Oil pressure/spraying help please...

[jimmy21669]

Ok, so here is the scenario:

I start my XJ and it immediately goes to 75 PSI oil pressure. I get on the highway and the needle pegs at 80 PSI. When I get off the hwy and come to a stop, I am now at 38-40 PSI, and never achieve higher than 50 PSI again.

Meanwhile, oil will be spraying out from somewhere on the passenger side of the engine. It get's all over my ignition wires, oil filter, etc. It is enough to be problematic. I cannot tell where it is coming from.

I have done all of the flush and fills. I removed/cleaned the valve cover and breathers and reinstalled with new gasket. I replaced the oil filter adapter o-ring...

SOMEONE HELP ME PLEASE!!

p.s. 91 XJ Sport 2 DR with 4.0 HO, 179,XXX miles.

 

[ParadiseXJ]

3 leak possibilities coming from where you describe.

1. Oil filter adapter - I know you said you replaced that but you mjay want to take another look.
2. Oil pressure sender - common leak, may explain the weird OP readings. Sender may also be shaky.
3. Oil filter mating surface may not match.

A leak with enough pressure to "spray all over" can be a tiny leak with lots of pressure behind it. There isn't much (if any) pressure under the valve cover, unless it's just flowing out from the valve cover and being blown around by the fan.

If it were me, I'd clean the engine bay up real good. Fire it up and see where oil is coming from

 

[wesley80us]

That is the same thing that I would give it a good cleaning and use some stuff called gunk engine degreaser and watch where the oil is coming from and then you will know where to start

 

[kastein]

I'd put money on the oil pressure sender. Explains all the issues at once; very easy to break while replacing the oil filter. Did you bring your jeep to a quick lube garage or bash into that sender while changing the filter?

You also could have left the old oil filter gasket stuck to the OFA and ended up with two stacked gaskets. Wouldn't explain the wacky sending unit issues at the same time as the leak though.

 

[jimmy21669]

I removed the old gasket. Could the oil pump have a bad oil pressure relief valve??

I can replace the ender...that is no problem, but I seem to ACTUALLY be having high pressure since I am getting spray....and it may actually be coming out of the dipstick.

 

[ParadiseXJ]

Even with low pressure you'd get "spray". Try running it with the sender off sometime and you'll see how much oil can come out of that tiny hole in a big hurry. Alot!! Real fast.

Oil pump relief valve might cause the strange readings but not the leak. Start with the simple stuff first. If you want to ease your mind about the pump and the pressure, put a mechanical gauge on it. The difference between 50 psi and 70 psi is not that much. I vote sender.

 

[drifto77]

I vote for the sender being your problem also.

 

[jimmy21669]

Is it possible that the oil pressure relief valve went bad, causing the sender to spring a leak? I have high pressure at first....then as it builds up I start to lose pressure due to the leak?

Could it be both?

 

[midnight]

I am absolutely positive it is the oil pressure sending unit. I had this EXACT problem. It finally blew the end off of the sensor and started to dump massive amounts of oil.

 

[jimmy21669]

So Midnight, in your case...when you started the Jeep it was reading 80 PSI until it ran a while then lost pressure?

 

[ParadiseXJ]

Is it possible that the oil pressure relief valve went bad, causing the sender to spring a leak? I have high pressure at first....then as it builds up I start to lose pressure due to the leak?

Could it be both?

If you think it's the oil pump, drop the pan and check it out. Replace it even.

I am absolutely positive it is the oil pressure sending unit. I had this EXACT problem. It finally blew the end off of the sensor and started to dump massive amounts of oil.

...or just change the sender. Which is probably why it's a.) pegging out and b.) leaking and c.) finally sending lower pressure numbers.

Then when it's leaking like a sieve and the oil is all warmed up, you can't get pressure over 50 psi.

 

[joe_peters]

You are going to get two different oil pressure readings--engine cold = higher psi; engine warmed up = lower psi.

That is NORMAL.

Now, concentrate on the leak. As said above, clean up the mess and then OBSERVE the area. Repair the source of the leak.

