Low oil pressure.

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Rjonesy
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Low oil pressure.

Postby Rjonesy » Tue May 29, 2018 4:30 pm

Recently as the temps have risen well into the 90’s my oil pressure light will come on at idle. I changed out the 10w30 for 15w40 and same result. I’ve also got a gauge and it is pretty low at idle. Pressure is fine at any revs above idle. Do I have anything to worry about?

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Duck
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Re: Low oil pressure.

Postby Duck » Tue May 29, 2018 6:50 pm

pressure relief valve sticking, maybe? or a broken spring?
90 Dakota with C223

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Rjonesy
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Re: Low oil pressure.

Postby Rjonesy » Wed May 30, 2018 8:45 am

Hadn't been aware of the oil pressure relief valve. Did a search and will check it out. I suppose at this point if the spring is weak or broken the only option is a Rube Goldberg attempt to find a matching spring. I spent about an hour this morning looking through my factory shop manual. Very poorly written. It shows the relief valve on the same page as the oil distribution rail inside the oil pan. I was freaking out about that! After searching this sight I see that it is located on the oil cooler. Haven't done a physical inspection yet as work was calling. Is it reachable without removing the cooler from the engine?

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Rjonesy
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Posts: 92
Joined: Wed Feb 01, 2017 11:46 am
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Re: Low oil pressure.

Postby Rjonesy » Wed May 30, 2018 8:46 am

BTW - I do have the turbo and found one reference that the turbo shaft lacks lubrication below about 30 psi.

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Duck
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Re: Low oil pressure.

Postby Duck » Wed May 30, 2018 4:11 pm

might find the whole filter base / regulator , used somewhere
90 Dakota with C223

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puttputtinpup
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Re: Low oil pressure.

Postby puttputtinpup » Thu May 31, 2018 3:42 am

I'd put a mechanical gauge on it and see what it looks like. I heard of plenty of pressure swnders hetting weak and registering low. 2 of them were my own. I realize the gauge runs off a different sender, bht id double check the actual oressure before tearing things apart. My $.02 worth

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Rjonesy
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Posts: 92
Joined: Wed Feb 01, 2017 11:46 am
Location: 75150
Isuzu vehicle(s): 1986 Turbo Diesel Space Cab LS
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Re: Low oil pressure.

Postby Rjonesy » Tue Jun 05, 2018 7:42 am

Solution!!!
The shop manual lists several possibilities for low oil pressure. One being compromised filter media. I changed the filter and - yea!!! No more low pressure. It was a Wix filter, which I've been using. New one is the same. Hopefully just a weak sister.


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