Extreme oil pressure.

[R.Smith]

Problem: when I start my new bump on cold mornings (25 degrees)the oil pressure pegs the guage at over 100psi for about 30 seconds.I noticed it when it blew the oil filter seal, so I put on a new filter and chalked it up to not tightening the filter. The next time I started it at a low temp it blew the filter apart at the seam! And, of course, coated the fender well with 3 quarts in about 3 seconds.

The oil is 10w 40. The pump check valve seems to work eventually...pressure falls off after about 30 seconds of idling.

Any suggestions that don't require dropping the pan and replacing the pump? (I know...but I can hope)

I've already put a quart of Marvel Mystery Oil in it.

[averagef250]

What engine? oil filters are only supposed to see 70 PSI max, they burst not much over 100.

[DBossMan]

Depending on what engine you have, you might try the Ford FL-1HP filter. Here's the description from the motorcraft site:

High-Performance Racing Oil Filter

The FL-1HP combines the unique filtering technology of the Motorcraft® FL-1A with a new canister design for high-performance auto racing. The FL-1HP is a single stage full-flow filter capable of handling the high oil flow rates of today's racing engines. Premium quality filter paper allows the FL-1HP to perform under some of the hottest racing temperatures. The base plate design provides full oil flow under high rev conditions. The heavy duty oil filter canister will withstand burst pressures of up to 400 PSI. The FL-1HP fits Ford, Chrysler and import cars wherever a Motorcraft® FL-1A filter is recommended.

I use these on my Boss 302 Mustang which sees some pretty high oil pressures under racing conditions. You can pick them up at your local ford dealer.

Tim

[papabug71]

Yup. Need more info.

It could be anything from a 240 I6 to a 390 V8.

[fordman]

i think the main issue is why is the pump putting out that kind of pressure. it has to be stuck some how. maybe the relief valve. or something. that hp filter should help until you have time to fix it.

[Dragon]

I have put High Volume pumps in engines and cold the clearances are so tight and the oil being thicker that a non high pressure but high Volume only pump would hit 160. I used a side oiler pump in one of my 428s and they do not have a pressure relief because the side oilers relief is at the back of the cam oil gallery. Cold on that engine with 50 weight was 210 at 1400 rpm lope idle.
Have you tried thinner oil?

[R.Smith]

Thanks for the tips.

The engine is a 390. The truck sat for 3 years and was only started occasionally. The guy I bought it from said he changed the pump when he rebuilt the engine but didn't put anything special in it...just a stock pump. I noticed that the oil pressure would peg the guage at 100 for about 20 seconds before dropping off on the days that the filter didn't explode. I think now that this was the bypass valve sticking.

Yesterday I put a bottle of Marvel Mystery oil in with the oil and drove it about 20 miles. This morning the oil pressure hit about 60psi when I started it (25 degrees outside). Hopefully thats the valve working properly. Pressure stayed up good on the drive to work.

[Dragon]

That is more normal my 360 would do 60 any morning and and drop to 20 at an idle when warm.