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Low oil pressure at operating temp

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Old 03-03-2014, 02:59 PM
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Low oil pressure at operating temp

Just as the title says I am having trouble getting low oil pressure after the engine reaches operating temperatur.

I rebuilt my engine 3years ago changing all the bearings and installed a high flow oil pump. After that rebuild my stock gauge showed around 60+ PSI at cold engine (idle RPM)

After the engine warmed up it showed around 50PSI at idle RPM.

But lately it just started showing lower oil pressure. No noises and no smoke, oil-loss etc.

It is curently showing around 45PSI at cold engine and about 15PSI at normal operating temperature.

I thought is could be the pick-up at the oil pump so I actually removed the engine to do a complete inspection, but the pickup and the oil pump is just as it is supposed to be.

Any other ideas?

Btw, the engine is going to be repainted anyway so the engine removal work had to be done anway
Old 03-03-2014, 03:25 PM
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Re: Low oil pressure at operating temp

Have you been using same weight oil? How has it been driven last few years?
Old 03-03-2014, 04:36 PM
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Re: Low oil pressure at operating temp

i hear spun cam bearings will also take the oil pressure.
Old 03-03-2014, 07:48 PM
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Re: Low oil pressure at operating temp

With no noises, cam bearings are the most likely cause of low oil pressure when hot. Bad rod bearings make noise. Bad main bearings normally seize up.

Confirm pressure is low with a mechanical gauge first.

What kind of mileage is on the oil filter? Replace it even if the oil doesn't need changing. Cut open the filter. Dig out some filter material and put it in a vise to squish the oil out of the material to make inspection easier. Lots of metal is a good indication some bearings are failing.
Old 03-07-2014, 03:21 PM
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Re: Low oil pressure at operating temp

Originally Posted by Orr89RocZ
Have you been using same weight oil? How has it been driven last few years?
I am currently runing synthetic oil. I use the stock weight grade 5W-30.

Sorry the slow response from me here..Have been very busy at work lately.
Old 03-07-2014, 03:27 PM
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Re: Low oil pressure at operating temp

Originally Posted by AlkyIROC
With no noises, cam bearings are the most likely cause of low oil pressure when hot. Bad rod bearings make noise. Bad main bearings normally seize up.

Confirm pressure is low with a mechanical gauge first.

What kind of mileage is on the oil filter? Replace it even if the oil doesn't need changing. Cut open the filter. Dig out some filter material and put it in a vise to squish the oil out of the material to make inspection easier. Lots of metal is a good indication some bearings are failing.
The oil I am using now is stock weight grade. Have recently changed the oil and filter. Using synthetic oil 5W-30.


Ain't many miles on the oil filter at all. I suppose the cam bearings are good since they have around 5-6000miles at them.
The car is not used for race though but more like a daily (Nice weather) car. But of course I do push the car a little

I think I would have to check with another gauge.
Cause I can't find anything suspicious when I dropped the oil pan and neither in the oil.
Old 03-07-2014, 06:30 PM
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Re: Low oil pressure at operating temp

Originally Posted by camaro87-alex
I suppose the cam bearings are good since they have around 5-6000miles at them.
Doesn't really mean much. One still could have spun in the block and is causing problems.
Old 04-21-2014, 08:51 AM
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Re: Low oil pressure at operating temp

Finally got the engine in a engine stand and removed the camshaft today to check the bearings. They all look nice and they all look like they are in correct place. Mayby one of them have the oil hole a little out of center but if I don't remember wrong,

arent there oil grooves inside the cam bearing bores???
I mean this shouldn't effect the lubrication since the grooves are filled with oil anyway.
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