QuestionQUESTION: When I first start my TR6 it has very high oil pressure (100psi), particularly when its cold and the oil is still thick. I noticed that my car has been fitted with a part designed to feed oil to the rocker shaft, and I believe this might have taken the place of oil pressure valve? I am not sure that this represents a problem I need to worry about?
ANSWER: The oil feed to the rocker shaft is a standard "fix" some people do to improve the oiling to the rocker shaft and rockers. It does not replace the pressure relief valve. This line to the rocker shaft should start from one of the oil gallery holes on the driver side of the engine, and if so, you are OK.
The oil pressure relief valve is the large nut that protrudes at the bottom of the block, driver's side, directly below the distributor pedestal and to the left of the oil filter.
at 100psi cold, I would ask what viscocity oil are you running; 100psi is on the high side of oil pressure cold at idle, and you are likely bypassing the oil filter until the pressure drops.
I would also look to verify the oil pressure by measuring with another gauge to make sure 100psi is accurate.
Hope that helps
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QUESTION: I am running 20w50 oil. I will check the pressure with another gauge.
AnswerOK. Also look at what is the hot oil pressure at idle, and when at 3,000 revs. You don't say if you converted to a spin on filter, or have the stock setup, a clogged oil filter might also be a source of high pressures.
The oil pressure relief valve may also be stuck, such that it doesn't open to bypass the pressure, so it may be worth it to pull, examine, clean that as well as a precaution.
Verify the pressure first, and then go from there to eliminate possible causes. It may just be that your pump and bearing clearances are that tight..
