[NoColoradoGT]

Hey guys. Okay. I need helping badly.

My '90 is leaking oil like crazy and burning through about 1 quart every 40 or so miles.

Also, I just did a nice cleaning job on the bay and now there is burnt oil splattered all over the left hand side of the block and the left hand side of the bay. I can get pictures later, I'm just at work right now. I'll try and snap some at lunch.

In any event. I know what all this stuff usually means but I need help figuring out which it is.

I know it could be either a bad valve, bad seals or a head gasket (please God, no. hahah) It's not throwing blue smoke that I can see (the lady has been driving it while i've been away the last three days and had to add three quarts of oil), however it started burning oil so bad last night that it was very lightly smoking from underneath the hood. I had to add two more last night and the dipstick is reading 'Full', however the pressure gauge is lower than 20 psi at all times and drops down to nearly zero at a light.

What in God's name is going on?

[03SonicBoom]

What Jeep?

The first thing I would do would be to clean up the engine bay, drive it a real short distance (or just turn the engine on), and find out where the oil is coming from.

As far as oil pressure, the first thing I would check is the oil pressure sending unit (on mine it's a $15 part). If that's good, things start to get worse quickly.

[zinc-vert02]

intake? head gasket? sounds stupid but maybe the oil filter is leaking onto the exhaust

[NoColoradoGT]

Sorry, 1990 Jeep Cherokee Laredo, 4.0, 150,026 miles.

I need to run a compression test for sure as well as check that unit, however since this thing has been an on going project, I had just inspected that unit not too long ago, but something may have happened since then.

The issue literally has developed over the course of 5 days, and I personally just witnessed it about 12 hours ago. My lady has been driving it and told me about the issue while I was in Vegas. Last night on the way home from Denver, it burned 2 full quarts of oil on the way home.

The Jeep had a very light, very slow oil leak early but it was nothing more than like a couple drips within a 12 hour or so period. Now it's a shit ton of oil, and like I said, shooting oil into the bay and burning oil. I can't keep the goddamn pressure above 20 psi.

[zinc-vert02]

maybe oil pan gasket or rear main leak

[03SonicBoom]

If it's shooting oil into the bay there probably is not an issue with the sending unit. It probably can't keep the pressure high enough because it's too big of a leak.

[NoColoradoGT]

Ugh. I can see this getting expensive fast.

and I JUST got done with about a 200 hour paint job on this SOB.





Give me about an hour and I'll get some shots of what's going on.

[zinc-vert02]

wow paint looks great

[NoColoradoGT]

Originally Posted by zinc-vert02 wow paint looks great

thanks man. If it's too expensive to repair I'm just gonna sell the thing. and I'm honestly not terribly concerned about losing the paint job. It was just 80 bucks worth of rustoleum primer, gloss black enamel, and clear coat, but it was a shit-ton of sanding and I just filled a bunch of holes in the body. I also just replaced the starter on the motor as well as a new air filter, fresh tranny flush, four BRAND NEW tires with less than 300 miles on them, two new U-Joints, about 50 hours of work to get everything on the 4x4 System going good again...and too much more to list.

To have this shit come up now just suuuuuucks.

[TheUNZippee!]

Do what Sonic said, get some Gunk, and wash that thing under the hood, then try and see if you can spot where the leak is coming from.

[HMUSN]

Clean it up good. Then pop the hood, start it, and go look. If it is leaking as bad as you say it should easy to see where it is coming from. You not getting blue smoke from the tail pipe is a good sign. The smoke under the hood is just from the oil hitting the exhaust. It is probably something simple honestly.

[sickfox]

Not sure how you mean left from inside or when looking at the engine. lol Had to many people say it wrong.

So ill name things to check.

Check the oil filter adapter, oil pressure sensor, and check the sending unit again. But just clean it like mentioned and look.

[sickfox]

pics?

[sonic04edge]

I wouldn't kick it to the curb just yet. A decent used motor isn't all that expensive for them if all else fails and you cant fix it.

[FordmanT]

Like they've said, probably the pressure sender, it is on the oil filter adapter housing and is always under pressure and will leak a ton of oil! Also they typically go from nothing or slow to a river. Start there

[NoColoradoGT]

Hey! You're from Loveland! Welcome!

Find me and a bunch of others on RaceNoCo.com as well!


Back to topic:

I haven't had time lately to run any tests and have just been DDing the Mustang again. However, I will get some tests done this week and post some videos for you guys. I'm reaaaally throwing around the idea of a new engine though. I found one at a local junkyard with 87k on the clock for $600, and I'm strongly considering just taking my happy ass and a credit card down there pretty soon. This Jeep only has 150,0XX miles, but it has been beat to shit. I have some service records of the vehicle showing more than 7,000 mile and 2 year oil change intervals. Also...the air filter hadn't been changed since 1998. I was the first person to wash it in three years before i sanded it down and painted it.

[FordmanT]

Sure am, born and raised! Cool maybe I'll check it out sometime. Anyway with your Jeep, the junk yard engine wouldn't be a bad idea but not really nessary, those 4.0L will go a long long time with a lot of abuse! Really, I would probably put money on the sender. I'm head tech at a Loveland shop if you ever really need some help.

[sickfox]

Yeah, if its not knocking or ticking dont replace it. Find the exact source of the leak before doing anything major.

I know guys with 200+/250+ still wheeling them and the abuse dont get much worse then that. (except thos oil changes)

[brokenweasel]

I had one of those with 214k on it that was a total POS. From what I read (and experienced) the rear main seal is a 2-piece and not very good. Thats where it leaked. HOWEVER, a bunch of the vacuum lines/Crank case ventilation stuff was missing/broken. So, I ripped off a bunch of the hoses and plugged the gaping holes on the valve cover. This caused the engine to build up lots of pressure and literally pour almost a steady stream out the rear main seal. Now, assuming yours is still in good, has compression and not too much blow-by, replace the PCV valve and see what happens? The problem with oil leaks in the engine is that the oil usually sprays all over the place so its hard to pinpoint.

[sickfox]

it had 214k and you say it had a bunch of broke and missing hoses. LMFAO Im gonna guess you didnt take care of it. Or someone didnt hahahaha no wonder it had problems and the low mile mark of 214k.