oil cooler lines

[Larry Larson]

Howdy,
I have a slight leak where the oil lines go into the oil cooler on my 300TD. I know this is a common problem. I've heard they can go suddenly causing a sudden catestrophic loss of oil. Others say they can leak like this indefinately are not a cause for concern. Any thoughts? Thanks. Larry

[samiam4]

IF you have any signs of leakage- replace the lines.

They are not expensive- just very messy to install. You can probably have them installed (p&L) for $350 or so. I'd buy dealer parts on this one... I've heard problems with aftermarket fit and quality.


Michael

[luckys420]

change them!!!! i too had a small leak. then on a trip i stopped to get something and noticed that my tire was really shiny, then i noticed that the side of my car was no longer beige it was black. I had no loss of pressure or anything and infact, it did not leak to much at idle. But at free way speeds it must have been spitting out. i changed my own, wrecks some pants, and a t-shirt but otherwise it went smoothly.
will

My oil cooler lines are weeping oil too. I suppose it's time to replace them... they're beginning to make a mess.

[Larry Larson]

Thanks folks,
I'll take care of it pronto! Larry

[WANT '71 280SEL]

I think I am in Lucky's situation now. When I was on a trip to get our 420SEL we stopped at a rest stop in Ohio. I noticed oil was running out of the holes in my bundt rims! I looked underneath and the springs, calipers, EVERYTHING was covered in oil. Now my car pulls to the right becasue I think the oil damaged the left front caliper. I cleaned evrything off, even the rim, with carb cleaner and no more has been building up there since I replaced my oil pan that had a crack. The oil is leaking so bad though that i don't know whaich line it is or if it is the oil cooler itself.
Thanks
David

P.S.
When the oil was on the rim, it was delvac synthetic. I have switched back to 10-40 since it's getting wamrer and it still leaks although not to the point of covering the suspension parts, etc.

[Jetmugg]

I just changed both oil cooler lines on my '80 300SD this weekend. It's a pretty significant job. You need to be mentally ready to get dirty. I pulled the oil filter housing off the block and replaced those 2 gaskets as well. I removed the driver's side engine mount, which was probably the toughest part of the job. Some say it's not necessary to remove the engine mount, but I don't think I could have done the job with the motor mount in place. I tried and couldn't. I did the whole job with the front end of the car up on jackstands, and it took about 4 hours total, including about an hour of fussing and cussing before I decided that it was necessary to remove the motor mount. The rest of the work is just plain grimy and slimy. This is one of those jobs that you "Only want to do once". Do it right the first time. I'll let you know if mine will stay leak free.

SteveM.

[samiam4]

I think the manual says to remove the motor mount bolt.


I've done it that way and you can put a jack on the engine and raise it a bit for extra clearance. Good to have a thin wrench for the line connection on the oil filter housing- I used an old 944/928 belt adjustment wrench. Put a bunch of cardboard under the car- there is no way to get it out without making some mess. I think mine took me about 2 hrs, but I was very fast that day-and lucky!


Michael

[Jetmugg]

I ended up removing the entire mount - from the block and from the frame. I didn't even consider just removing the allen head bolt from through the frame and then jacking the engine up. If that will allow enough clearance, it's a great idea. The four nuts holding the mount to the block are some tough mothers to get off.

Steve.

[kerry]

I understood the question to be, not whether to replace the lines because the lines were leaking but what to do about a leak at the fitting to the oil filter housing.
I don't see why it is necessary to replace the whole line if the leak is at the fitting. The fitting on my 77 300d has a slow leak at the fitting which I have not gotten around to fixing yet. But when I do, I will fix the fitting itself and not replace the whole line unless there is evidence the line has a problem. It is highly unlikely that a leak at the fitting will suddenly turn into a catasrophic failure.

[Larry Larson]

Thanks for all the help. I took my car to my mechanic today and scheduled a time to replace both the lines. He's a certified independent MB diesel specialist and he said they don't tend to fail catastrophically. Since I'm taking this car on a trip to California in a few weeks I wanted it taken care of anywat for the sake of my peace of mind. Larry

[WANT '71 280SEL]

Update. my brother took my car to our local independent MB mechainc to have the idler bushigs replaced and then have it aligned. I still don't see how people get the idler bushings out, I've tried everything. Anyways, he saw a puddle in the bottom channel of the oil cooler and said my cooler is actually leaking, not the lines becasue it was only wet at the bottom and not at the top where the top line mounts. Is it very normal for an oil cooler to leak like that?
Thanks
David

[luckys420]

double check yourself, clean it all up real nice, and then turn the car on and watch.
Kedwards, I thought that it was the fitting as well, then i cleaned it all off and noticed that it was comming out of the area where the rubber is attached to the metal. it was dripping down the metal lie and around the fitting and apperard to be leaking from the fitting only.
lc