1992 LJ73 2.4L TD Oil leak issue (14 Viewers)

[TheSquare]

Hey!
I recently bought this vehicle and it's running well and in overall good shape as far as I can tell.
Some time within the last couple of weeks it started leaking oil however. Still investigating where from exactly.
It does seem to be coming from somewhere around where the dipstick goes next to where the turbo connects to the engine. Then seeps down from there and coats everything on the way... It drips from the bottom of the sump, where the gearbox mates with the engine, and several other spots. Which leads me to believe it's coming from the top and getting splattered around. Mainly the left side of the engine seems to be coated in fresh oil. But I'll be cleaning the crust off with brake clean so I can more clearly see what's what.

Cursory googling suggests I might be dealing with bad gaskets or seals (and I'd like to avoid tearing down the engine if there are easier things to check first), or some excessive gas pressure in the engine which causes the dipstick tube to spurt out oil. But my experience with this engine dates back only a few weeks and I haven't worked with turbo-charged engines before either, so I can't say what part that might play in this.

Maybe the car was already leaking when I bought it and it's gotten worse since then to the point I only noticed it now. There have been no noticeable differences in the behaviour of the car over the last 7-800km though, but that might not be enough to be able to tell. For now I will keep driving it and keep a close eye on the oil level and pressure gauge. Right now I don't know how much oil it's actually leaking, only that is does so only when running. But without doing a couple of oil changes I can't know for sure how bad it is. Main thing is that it doesn't lead to a bigger issue down the line, and I guess it shouldn't as long as there's still enough oil?

Surely this is just the beginning of finding all the lovely secrets of this car. I'm in love with it though, and more than willing to put the time and money into keeping it in good shape. Out of the faults I know of, this is the only one that is potentially critical so far. Any resources or suggestions on how to diagnose/fix an issue like this?

 

[Rigster]

Sounds like you are on the right track of cleaning things up first so you can actually see what's what.

Until then, I would suggest to start with checking the oil feed and return lines from the turbo. Is the dipstick leaking where it goes into the motor? Check around the oil cooler as well, anywhere the oil travels and it's connections. If you have not already, download the service manuals from the resource so you know what to look for.

Once the block is cleaned up, you will be able to see if it is a valve cover gasket, or, hopefully not, a head gasket. Is oil coming out of the bell housing? Then you would be looking at a rear engine seal, which is more common than a head gasket to leak.

Best of luck finding this gremlin and hopefully it is not too arduous to mitigate!

 

[TheSquare]

Yo, thanks for the advice!
Do you have a link to those resources? If anything, googling it gives me too many results and not sure what to look at.

The leak around the dip stick seems to be from the top of the tube as opposed to where it connects to the block. There is oil gathering on the bell housing, but I'm hoping that's because the oil ends up running there because it's a low point it can drip from.

Extensive tear downs are not in the cards atm. I've got very limited space to work on it. But I'll be setting something up at the in-laws cabin next year. It seems that would be wise, given this leak

 

[AirheadNut]

Look under the "Resources" tab here on Mud or check the manuals thread at the top of the Diesel forum here. There should be 2L-T and 2L-TE manuals there.

 

[TheSquare]

Today I took a look at some of the possible points of failure. And found both good, bad and ugly.

Good thing is that the dipstick tube doesn't seem to be shooting oil due to overpressure in the engine. Though there still seems to be a leak somewhere close. Which we'll get to...

The bad stuff is that the turbo does seem to be leaking on both sides of the engine. I cleaned up the lines under it on the right side but I'm still looking for the exact locations of the leaks on both sides. But the lines running from the bottom of the turbo seems a likely culprit.

Part of the challenge here is that the leak on the right side runs down and drips on all sorts of areas. One being the front axle cv joint. Which then enthusiastically centrifuges the oil all over the bottom of the engine... I'm going to clean things up tomorrow and see if that gives me a better look at what's happening there.

 

[TheSquare]

So. On the topic of spinning cv joints throwing oil everywhere. Enter, the ugly zone. The t-case rear axle seal seems to be leaking...

Part of me is looking forward to the man I'll be once I've sorted this particular mess out. Oh and the left side turbo? This oil feed line (or return line, still working my way through the manuals) was missing a clamp. It wasn't necessarily coated in oil, I still think there might be adifferent leak around there somewhere. But this gave be a bit of a chuckle.

The plot thickens, I feel like I'm just shy of finding the leaks on the engine. The drain rate isn't very concerning so far either. Oil level hasn't visibly changed in the last 100~ km. The transfer case leak is a bit more of a mystery to me. I never had to touch it on my old subaru. So there's some reading ahead of me there to figure out how to check oil levels or refill it. At least I presume it isn't getting oil from the engine? Would it still be ok to drive with a leak like that? Mind, I haven't cleaned the underbelly for the last 800km, but it's hard for me to judge if it's a concerning amount of oil getting carouseled around...

Either way, the drive line and underside of the engine will get cleaned tomorrow as well so I can monitor it going forward.

 

[AirheadNut]

Excellent progress on finding the leaks. On something as old as this it is common for all sorts of things to be weeping a bit of oil. The turbo oil feed and drain could certainly be leaky, as could the turbo itself. Try taking the intake boot off the turbo and checking the turbine shaft for play, both radial and axial. There should be some radial play but not enough to allow the turbine blades to contact the housing, and very little axial play. Is there oil in the crossover pipe going to the intake manifold?

Judging by the extent of the gear oil flung from your transfer case output I would highly recommend checking and topping off the transfer case fluid. The fill plug is on the rear of the case near the PTO, fill until fluid comes back out the hole. Likely the leak there is due to a failed rear output shaft seal, luckily that is replaceable without removing the transfer case from the vehicle. Once the seal is replaced you'll want to do a fluid change on the transfer, and it probably would be a good idea to do the transmission as well if you don't know when it was last done.