It gets worse...new oil pressure problem-1990 cherokee 4.0 L str.6cyl

well its not doing it now that its cool.

I wonder what that means.

she took a quick trip to the grocery store just now, before I get started.

hopefully its the sending unit.

if its the screen clogged I ll still have to take everything apart to clean it I guess,

The oil pressure sending unit is mounted next to the oil filter.

If you’re going to replace the sending unit, make sure it’s one for a gauge and not one for an idiot light.

Tester

k

The oil pressure sender is next to the oil filter. I would also recommend replacing it and hoping for the best. If you remove the wiring harness connector and find any evidence of oil leaking out at the connector it is likely that the sender is failing.

yeah, engine pretty oily, hard to tell if sending unit leaking yet. I have computer outside and am jacking it up and putting on stands under shadetree now. I have to do brakes for sure so I m gonna get wheels off and hope son comes by too.

the thing is running ok and not getting hot so maybe ill get lucky

jacking up the front of jeep with 3 in lift is a pain :slight_smile:

I would check oil pressure at hot idle with a mechanical gauge.

thank you all for the advice. it makes a big difference for our family.

I will check on that @circuitsmith.

question… does the fact that I had zero, but not below the line, oil pressure today, after long, hot ride, when stopped in drive, and that when I put it in neutral and the idle increased slightly it went back up to 20…

…and that later, after it cooled down, it did not drop to zero when stopped in drive, indicate any thing to you?

it was the first time that happened, I pay attention to my gauges

and the work I did yesterday with ccv vacuum tubes and getting them functioning again, and the fact that the pressure and idle seemed to work much better after…
…would that cause anything else to fail?

I wouldn’t think that this pressure guage is accurate at all. If you had -0- oil pressure you would have been frying the motor. You didn’t mention that every thing started to knock and bang???

I’d get a new mechanical guage. This one must be bad and I’d want to be sure of my oil pressure after having so many problems with it.
A new one may indicate that you have much better pressure than you think.

Yosemite

yeah Yosemite, I tend to agree, but it only had no pressure showing at idle for a minute at a couple stop lights and I shifted to neutral and it went up. I m hoping it the sending unit tho.

but now I have a huge problem with brakes and maybe rightside front drive parts

first the brakes. should be no prob. said remove caliper bolts with allen key. only prob is thay they are not allen key. I cant see anyway to get any wrench on them, they don’t seem to have a head at all, just a couple tiny ridges around them. maybe a cap I have to remove??? I am flummoxed

and they say replace if caliper bolts are stretched or brakes will drag. well the one side seems stretched, caliper is a little loose, and it seems to drag on that side.
but I can t figure out how to remove the darn bolts, hey have nothing to grab!!

and on that side behind the wheel and hub there is a universal of some kind and behind that there is a plastic cap that I think covers some kind of bearing which isloose and making a clack clack noise as the wheel turns. I thought it was my brakes but I guess its more serious

I m not very happy right now. I wish I was in colorado
thanks
wes

I have never worked on a cherokee so i’m only guessing.
ARe you sure that the allen or torx head is not filled full of road dirt and grease.
I’ve had many that have a rubber boot like seal that the socket has to pass thru to reach the hex head. They are usually a tight fit too, so it would be hard to see the hex head.

There’s a u-joint at each wheel end of the front axles and another at the opposite end where they attach to the front differential.
Those…lke any u joint can get dried out and fail. That could be the noise that you hear.

Hope this helps

Yosemite

no I think its after the u joint behind that plastic cover, but I could be wrong

and there definitely not a hole filled with gunk

but there is a rubber boot!!! it was pretty tight but I pulled it back a little and saw nothing, the end of the bolt goes thru the boot tho, it would be a strange kind of bolt

thanks ! at least ill go to sleep with a little hope1

I have no doubt that my book may be wrong about the hex head, it sucks,or some one could have put newer calipers on, my

I think my ald ranger had those boots and a 10 MM socket did fit in the boot, but it was tighter than a …well I’lll just stop there. But they were really tight.

Try forcing a few different sockets into that boot. I’ll bet you find a bolt head deep in there.

I just thought, they couldn’t be those pins that you drive out. ARe they accesable from the front of the caliper.

Yosemite

no, I have that type on my old ford truck

my first four wheel drive. I can t believe I can t figure out how to get the #$#$@! caliper off

I just checked NAPA and Advanced to get a picture of what you’re dealing with.

You’re right, they just look like a bolt head.
I have nothing to offer then…sorry!!!

Yosemite

The pins you were looking at were for a 2 wheel drive with an internal hex hole. You need the ones with an external, 12 point bolt.https://www.rockauto.com/catalog/moreinfo.php?pk=542017&cc=1179996

mine is supposed to be allen keys, later just shows bolt head. maybe its in the boot like you said.

they do have some VERY small ridges , that might be it old timer

where on gods green earth would I get a tool to remove those