Once the leak has been repaired, you may find yourself without any further issues.

 

[kastein]

Sender's cheap/easy and it almost certainly has a problem. I don't know why you seem to want it to be a tougher repair

If you put a mechanical gauge on it (which you probably should do to find out if it's actually a pressure issue) and the leak stops, it's clearly the sender since that's the only thing you removed.

If it's not that, degrease everything, start it up, figure out where it's actually coming from. I'd bet that it is pissing out of the gauge sender somewhere, but if not, probably the distributor gasket.

 

[midnight]

So Midnight, in your case...when you started the Jeep it was reading 80 PSI until it ran a while then lost pressure?

Yep, my probelm was EXACTLY the same. Replaced the sensor in 10 minutes. Problem solved. AutoZone has one for $34.99

 

[jimmy21669]

Sender's cheap/easy and it almost certainly has a problem. I don't know why you seem to want it to be a tougher repair

I am not trying to make it tougher. I am trying to understand HOW the sender can give you a HIGH pressure situation that will cause an oil spray.

It is the combination of things I am trying to understand.

Could not the same thing be said about this hypothetical:

"My oil pump pressure relief is stuck and blowing oil out of my dipstick"?

Point is, if the sensor itself is bad, it will read 0 or 80, open or closed. It is actually changing pressure, so the sender itself may be good.

I am not sying it is not leaking from there, but what, in an engine, CAUSES high pressure. To me, that would be the oil pump pressure relief.

I will buy both, change the sensor first, then move on if that does not fix it. But I want to be prepared for both.

I also want to mention the pattern of oil spray. It is spraying onto the top of my ignition wires, but not the underside of my hood. This pattern would not happen if it was coming from the sender OR the distributor.

I will let you know how it works out there...so place your bets and I will announce the winner later :roflmao::roflmao::roflmao:

 

[kastein]

ah, I can understand that.

I've seen senders half-break in such a way that moving the housing moved the wiper, BTW. Fixed a friend's jeep that had that happen, some half-assed mechanic had broken the sender partway around where the metal end is crimped onto the plastic body and had simply daubed it with RTV instead of fixing it properly.

That's a really strange pattern it's being sprayed on, I agree... I'm not sure how that would happen.

 

[midnight]

I am not trying to make it tougher. I am trying to understand HOW the sender can give you a HIGH pressure situation that will cause an oil spray.

It is the combination of things I am trying to understand.

Could not the same thing be said about this hypothetical:

"My oil pump pressure relief is stuck and blowing oil out of my dipstick"?

Point is, if the sensor itself is bad, it will read 0 or 80, open or closed. It is actually changing pressure, so the sender itself may be good.

I am not sying it is not leaking from there, but what, in an engine, CAUSES high pressure. To me, that would be the oil pump pressure relief.

I will buy both, change the sensor first, then move on if that does not fix it. But I want to be prepared for both.

I also want to mention the pattern of oil spray. It is spraying onto the top of my ignition wires, but not the underside of my hood. This pattern would not happen if it was coming from the sender OR the distributor.

I will let you know how it works out there...so place your bets and I will announce the winner later :roflmao::roflmao::roflmao:

:eeks1: I know this sounds crazy, but mine was spraying oil the same way. that is why it took me so long to figure it out(until it broke) Like kastein said. They can "half-break" causing some weird shizzle to happen.

 

[jimmy21669]

I'm on it...I'll let ya'll know.

 

[jimmy21669]

I will be replacing the sending unit tonite.

 

[HenryKrinkle]

I think your valve cover could be leaking, causing the spray. Check that out while you're in there. Gotta torque those to 55 IN/LBS and if the gasket you used was cork, it'll compress so you have to do it again a few days after the first time. Nothing wrong with cork gaskets here, they just need to be retorqued.
I also think your pressure sender is off. Mine originally displayed a very high reading, then it went off the charts high, and back and forth. I got all worried about the pressure, then was told it is just a faulty reading. I'm pretty sure they're about 20 at autozone.