32 Sedan Plodder Flatty. Will packing the relief valve improve idle oil pressure?

[Mart]

I heard it mentioned that packing the pressure relief valve can improve oil pressure. This motor has low oil pressure when idling hot. Will it help? Join me for a bit of Sunday afternoon tinkering.
Recorded just last weekend. Not a retrospective.

https://youtu.be/kRzCvq304X4

[mfirth]

Too bad Mart, sure had hopes for better. It is a good sounding ole plodder though.
Cheers

[deuce5wndw]

Hey Mart, I think your problem lies with excessive clearance on your bearings. Have you ever plasti gauged the bearings? Is this the engine you put together and reused the bearings? Sorry you play musical engines, so I lost track which one this one is! lol

[Russ/40]

Mart, are you running a 40lb pump, or an 80lb pump.

[Mart]

I believe it is an 80lb pump. It has the built in pressure relief valve. The pressure was peaking at over 80psi when first started. I have plans for one last attempt with this motor. In truth it would benefit from a rebuild, but it's not economically viable. It runs great and is capable of providing good service within it's own limitations.

[Bored&Stroked]

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Find a set of rod bearings that have a slight oversize on them (on the OD), that might work. Not sure if there are ones that are .030 undersize on the journals and .002 oversize on the rod bore?

[Mart]

Something like that would help for sure. I can't see it happening though. People over here just don't have buckets of them floating about. (floating - geddit? lol.

[Russ/40]

I would try an 8BA pump. The one you used doesn't look like the 8ba one.

[aussie merc]

a pressure relief valve is exactly that it should only open to dump excess pressure back to the sump by all means check the seat and make sure its sealing correctly as a small leak will have a dramatic effect on oil pressure especially at idle

[69a]

Originally Posted by aussie merc

a pressure relief valve is exactly that it should only open to dump excess pressure back to the sump by all means check the seat and make sure its sealing correctly as a small leak will have a dramatic effect on oil pressure especially at idle

X2. If you use a 12" wrench to close the faucet in the kitchen, does it give you more pressure in the bathroom?

[Adam/Mill Valley CA]

Mart, you and I had communicated about this issue by PM. If you recall, my poured bearing motor was showing zero psi at idle after a long freeway run, and about 18 psi at speed. Main bearings showed .0035 thou clearance. Replaced a no-name offshore 8BA style pump with Mellings M-15 hi volume pump (8RT pickup). Now, 45 psi at speed, 15 psi at idle after a long hot freeway run. Front valley relief #50 spring was shimmed 1/4". No excessive leak from the back labyrinth main seal. This is with Valvoline 20/50 VR-1 oil, I will change to a 10/40 oil for cold weather driving (cold meaning 40 degrees here in the SF Bay Area). Will this extend the life of this motor, which runs really well, cruising at 55-60 mph on the freeway? I have no idea, it just may be treating my psyche-will report back further when I have a few thousand additional miles on it.


Adam

[tubman]

I had the same experience with the offshore oil pumps.

BTW, I have never found a Ford specification for running oil pressure. I bought a 1953 Edition of Motor's Manual, and it shows 8BA maximum pressure to be 57 psi.