Break-in gone wrong!

[Cameron Koehn]

Originally Posted by pistonbroke

Ok. I've been following this thread from the beginning but held my tongue. I know its unlikely but when the pump gear gets up to running temp could it spin on the shaft under load then cool off and seem normal when removed and visually inspected. I'm referring to the gear on the shaft that actually moves the oil in the bottom of the pump. Tim

Yes I had thought of that too, but unless it happened to stop at precisely the right place, the picture I posted is current and the gear is peened to the shaft. If it had spun, it would be unlikely that the peen still lined up.

[cadillac512]

Originally Posted by Tim Ayers

Not a bushing, but a plug or grub screw to block or close that hole off. Without the push rod in place, oil will be forced through that hole. In a stock set-up, the push rod would cause resistance to the flow of oil through that hole. Now there is nothing stopping it.

Tim, he had pressure for several minutes' running, then none on a restart.

[Cameron Koehn]

First start had 40 psi. Same for the next 4-5 runs.

[Cameron Koehn]

I checked and there is no modification for 90% oil filter.

Follow my logic. If the pump pumps oil when I turn it by hand, and the cam and gear turn when I hold them with a wrench and turn the crank, and the pump gears have not appeared to spin on pump shaft, and the oil pickup is stock with no pinholes, ...oh maybe the bypass is opening at a super low pressure so that when I turn by hand I get flow, but when installed and pumping against pressure, it bypasses?

[Cameron Koehn]

IMG_20240408_140551189.jpg

What is the stock (factory) bypass pressure? And would i just shim the spring for more? Not saying this one's bad, just wondering.

[Lawrie]

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even if the relief valve was stuck open there would still be oil in the gallery
when cranking, as it has to go past the gallery to get to the relief valve.
Lawrie

[Cameron Koehn]

Not on an 8ba. The ONLY relief is on the pump itself. Unless I'm off my rocker.

[cadillac512]

Originally Posted by Cameron Koehn

Not on an 8ba. The ONLY relief is on the pump itself. Unless I'm off my rocker.

You are correct.

[Tim Ayers]

Originally Posted by Cameron Koehn

First start had 40 psi. Same for the next 4-5 runs.

Ah, right.

[Ziggster]

Some good info from Mac VP in post #10.

https://www.fordbarn.com/forum/showt...1316&showall=1

[petehoovie]

Originally Posted by Ziggster

Some good info from Mac VP in post #10.

https://www.fordbarn.com/forum/showt...1316&showall=1

Re: About oil pressure relief springs- Again
In the science of hydraulics, pressure will be constant throughout any closed system.....regardless of the distance from the pressure generating source (i.e. the oil pump). If there is a pressure relief opening (controlled by a spring loaded valve) the excess pressure will bleed off through this valve. Since the pump is capable of building more than enough pressure, the relief valve will be constantly bleeding off this pressure as long as the pump is running.

If you have two pressure relief valves, but they have different spring loads, the oil pressure will push against both simultaneously. What will happen is that the oil will bleed off through the lower rated pressure relief valve. The higher loaded spring in the other valve will continue to hold itself closed. So even if you have two or more relief valves, the system will seek its relief through the lowest spring load.....always.

As for our old flathead oil pumps, all the original Ford pumps (1932-47/48) did NOT have a built in pressure relief valve as part of the pump itself. Ford designed the system with a separate relief valve, engineered in the oil gallery line....the tube running from rear to the front in the valve chest. The early V8's had a 50 psi relief spring in there. Beginning in 1941 they changed the spring rating to 80 psi and it received a new part number. At the same time, Ford also changed the oil pressure sender unit to the 80 psi rated unit to match up to the new system rating.

Unless your older (32-48) oil pump is still in good operating condition, you would have to replace them with the latest version pump, which was the 8BA type. You can't buy those older pumps or kits for them anymore. The new style pump has one additional feature....it has its own built-in 80 psi relief valve.

So when you use this pump in the older motors with the separate relief valve up front, you can either remove the spring and plunger from this location, and put the hex plug back in place, or simply leave it all intact. I would change out the spring to the 80 psi type to match up to the 80 psi type in the oil pump.....if your sender unit and gauge are the 80 psi rating. Otherwise I would use the 50 psi spring.

We have both springs in stock. For some reason they are not listed on our website. I will fix that later today.
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Office: 513-724-9486
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[Ronnieroadster]

[QUOTE=petehoovie;2303344]Re: About oil pressure relief springs- Again

So when you use this pump in the older motors with the separate relief valve up front, you can either remove the spring and plunger from this location, and put the hex plug back in place, or simply leave it all intact. I would change out the spring to the 80 psi type to match up to the 80 psi type in the oil pump.....if your sender unit and gauge are the 80 psi rating. Otherwise I would use the 50 psi spring.

We have both springs in stock. For some reason they are not listed on our website. I will fix that later today.
_

I think you wrote something wrong.
If you remove the spring and plunger and then put the hex plug back on your going to have a big hole at the end of the oil feed tube creating a good sized oil leak. If the plunger is removed the hole where the plunger sits needs to be closed.
Ronnieroadster

[pistonbroke]

Cameron I may be wrong but I was told here on the barn that 8ba's had 80 psi systems from the start so if that's true your 40 or 50 psi on a fresh engine would indicate a problem from the start to me. God forbid but I have seen the galley tube fail on a 8ba and that could cause a similar problem but you would still see oil at the port in the back of the block I would think. How long did you crank on it with the gauge out? With the system open to air the oil would drain back down and with the gear reduction it would take a bit of cranking to get oil up again. Tim

[flatjack9]

The pump generally relieves at around 60 psi.

[tubman]

My 1953 Motor manual says the relief valve opens at 57 psi. That's close enough to what "flatjack9" says to probably be right.

[flatjack9]

I've tested many and there is some variation. 55- 60.

[tubman]

Originally Posted by flatjack9

I've tested many and there is some variation. 55- 60.

As one would expect with any analog mechanical device.