And here I am again, feeling I have exhausted all of my solo efforts to solve my new problem I come to everyone here. I have an oil leak on my 97 Disco, WHHHHHHAAAAAAATTTTTTTTT? I know right. But here's the thing, I just completed an oil pump replacement, main and crank bearings replacement, replaced oil cooler lines, timing chain and gears and an oil change. Multiple oil changes because of the work i did really.

I have a leak of oil that is dripping off my passenger side (USA) motor mount. It looks to be blowing back underneath the whole under carriage and getting oil on my cat causing a good deal of smoking and obvious worry. There is also oil dripping and pooling on top of the front diff/axle but no oil is getting on my exhasut manifold. That valve cover has been replaced already so its not that either. It is not the oil pain or timing chain gasket. I pulled the oil pan off again (3rd time in 3 weeks) and verified that. Pictures coming tonight.

 

While you are under the truck taking pics have a good look at the oil cooler lines. Look hard at both the steel part and the hose.

Also when you replaced the timing chain cover and removed the oil cooler lines, did you remember to replace the O Rings (with new ones) on the cooler lines?
Once you post a pic or 2 it should be clear were the leak is coming from. Good Luck!

 

I replaced the oil cooler lines and the o-rings are there top and bottom. I will give them a good twice-over though just in case...

 

The oil cooler lines have (5) O rings total. (2) at the radiator and (3) at the engine cover.
Have a look at the pics.

Also look at the oil pressure switch for a leak. That also has a washer and an O ring(#STC3372).
You can see it in the 2nd pic (behind the 1st red arrow).

 

All of the o-rings are there. The pressure sender is not leaking either. The crazy thing is that this should be an obvious leak with how much is coming out. It was raining today so no its not leaking water, Here's the pics:
There will be more oil in the morning hanging off that pumpkin and under it.
Here you can see the oil pooled on the diff.
This is the motor mount oil. It is also all over the starter, wires and starter heat shield.
The cat that was cleaned the night before with degreaser and steel wool. It went 30 miles then started smoking again because oil is splashing on it.
Top down you can see the oil on the cat, the oil also runs down the O2 sensor wire and burns on it.
The only reason why I don't think this is a valley gasket is because the oil is isolated to the rear of the engine.

 

No chance in doing the multiple oil changes that you have doubled up an oil filter ring? I’ve seen it happen to the best.

 

Without first cleaning engine up/down and carefully inspecting after each run you'll continue to chase your tail.
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I cleaned and leaked, cleaned and leaked. It almost has to be the oil lines I just don't know how. It has to be a pressure leak because it seems to only cause a problem when it is driven, Guess I am going to have to put the GOPRO under there during a drive and see what happens... And there is no doubled up oil filter gasket.

 

So I did just hooked up my gopro to the panhard bar. I drove a round trip of 25 miles or so to chop wood for a lady. When I reviewed the footage I was suprised (though in hindsight I shouldn't be) to find that it was the high pressure bypass valve cap leaking. I stared at that thing a number of times to make sure that it wasn't it but it turns out you need to rev the engine 2k plus to get the oil to come out. It then hits the oil filter and lines and blows back onto the passenger side of the motor. Confession time: I replaced that o-ring with what I had. Probably not the best choice I made during the past month of work on this hog. But hopefully this will fix it.

 

That was a great idea to monitor with your gopro. Now I can see the benefits of one in my future. Easy to justify the time to learn the OS and using it as a tool. Thanks.
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