly what is expected.

Last thing I would bring up is the oil mods, in some cases, you can break through if you open up the primary galley out of the pump into the block, it'd likely be worse that you are seeing, but I have stopped doing it. I'd start with that dribble valve and then see where you are

[Bolted to Floor]

Thanks guys. I will have that plug pulled and replaced this weekend and report back.

[Falcon67]

My 351Cs run an Melling HV pump and clearances run in the 2.00+ range mains and rods.  Typical pressure is around 70 cold with 10w-30 and in the 30 range hot.  That is measured at the front above the oil filter, so close to pump output.  IMHO that pin hole oil squirt isn't the issue.  You may have a gauge problem.  I find it hard to think about how you'd get from 70 PSI cold to 12.5, if I'm reading the post correctly.  And not having any change with RPM.  On a super hot day here I can be 30 or below hot after a couple of runs but it's go right to 55~60 at 2000 RPM. 

[Bolted to Floor]

I'm running VR1 10W-30 oil, edit above top add.


I called the machine shop on Friday to ask about the hole in the plug. He tells me this was a practice he started in the last year or two from a couple of FE’s with noisy lifters.

The theory was air trapped at the end of the lifter bores. The cure was was grinding a shallow path in each lifter bore connecting the galleries. Then he drilled a the hole (.041") in the plug for the drivers side and the cam retainer bolt on the passenger side. That solved his noisy lifter problem.

After taking some time to think about it, if air is trapped....its at the end lifter on each gallery. This could help the front, but nothing gets done for the back.

For such a small hole, it sure shoots a stream of oil.

As a precaution, I have another gauge coming to verify the one I have is accurate.

With what Chris is saying, if one pin hole isn't the issue, maybe 2 could be??? I hate to pull this thing back out to dissect it.

Using a battery drill and a gauge, I will try to see if there is a difference on the pressure from having the holes to blocking them.

With the two streams of oil shooting forward, this could be the reason my front seal started leaking too.

Thanks for the feedback. I will come back with more info when I have it.

[blykins]

I'm running VR1 10W-30 oil, edit above top add.


I called the machine shop on Friday to ask about the hole in the plug. He tells me this was a practice he started in the last year or two from a couple of FE’s with noisy lifters.

The theory was air trapped at the end of the lifter bores. The cure was was grinding a shallow path in each lifter bore connecting the galleries. Then he drilled a the hole (.041") in the plug for the drivers side and the cam retainer bolt on the passenger side. That solved his noisy lifter problem.

After taking some time to think about it, if air is trapped....its at the end lifter on each gallery. This could help the front, but nothing gets done for the back.

For such a small hole, it sure shoots a stream of oil.

As a precaution, I have another gauge coming to verify the one I have is accurate.

With what Chris is saying, if one pin hole isn't the issue, maybe 2 could be??? I hate to pull this thing back out to dissect it.

Using a battery drill and a gauge, I will try to see if there is a difference on the pressure from having the holes to blocking them.

With the two streams of oil shooting forward, this could be the reason my front seal started leaking too.

Thanks for the feedback. I will come back with more info when I have it.

He had some bad lifters.  What he did was completely unnecessary and is certainly bleeding off oil pressure.  I have never cut any grooves in any lifter bores and have never drilled the front plug. 

[WConley]

I'm running VR1 10W-30 oil, edit above top add.


I called the machine shop on Friday to ask about the hole in the plug. He tells me this was a practice he started in the last year or two from a couple of FE’s with noisy lifters.

The theory was air trapped at the end of the lifter bores. The cure was was grinding a shallow path in each lifter bore connecting the galleries. Then he drilled a the hole (.041") in the plug for the drivers side and the cam retainer bolt on the passenger side. That solved his noisy lifter problem.

After taking some time to think about it, if air is trapped....its at the end lifter on each gallery. This could help the front, but nothing gets done for the back.

For such a small hole, it sure shoots a stream of oil.

As a precaution, I have another gauge coming to verify the one I have is accurate.

With what Chris is saying, if one pin hole isn't the issue, maybe 2 could be??? I hate to pull this thing back out to dissect it.

Using a battery drill and a gauge, I will try to see if there is a difference on the pressure from having the holes to blocking them.

With the two streams of oil shooting forward, this could be the reason my front seal started leaking too.

Thanks for the feedback. I will come back with more info when I have it.

He had some bad lifters.  What he did was completely unnecessary and is certainly bleeding off oil pressure.  I have never cut any grooves in any lifter bores and have never drilled the front plug.

    Grinding slots in the lifter bores is a great way to bleed oil pressure!  Look for big streams shooting up into the lifter valley when you're spinning it with the drill.  Some people...  If it was necessary Ford would have done it in the design.

[chris401]

Original press in oil galley plugs had a bleeder plug behind the timing chain. May not have been all years but it was done at Ford for a while. I drilled one in an oil modification I did. I do not recall any pressure difference at the gauge when I changed it. I reinstalled it with the following cam swap. May or may not make a difference but at $75 timing chain I want to get as many miles as possible.

