Why is my oil pressure so high? (1 Viewer)

[deaddrift]

I don't know how long it's been like this, but my oil pressure at idle (~650 rpm) is at the H line when cold and more than halfway up the dial when hot. Under load I am above the H line at 1500 rpm, if I get to 2000 I am all the way at the top of the dial, similarly lower pressure when hot.

I am using the same Delo diesel oil I've used before. I had the engine slightly overfilled but now it is down just below the Full line on the dipstick. I only have the factory gauge, no numbers to attach to this.

Why might this be happening? How concerned should I be? What are my next steps?

Thanks mudders.

 

[canucksafari]

You need to first confirm the pressure readings with a mechanical gauge. It is possible/likely that the sender on your electrical gauge is shot.

 

[DanB]

Pressure Relief Valve

The oil pressure relief Valve can get stuck due to ware. This would cause the high pressure and could cause your oil filter to blow up. It is on the exhaust side of the motor towards the front down by the oil pan. It is a 22mm bolt. The best way to get the plunger out is with a wooden dowl, there is a hole in the backside of the plunger.
Dan

 

[deaddrift]

So drain the oil, remove the relief valve and check, meanwhile install a mechanical gauge. I will search threads to get an idea of how to do the second; I am a real one mechanic.

Advice and tips very welcome, thanks for the ideas so far.

 

[Gengis]

You won't need to drain the oil, just a pan fro drips should be fine.

 

[blis]

Most likely case is that your sender is busted and showing funky pressures... But as others said, feel free to check the relief valve---

 

[maat]

your oil pump has ADHD, throw some ritalin in with the oil

 

[asutherland]

You need to first confirm the pressure readings with a mechanical gauge. It is possible/likely that the sender on your electrical gauge is shot.

This.

Even before you do anything else, just check it with a mechanical gauge. If you don't want to permanently install one, you can buy a cheap one at an automotive store. I bought one for $10.00. Hook it up in place of the oem electrical sender unit, test against the FSM specs.

FWIW my oem gauge was showing exactly what yours is. When I tested with the mechanical gauge against the FSM, it was higher than I expected but still perfectly within the FSM specifications.

 

[slowandsteady BJ]

This.

Even before you do anything else, just check it with a mechanical gauge. If you don't want to permanently install one, you can buy a cheap one at an automotive store. I bought one for $10.00. Hook it up in place of the oem electrical sender unit, test against the FSM specs.

FWIW my oem gauge was showing exactly what yours is. When I tested with the mechanical gauge against the FSM, it was higher than I expected but still perfectly within the FSM specifications.

Andrew, I didnt know you had one of those? I'd sure like to borrow that one afternoon and check my pressure. Your solution for the OP is helpful but I like maat's answer beter.

your oil pump has ADHD, throw some ritalin in with the oil

Definitely.

 

[deaddrift]

So I think that maybe this is a useful thread for me to refer to...

https://forum.ih8mud.com/diesel-tech-24-volts-systems/607816-oil-presure-sensor-thread-pitch.html

My problem is that I'm tangling with the baseline engine lubrication system and I am a complete noob, especially about engines. I don't think the FSM will walk me through installing an aftermarket gauge and I need all the help I can get.

How do I set up the T fitting to keep the factory gauge functional so I can use the mechanical gauge as a reference against the factory? Plus the new gauge itself? And I can maybe get all this stuff at NAPA or Baxter?

How the heck should I be wiring this thing so it will work and be visible at night?

No clue here, gentlemen. And if I had any ritalin I'd be taking it myself. Can't emphasize strongly enough my lack of mechanical know-how.

 

[canucksafari]

Either buy or borrow a mechanical gauge. Usually all you have to do is spin out the oem sender and spin in the mechanical fitting. If they are not the same size, then take the sender to your auto parts store and have them give you the correct fitting. You are only hooking up the mechanical gauge temporarily. If you have any doubts or just don't want to spend the money on something you won't use very often, have a mechanic shop put on a mechanical gauge and verify your pressure. That is the only reason to put on a mechanical gauge. If the gauge shows that your pressure is fine, then you need to replace your oil pressure sender. If the gauge shows that your oil pressure is too low or too high, then you start looking at the other possibilities.

Some people do run a mechanical gauge as their sole oil pressure gauge. But that means you have engine oil coming into the cabin via a tube which could break (especially in the event of an accident) and possibly spilling hot engine oil into the cabin. If you go this route, most also have back lighting for when you need your lights and are connected via a relay from your headlight circuit.

 

[asutherland]

Do what John suggested and just have a shop check the pressure. They hook up a very accurate mechanical gauge and will tell you. It shouldn't cost much at all for them to do this check.

Then, live with the oem gauge, and know that it's actually fine. Just use it to tell if something drastically changes... like if the pressure drops to nothing, for example.