Replacing Turbo Oil Drain Seals / Gaskets - Help - PeachParts Mercedes-Benz Forum

#1 09-04-2003, 01:49 PM

I've got an oil leak and I'm not sure of the source so I thought I'd do some low-cost things like replace the oil pan gasket and the turbo oil drain seals / gaskets.

Once I remove the skid plate, how do I locate the turbo drain and what's the best approach?

dmorrison · #2 09-04-2003, 02:48 PM

Edited for One question???
Skid plate?? This is a 81 300TD correct? 123 did not have skid plates. Or do you have a different car or a modification to the car???

You have an oil leak. I would suggest spraying the entire engine with gunk engine cleaner. Let it soak for 30 mins and then use a high pressure washer to clean the engine as much as possible.
Now drive it for a day and see if you can figure out were the leak is.

OK so you want to replace the oil pan gasket and turbo oil output Orings.

It is an easy job.
Jack up the car and place it on jack stands. Strong and high jack stands for the easiest acess to the oil pan and turbo Orings.

Drain the oil and you might as well replace the oil filter.

Unbolt all the allen bolts that hold on the oil pan. Make sure to keep them in order. Some are different, longer, which you will see.

Clean the pan and engine base completely, no metal tools, you don't want to gouge the metal surfaces.

While you have the pan off, check for metal in the pan and then completely clean it.

I found it best to have the pan off while R+R the turbo oil tube Oring.

To R+R the Oring unbolt the tube that is attached to the turbo. the upper tube slips over the lower tube and the Oring is at the top of the lower tube. The lower tube goes into the top section of the oil pan and has a gasket that should be replaced.

To remove both tubes you unbolt the top as said, and rotate ( by this I mean push perpendicular to the oil tube at the center joint, where the two tubes meet) the upper and lower tube so that they will separate at the middle joint. IF your lower turbo tube oil pan gasket, item #95, is original and hard. You may have to dig it out of the upper oil pan with a screwdriver, small of course, to get it to release. Mine was hard so I had to do this. Be careful not to gouge the metal so that you don't create another oil leak.

Parts of the lower tube gasket may fall into the oil pan, that is why I liked dong this job with the oil pan off the car.

Install the new lower gasket ( #95), both Orings(#93) and the new upper gasket (#90). Do this by fitting in the lower gasket. Insert the lower tube, with the new Oring, into the gasket and then the new upper Oring. Slide the upper tube down onto the lower tube and bolt the upper tube to the turbo with a new upper gasket.

To ease the instalation of the Orings and gaskets you can use engine oil on the parts to allow them to assemble easier.

Install the oil pan gasket and bolt the oil pan onto the engine. Torque the bolts evenly and DO NOT OVER TORQUE or you will warp the oil pan. Install the new oil and filter.

Dave

#3 09-04-2003, 03:42 PM

I'm not sure what you meant about editing?

I certainly do have a skid plate on my '81 300td. It has a "hole" in it for access to the oil drain plug but otherwise covers most of the bottom of the engine.

I know that I should be taking the time to spray down the engine and look for the leak, I fully plan on doing it, but figured I might as well start with the most logical (and simple) things first.

dmorrison · #4 09-04-2003, 03:57 PM

Edited just means That I added the question after I posted my reply.

Skid plates, they are aftermarket. They were never offered by Mercedes on the US 123.

This job will take about 3-4 hours IF you have all the tools and have everything ready.

Degreasing and spraying is a 30-45min job.

Dave

PS If they are Mercedes skid plate, Called encapsulating panels, the 126 300SDL has them. What is the Mercedes part number on them. I wouldn't mind have a set for my 82 300TD.

jbaj007 · #5 09-04-2003, 04:37 PM

MB skid plate part# 123 520 03 42 for a 1981 300TD.(and it appears to be a skidplate, not the S. E. panel)

Sound encapsulation panel (which is what he is most likely referring to) part#...don't know.

cuban8 · #6 09-05-2003, 06:09 PM

I've had a skidplate on my 126 for years. MB part, get it at the dealer, a few hundred bucks, weighs about 30# (no, it is not aftermarket). Wouldn't be without it.

I understand they were very popular in South Africa (other 3rd world locals too). Almost unheard of in the USA.

dmorrison · #7 09-05-2003, 07:30 PM

cuban8

126's came with an encapsulating panel. My 126 has 2. One for the engine and one for the transmission. But I have no such thing or have I ever seen such a thing for the 123.

jbaj007

part# 123 520 03 42 this was only for the 81 wagon?? Were they made for the 82-85 series?
What does it look like, How much of the bottom of the engine does it protect?

