oil pressure

V4F

V4F

Well-known member
I had a guy ask me how long it takes to get oil to the mains on stock "A"

his report --- but we can't get that oil pressure hole screw out while in the car even with carb etc. off (it's been rounded off in slot and is stuck solid).
Do you know if the time to get oil to all chambers (and therefore all main bearing tubes) is written anywhere, so we can understand if this engine is pumping enough to do that job. We ran it once for over 3 minutes and there was very little in the back chamber by then.
I know it's usually all happening behind a steel panel, but thought somewhere it would be written what the original specs were, so that we can compare it to that.
If not, I know we will have to pull down and start checking everything, but it was driving nice and except for the ticking, we believed it was all OK and was going to let her keep driving. When we saw how long it was taking oil to get into the 3 chambers we don't think it's safe to bolt all back up and drive.

any help greatly appreciated ............. steve
 
If all you say is correct, then you need to get a copy of Restorer magazine jan-feb 1998, pg 22.
carry on
 
In about 1 1/2 min. I had oil coming out the lower part of the drain back tube! The model A oil pump is a high volume pump, you should a had a mess after 3 min’s run time. My rebuilder said to leave the drain back tube loose at the lower part to see if I had oil flow!
 
Do as Big Hammer says. I bought a speedster several years ago, with a very tired engine. After sitting overnight the mains pounded like crazy for about a minute until oil got to them. I never timed it but am estimating about a minute. Even if an oil pressure gauge is in that hole, it wouldn't tell you when oil got to the mains. That engine also left a huge trail of oil, coming from the rear main area.
 
Interesting question. Whenever I have pulled my valve cover there was always a certain amount of oil in the chamber. I always figured that was enough to lube the bearings until a fresh supply arrived.

I also run a full flow oil filter so there is always oil "up there".

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Depends on how long it has sat not run. From the valve galley, there are tubes that go down to the mains. the oil fills the valve galley and then oil fills the tubes. If the engine was sitting not very long it would take a while for it to drain out. As for filling the galley, it would only take seconds to fill as the standard pump pumps 1 gallon and one pint per minute.
 
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Why did he bring this up in the first place? Seems to me that there was no problem, until he made one.

Besides, oil pressure has nothing to do with pumping 'enough' (volume).

It ran fine? There's oil in it? Go!

For other folks who are trying to remove the oil screw: the oil screw was rounded and tight on mine also. I got a good screwdriver and wedged it tight between the frame and screw.
 
Model A's are very forgiving . He probably heard bearing rattle and was wondering if oil was getting to the bearings quick enough . as for the oil screw I've used heat around the screw and they came out without as much effort . I always did this with the engine out for overhaul .
 
I installed guage near choke rod in hole already in firewall. Used brass bulkhead fitting and can see easily while driving. While cranking guage reads 5# and goes to 15 at start for 30 sec and slowly drops to 2-5 at operating temp.plenty of oil!20160519_101153.jpg
 
There is a little known thing that can cause a problem with oil level in the valve chamber.
If you look at the "dam" ahead of the oil tube, where splash over lubes the timing gear, you will likely find it eroded down into a rounded looking shape. Ford blueprints show this dam is supposed to be straight across the front ahead of the oil tube. Too low and too much oil will splash over and starve the lifters and main bearings.
 
Ok Glenn, If it is true that the oil dam in the valve chamber is suppose to be straight across, Then I have a problem, because mine is curved down and jagged. Can you or someone tell me how high it should be, and how to repair it. I thought I read somewhere on this forum that that was normal. I am sure mine wasn't worn or eroded, it sure looks like it was made that way, but if I am starving my mains, I want to try to fix it. I have had real good luck with JB weld for engine repairs, so could probably put a patch on with that.
 
oldforder said:
Ok Glenn, If it is true that the oil dam in the valve chamber is suppose to be straight across, Then I have a problem, because mine is curved down and jagged. Can you or someone tell me how high it should be, and how to repair it. I thought I read somewhere on this forum that that was normal. I am sure mine wasn't worn or eroded, it sure looks like it was made that way, but if I am starving my mains, I want to try to fix it. I have had real good luck with JB weld for engine repairs, so could probably put a patch on with that.
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Mine is also as you describe and you can see in the photos post #6 above that i have plenty of oil.
 
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