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Old 12-29-2005, 08:50 PM   #1
ratrod67
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Oil pressure problem-Excessive PSI

I'm having some Oil pressure problems with my 509ci BBC. I had the motor running fine in a 71 Camaro, sold the body and installed the motor in a 72 truck. No changes to the motor at all. Started the motor for the 1st time in the truck and noticed my oil pressure was pegged at 100 psi. Shut it off imediately. Looked on the ground and saw about 5 quarts of oil. Filter was tight so I checked the oil filter adapter. Looked ok so I reinstalled it and tried again with a new filter. Same thing. 100 psi and oil on the ground. I figured the filter got bumped or maybe the adapter was bad so I went and bought another. GM parts guy said to install it with no RTV or gasket. Oil filter adapter straight to the block. Started the motor and same thing. 100 psi and oil everywhere. It's leaking from the top of the filter. Not spraying but like it's overflowing out and falling straight down. I made sure the bolts weren't too long and bottoming out and it's not coming out from higher up the motor. I had someone else start the truck while it was on jackstands and watched it flow out of the top of the filter. Also made sure I'm using the right filter as well. The adapter I'm using is part # 3952302 and filter is a Fram PH25. Any ideas?
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Old 12-29-2005, 09:03 PM   #2
cableguy0
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Re: Oil pressure problem-Excessive PSI

theres a clog somewhere.fram isnt the greatest filter to use anyways but it shouldnt cause that problem normally they cause lower oil pressure. go get a wix or purolator. its hard to say what might be causing your problem.if its a high pressure pump is it possible the bypass spring is stuck?
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Old 12-29-2005, 09:30 PM   #3
Longhorn Man
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Re: Oil pressure problem-Excessive PSI

Can't help on the oil pressure issue, but I'll second the comment on fram, they make the worst filter on the market.
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Old 12-29-2005, 09:46 PM   #4
Guardrail
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Re: Oil pressure problem-Excessive PSI

Interesting.....The leak may be caused by the bolts that hold the filter adapter to the block. You mentioned the bolts are not "too long". However some have overlooked that regular bolts have hex heads that are "too tall". If you remove the filter and look at the face of it, you may see gouges from the bolt heads. If so, the filter is tightening against the bolt heads instead of the o-ring seal. Hence a big leak.

This could be combined with another anomoly. Is the oil pressure gauge the same one you were using before? If not, it could be a bad gauge. In order to peg a 100 psi gauge when the oil is hot, the relief valve inside the oil pump would have to be stuck. That doesn't happen too often though. (Never seen that).

Just trying to give you some idea's to chase down.....
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Old 12-30-2005, 08:01 PM   #5
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Re: Oil pressure problem-Excessive PSI

Quote:
Originally Posted by Guardrail
Interesting.....The leak may be caused by the bolts that hold the filter adapter to the block. You mentioned the bolts are not "too long". However some have overlooked that regular bolts have hex heads that are "too tall". If you remove the filter and look at the face of it, you may see gouges from the bolt heads. If so, the filter is tightening against the bolt heads instead of the o-ring seal. Hence a big leak.
Turns out the filter was listed in the Fram catalog as being for a BBC but was really for a 350 ci deisel motor. Jackasses. Last time I EVER buy Fram. Got an AC Delco filter and problem is solved. If you look at the pic you will see the difference in the size of the gaskets on the filters. The Fram gasket was tightening against the bolts that hold the adapter on and not letting the filter seal against the block. Not really sure why the gauge was pegging to 100 psi but it's now about 60 when I start the truck up and about 30 when fast idle kicks down. Thanks for everyones help!
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Old 12-29-2005, 10:03 PM   #6
Longhorn Man
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Re: Oil pressure problem-Excessive PSI

at 100 PSI, would the oil even go to the filter? It should bypass at 60 shouldn't it?
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Old 12-30-2005, 11:59 PM   #7
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Re: Oil pressure problem-Excessive PSI

glad you got it sloved with out haveing to pull the motor apart
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Old 12-31-2005, 12:16 AM   #8
Longhorn Man
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Re: Oil pressure problem-Excessive PSI

Yet another example on why fram sucks.
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Old 12-31-2005, 02:00 AM   #9
72MARIO
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Re: Oil pressure problem-Excessive PSI

Hey you know what cool ?

If you buy a whole flat of A/C filtersfrom GM they sholuld be able to sell you a whole flat really cheep For a 350 they are $2 cheeper a piece than buying them seperate. All of my trucks use the same filter and every 5000k's they want a new one.
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Old 12-31-2005, 02:38 AM   #10
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Re: Oil pressure problem-Excessive PSI

I bought a crap load of A/C Delco filters from K mart for $1.00 each. They where for SBC but should work on a bbc to??
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