EDIT: This was in a 66 block. I have seen it in later untouched engines but not in one that was rebuilt at some point. Those had standard plugs throughout. Seems the stock bleeder plug was also shown in either Steve Christ book or some FPP documents I downloaded. Factory placement is behind the chain, not the distributor gear.

[wayne]

Time to find a new shop thats a old bbc trick i would run a hv oil pump now you can bleed a lot from the lifter bores.A shop should ask be fore they start grinding on your block and let you say ok or not.

[Rory428]

Agree with Chris, I have see plenty of early FEs with a "piddle valve" oil gallery plug in the front. My understanding was that it was for helping to cure noisy hydraulic lifters due trapped air. That said, I have had plenty of FEs with hydraulic lifters and solid oil plugs, and I can`t say I ever noticed any noise like that. Even still, that seems like quite a differance in hot and cold oil pressure to me. I have had old FEs with lots of miles that had hardly any oil pressure at idle, that ran like that for years, but on a fresh engine, 12psi at idle is lower than I would be happy with, at least assuming those are the actual bearing clearances. It may well run for years like that , but I would consider trying another oil pressure gauge, just to be sure.

[rockhouse66]

I can't imagine any lifter/bore fit that would hold air pressure of 50 PSI!  That's the only way you could have trapped air.

[My427stang]

I can't imagine any lifter/bore fit that would hold air pressure of 50 PSI!  That's the only way you could have trapped air.

The end of the galley behind the distributor has no escape.  So, in theory, as the lifter bank pressurized, air could get trapped in that small end galley.  However, you are 100% correct that the air would stop there, if it existed at all, as the bore itself couldn't hold air and the lifter will get all the oil it wants.

I missed the grooving of the lifter bores, assuming all other clearances are good, especially mains and cam bearings, that is likely the issue.  That's a lot of oil to dump

[blykins]

In addition, that's another reason I prime the pump on the stand with no intake on.  You can hear the air burping after a few rotations of the primer.   I prime without rockers/pushrods first, then install the rockers and pushrods, double check my pushrod length/preload, and then pull the rockers/pushrods off to inspect the lifters.  There was one case where I did this and found a lifter with the plunger not coming back up to the top.  It saved me. 

[WerbyFord]

Just refreshing a 390 stocker these days.
x2 what Brent said about spinning up oil pressure with intake off.
Just watch out for the rocker idle holes - plug em tite or you'll have an Old Faithful mess of oil all over the shop (twice).

So, atandard M57 pump, used but good.
Clearances 2.5 to 3.0 on mains/rods.
60psi on the drill motor, all lifters in, rocker holes plugged.

Then I pulled 1E lifter in the front.
Still read about 58psi, almost no loss from having that lifter totally OUT.

Put it back in & pulled 8E lifter in the back.
Only 35psi.
Lost almost HALF the oil pressure due to a missing lifter in the BACK, but almost none if in the FRONT.
Makes sense as the lifter galleys are fed from near the back.

As an aside, I also set up a dial indicator to measure head gasket compression.
Thickness of the cylinder "ring" was .054 for the new gasket, thickness of the cardboard was about .050".
As I torqued the head, the dial gage dropped .015" so that's the gasket compression.
Surprised it was that much!

[Falcon67]

With the others - grooving the lifter bores is not a good solution and could be a problem source if your replacement gauge shows the same issue. 

I had an issue with very little oil coning up top on this 393C using Howards solid rollers.  An unusual situation on a 351C.  Howards said it happens sometimes if your bores are close to spec and in good shape since their lifters hold a tighter diameter tolerance than most lifters.  The recommended "fix" was a small nick between the lifter band and the oil hole in the lifter.  I "nicked" 16 lifters with a thin die grinder wheel.  Just a little more than a scratch, each maybe .125 long if that.  Just enough to catch your fingernail type cut.  After doing that and running the pump with a drill, I get a liquid ton of oil up top.  I mean a LOT.  So much so that I put some roll pin "restrictors" in #5 push rods to keep so much oil away from the vacuum pump pickup point.  If this 393C wasn't a short duration drag motor with 8 quarts in the sump, I'd have to either replace the lifters or go to restrictor pushrods to control the flood of oil into the covers. 

All this to say that it doesn't take very much to get into bleeding oil out of the lifter galleries to places you might not want.  Grooving the bores would really seem to me to be a way to lose pressure and volume.  If it was just the .041 hole, no so much - BUT...after thinking about it, that's about the size of the plug used to restrict oil going to the left side lifter gallery in a 351C running solid lifters. 

[wayne]

I think its got two .041 holes one in the plug and one in the cam retainer bolt plus the lifter bores.

[DuckRyder]

Grinding the lifter bore anything except round and in spec runs contrary to everything I've ever been taught or read about lifter bores..

