Author Topic: High oil pressure  (Read 3515 times)

Offline Edorsett

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High oil pressure
« on: April 21, 2020, 08:04:24 PM »
I have a 1980 GMC Sierra grande with a 350 sbc and when I start it the oil pressure gauge is in the middle and after awhile this is where it ends up. What could cause this?


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Offline bd

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Re: High oil pressure
« Reply #1 on: April 21, 2020, 09:18:02 PM »
It is highly unlikely that at any defined, fixed or otherwise given engine RPM, the oil pressure would increase with an increase in temperature.  Hence, begin by verifying the actual oil pressure using a 100 PSI mechanical pressure test gauge, preferably tee'd off of the same oil galley as the factory sender.  Then as engine temperature changes compare the pressure indications of both gauges.  Once you've established a known baseline you can begin determining the cause of any differences.
Rich
It's difficult to know just how much you don't know until you know it.
In other words... if people learn by making mistakes, by now I should know just about everything!!!
87 R10 Silverado Fleetside 355 MPFI 700R4 3.42 Locker (aka Rusty, aka Mater)

Offline Edorsett

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Re: High oil pressure
« Reply #2 on: April 21, 2020, 09:27:35 PM »
Ok thank you I will try that.


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Offline bd

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Re: High oil pressure
« Reply #3 on: April 22, 2020, 12:26:09 AM »
BTW - oil pressure between 30 and 60 PSI for a stock engine is excellent, 30-35 PSI being quite common.  Once you've verified oil pressure using a proper test gauge, more precise help can be provided.
Rich
It's difficult to know just how much you don't know until you know it.
In other words... if people learn by making mistakes, by now I should know just about everything!!!
87 R10 Silverado Fleetside 355 MPFI 700R4 3.42 Locker (aka Rusty, aka Mater)

Offline Edorsett

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Re: High oil pressure
« Reply #4 on: April 22, 2020, 08:17:06 AM »
Ok thank you


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Offline JohnnyPopper

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Re: High oil pressure
« Reply #5 on: April 22, 2020, 04:07:05 PM »
Is it electric or mechanical?

If it's electric your circuit may be affected by 'heat' as in poor B+ connection or ground.
1957 Apache 3100 235 Inline 6, 3 on the tree
1973 C-20, 3+3 454 4BBL TH400  Water Injection
1978 K-10, 350 4BBL TH350 NP203 M.M. Part time Kit/Hubs
1980 C-10 under construction

Offline Edorsett

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Re: High oil pressure
« Reply #6 on: April 22, 2020, 05:00:53 PM »
Ok thanks!


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Offline Edorsett

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Re: High oil pressure
« Reply #7 on: April 22, 2020, 07:36:50 PM »
Lol I did not wait long enough it went to the middle when it got up to operating temp sorry my bad


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