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Discussion Starter #1 (Edited)
Alright guys. I need a lil help. Typically my oil pressure usually reads high but was told not to worry about it till it starts to get above 100psi. Lately it's been doing so.

Engine: JDM Ej205 with around 50-60k
Oil: Motul X-Cess Clean+ 5w-30 full synthetic
Gauge: Mechanical, hooked up in factory location under alternator

I've had my mechanical gauge looked at by a mechanic and he even hooked up his electric gauge to ensure mine is reading correct.

Cold start/idle: 80-90psi
Let idle to warm up for 10 min, coolant at operating temp, driving like a grandma (staying under 3k rpm) and staying out of boost: 110-115psi 馃槵
Warm/hot idle: 40psi
Warm/hot cruising @ 2k rpm: 87psi
Warm/hot cruising @ 3k rpm: 96psi

I've heard several conflicting things.
Should I move gauge location and see if I get a different reading before assuming my pressure relief valve on my oil pump is done for and needs to be replaced?
N what other location gives an accurate reading?

Thanks for the help in advance y'all! 馃檹
 

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The correct way to measure oil pressure is to remove the oil pressure switch from the cylinder block and connect a gauge there.

If the engine oil temperature is 80 掳C, then the correct oil pressure is:

800 rpm -- over 1.0 kg/cm2 or over 98 kPa
5000 rpm -- over 3.0 kg/cm2 or over 294 kPa

To reinstall the oil pressure switch, use a torque of 25 Nm.

The manual gives no indication of what oil pressure reading is considered excessive.

However, the oil pressure relief in the pump body ought to open at 580 kPa.

I think you don't have to remove the pump to check the relief, or even to fix it -- but it's been many beers since I was staring at one so I may be hallucinating. If memory serves though you can eyeball the bottom of the oil pump; there will be an angled allen bolt that is positioned differently to the others. Behind that bolt is a metal ring and a spring with a plunger thingy. High pressure opens a gap that lets oil flow back into the pump. Those surfaces need to be really smooth and if there is a scratch or burr or debris in there, the mechanism may jam shut and oil pressure may build up.

If you decide to do this note that I do NOT know the torque for the allen bolt that holds the bypass onto the pump, and have never met anyone that does. Try guessimating by reversing a torque wrench to remove the thing, marking it for reference, attending a s茅ance, or something (?).

There were issues with some later pumps getting their bypasses stuck but the bugeye pumps should still be working fine even after all these years I think.

Incidentally, have you seen that others are experiencing the same oil pressures as you on healthy motors? Could it be that what you are measuring is OK?


In fact more than one person in the past has had the same question and the answer was "it's normal." For example:


Do those numbers look like yours? Are you experiencing high pressure-related problems?
 

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Discussion Starter #3
@SD_GR Yes and no.
Cold idle is around 80-90psi while others are at 90-100psi.
Warm/hot idle sits at 40psi which is similar to others, though some others do see as low as 30-35psi.
Here's where I'm concerned: After a cold start and letting it warm up for 10min I start to drive, staying out of boost and under 3k rpm. While driving like a grandma it rises to well above 100psi. It gets to 110-115psi.
Once fully warmed up, cruising at 2k rpm I'm at 85-87psi where others are 70-80psi.
3k rpm I'm at 95-97psi while others are 80-90psi.
Fully warmed up WOT is 100psi which matches others..

I'm not sure if it's normal or not because of how close my numbers are, yet they're slightly off. N going well above 100psi when driving like a grandma is very concerning...

Not sure what my next move is to figure out of it's an issue or not.
 

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I don't know what to tell you either, sorry.

Are you seeing any seal failures? Is there oil seeping out of the engine due to high pressure?
 

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Discussion Starter #5
I don't know what to tell you either, sorry.

Are you seeing any seal failures? Is there oil seeping out of the engine due to high pressure?
I've had a power steering line blow up due to my turbo eating a whole through it. Major fuel leaks you name it. If there's an oil leak there's no way I'm finding it.. 馃う鈥嶁檪锔
 
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