If I'm understanding what you're saying correctly don't most lifters have a an area (I'll call it a "waist" for lack of a better term) that would accomplish the what your machinist is speaking of though?

[Bolted to Floor]

Thanks for the info.
I got the pressure gauge it haven’t had a chance to get back to the car. Hopefully I will later today or tomorrow.

[Falcon67]

Grinding the lifter bore anything except round and in spec runs contrary to everything I've ever been taught or read about lifter bores..

If I'm understanding what you're saying correctly don't most lifters have a an area (I'll call it a "waist" for lack of a better term) that would accomplish the what your machinist is speaking of though?

In the 351C world, if the bores aren't to spec, you can counter bore and press in bronze sleeves that are then honed to size.  Also done to limit oil loss in the lifter galleries because the mains are fed from there.  You don't want to bend a pushrod and toss out a lifter on the stock setup, you'll lose the mains nearly instantly.

[My427stang]

Back to the original poster.

Can you verify that your 12.5 lbs was idle oil pressure not at RPM?

If it was indeed 12.5 at idle, before you start considering a reblock or expensive lifter bushings, I would go with an M57HV pump and fix those two piddle modifications.  You started with a standard pump (short gear, then swapped to a M57B, short gear bigger spring)   You saw nothing, and you should have seen nothing, it's the same pump only when up on the relief would it have been different. Swapping to the M57HV you get the tighter relief, but you get a taller gear set that generally, and sometimes significantly adds idle oil pressure.

In fact, the pressure relief for both a M57B and M57HV are both 60-65 psi, so if you are seeing 70, there is some decent resistance there, don't give up on easy stuff yet

Lets say you get 5 psi with the pump and 5 with correcting bolt and feeze plug "fixes", you will be in a more comfortable spot, but honestly you might get more from the pump alone.  Then , not quite enough, try 10w40 or a mix of oil to thicken it up, although if running Morels can't go too much, I have dyno'd Morels on 15w40 with zero issues. 

You might be there with only the pump change, but I would do both the pump and the holes because I think they are silly and it's free oil pressure.  In all cases,  get a good gauge on there to get a real number

[C6AE]

Have you checked the orientation of the cam bearing oil holes?
I have seen plenty of these installed incorrectly...

[Bolted to Floor]

I think its got two .041 holes one in the plug and one in the cam retainer bolt plus the lifter bores.

Wayne, you are correct.

Back to the original poster.

Can you verify that your 12.5 lbs was idle oil pressure not at RPM?

Ross, yes, with the car was idling about 950 RPM oil pressure with the car at operating temperature was about 12.5.

Have you checked the orientation of the cam bearing oil holes?
I have seen plenty of these installed incorrectly...

C6AE, the short block came assembled from the machine shop. I hope he did them right.


Well…..I finally got a chance make a comparison on the gauges. I used my battery drill on the oil pump to compare the Autometer gauge in the car to the mechanical liquid filled unit I bought screwed into fitting for the oil pressure switch. Then took the mechanical liquid filled off the car to compare it to the gauge on my air compressor driven by the regulator.  It turned out to be a bust, I have no faith in any of them to know which one is accurate.

Autometer Gauge   Test Gauge   Air Compressor regulator    
25                                 30                        15   
50                                 58                        60   

Once I can get back to the office, I will have access to a gauge calibrated on a yearly basis to make a final determination.

While I had the timing chain cover off, I looked as best I could through the intake valley, which wasn’t very far to see if there was bleed off around the lifters. #5 cylinder was the only one I could see much of at all. I did take the time to turn the pump and look at the lifter, then rotate the engine over by hand, rinse and repeat. That one didn’t look to have any issues. I did notice oil flow coming out from the cam at the cam gear. I presumed this to be normal and never thought about a video until now!!

The cam plate retainer hole with a hole got a center punch to close it up then swapped it with the other bolt as a precaution. The plug behind the distributor was replaced. So, no more oil shooting at the back of the timing chain cover. Hopefully, that was the cause for 2 different front seals to leak.

Several of you guys had it right, eliminating the plugs with holes didn’t do much for idle oil pressure at operating temp.

It’s time for an oil change to a straight 30 weight and see what happens. I will cut the filter open to look for any signs of debris.

While it’s still mobile, I need to get my garage in order and start on a remodel project. Thanks for the help. I will come back to the thread when I have more information.

[wayne]

The front cam bearing has a small slot to oil the cam retainer that's what you see their its ok

[My427stang]

I think you'll gain oil pressure with an HV pump...maybe give Doug Garifo a call and see what he thinks, but I like the HV for just that reason, every turn of the pump displaces a more oil with the tall gears.  Until you get to relief spring pressure, that's what the engine sees

[Bolted to Floor]

Thanks Guys.

[C6AE]

C6AE, the short block came assembled from the machine shop. I hope he did them right.

I would want to know, it is not uncommon to find them installed (incorrectly) with the holes up, which is a clearance issue.