Thanks

Dave

cuban8 · #8 09-05-2003, 09:16 PM

I don't believe my 126 (1983 300SD) came with sound panels. I purchased the skid plate (perhaps it should be called a "rock guard") about 10 years ago. Special order from the dealer.

It bolts on the front crossmember under the radiator then extends rearward and bolts onto the crossmember directly under the engine. Protects everything in the engine compartment forward of this crossmember under the engine. Has rubber "snubbers" in the right places to prevent rattle. Very heavy duty and well designed.

I think it was a dealer installed option many places outside the USA.

-Regards

#9 09-24-2003, 06:15 PM

I read dmorrison contribution describing change of oil pan gasket and turbo drain seals. It sounded doable. However, I m stymied at the point of separating the two parts of the return line.

Before that, getting the bolts that hold the upper part of return tube was a true challenge. Can't reach them from underneath and can't see them from above. Did finally get them out but it was quite tough.

Now, I just can't separate the two parts of the return tube. There's not enough room to pull the upper part off while the lower is still in place, and the lower cannot be pushed up high enough to come out of the oil pan. I have rotated the upper part every which way and can get it to where I can feel the o rings on the lower tube, but there's about 1/16" less room than I need to get them apart. That is there's still a bit of the lower tube still in the upper tube, and they just won't quite separate. In the back of my mind also is wht it's going to take to get them reassembled since assembly is usually harder than disassembly.

I would hate to take the turbo off to finish the job. Is there another way?

dmorrison · #10 09-24-2003, 08:10 PM

NEVREM

This happened to me also.
I called and talked to a Mercedes Tech. He asked how old the lower rubber bushing ( item # 95 )was. I told him it was original. At this time I think 17 years old.
He told me that the lower rubber seal had hardened and that I had to dig it out with a small screwdriver ( actually It broke apart in pieces) to get it to allow the lower tube to rotate towards the horizontal some more, to allow the 2 tubes to release. I needed that 1/16 inch more movement, as you do. Digging out the lower rubber bushing will allow this movement. I did this and they came out. REMEMBER I had the oil pan off. So any rubber debris that fell, did not go in the oil pan.
Once the tubes are out the new rubber is quite soft and you can install the lower Orings and rubber "gasket". Because they are softer the tube will rotate towards the horizotal sufficently to allow the tubes to mate.

Dave

leathermang · #11 09-24-2003, 09:00 PM

Be sure not to put ANY water on the injection pump when you wash it unless it is stone cold... it can not be warm and shot with water of any temp without taking a chance on really messing it up...tolerances are tooooo close....

James L · #12 07-20-2007, 08:48 PM

Help! On my 1984 300SD, I can not get the upper tube in, there is not enough room! I spent 4 hours trying every angle and rotation, even removed the air cleaner and tried to go in from top, no room. been reading searches on this forum, fsm and Stu Ritter/Richard Easely diy.

Do I need to remove the wastegate/turbo? Do I need to shave 1/2" off of upper tube "bell area"? I got the bottom tube in with new oil pan seal/orings installed and tube bottoming out in the oil pan. oil pan is removed.

What a @#$&^ PIA this job is as warned and expected!

Any tricks/ suggestions?

300SD83 · #13 07-21-2007, 12:15 PM

This link helped alot: http://articles.mbz.org/engine/diesel/seals/

JHZR2 · #14 07-21-2007, 02:04 PM

its a tough job... not tough in any one part of the job, but getting everything together with the two-piece drain going into place properly is a real challenge.

It just takes time. Put on some good music and dont have a need to go anywhere, else itll really stress you out.

did mine twice on my 83 300D, and there was still a leak. Cleaning the flange on the turbo is a real tough job because there is little precious space, especially if your hands are large... I think when it was done previously, it must have been gouged, because I could never get it to feel really smooth...

Be careful with that!

JMH

Jeremy5848 · #15 07-21-2007, 05:15 PM

I put a skid plate on my '85 W123 last year -- see this thread for the DIY I wrote:

W123 Skid Plate Install w/pix

I bought mine from Phil, about $125, I think. It is made of heavy steel and attaches at 4 points. It should protect the oil pan from being bashed in by rocks and other things that stick up. It's primarily sold to people who drive in "semi-off-road" conditions. It's not an "encapsulation" panel -- my '87 has those so I understand the difference.

I bought it because I lost the transmission in a non-MB car to a big rock in the road (thought it was a paper bag) and didn't want to lose an oil pan in a similar situation.

Jeremy