Lube oil leakage near of the transmission - PeachParts Mercedes-Benz Forum

nyko46 · #1 03-27-2009, 01:14 PM

My 1982 300SD with 244Kmiles has for a long time an oil leakage from underneath of engine and it is becoming worst every day.
After wash the engine very well from top to botton with engine degreaser and water with a pressure washer machine, I found the first drips of oil coming around the place where engine and transmission are connected.
I had my transmission rebuilt in September of 2008 but the leaking was there before that job been performed.
I was wondering if there are any chance of the oil leakage coming from oil seal at the rear end of the crankshaft if there are some seal.
In case of worn out seal what should be done to repair or replace it?
The transmission must be removed?
Your idea is welcome.
Thanks
Nyko46

daddi · #2 03-27-2009, 06:42 PM

I just fixed this problem in a M110 motor the main bearings on your crankshaft are getting worn to the point that the rear seal cant hold any more. Rip the engine out as soon as possible and replace the bearings before there is more very expensive damage.

pselaphid · #3 03-27-2009, 06:48 PM

Check oil filter housing to engine gasket before you remove the engine

nyko46 · #4 03-27-2009, 07:04 PM

Couple times just after washing the engine I kept an eye at that area but not oil leak found there. Some another idea?
Thanks for your help.

nyko46 · #5 03-27-2009, 07:09 PM

Could you tell me where is this bearing located and how much work will be needed to replace it?
I allways do myself repairs on my MB but sometimes I am limited by some special tools if required.
Thanks for your help

tangofox007 · #6 03-27-2009, 07:09 PM

Quote:

Originally Posted by nyko46

I was wondering if there are any chance of the oil leakage coming from oil seal at the rear end of the crankshaft if there are some seal.

Chances are that the leak is something other than the rear seal. I know one MB mechanic who says that he has not seen a rear seal leak on a MB diesel in 30 years. Replacing the entire rear seal requires removal of the crankshaft; it's a rope-type seal.

I would suggest investigating the oil filter housing gasket, the valve cover gasket and the turbo oil supply line that crosses behind the engine.

nyko46 · #7 03-27-2009, 08:27 PM

I had never thought about the turbo oil line.
I had checked the oil filter housing, valve cover gasket and there are not leaks but I never heard about turbo oil line.
More exactly, looking underneath of the engine I can see oil near where transmission and engine are connected. Does turbo oil line cross near that area?
I will continue to check for new areas.
Thanks for your help

tangofox007 · #8 03-27-2009, 08:33 PM

Quote:

Originally Posted by nyko46

More exactly, looking underneath of the engine I can see oil near where transmission and engine are connected. Does turbo oil line cross near that area?

The line runs from the rear of the oil filter housing and behind the rear of the head. There is a bracket that can wear through the line and cause an oil leak.

nyko46 · #9 03-27-2009, 08:59 PM

Quote:

Originally Posted by tangofox007

The line runs from the rear of the oil filter housing and behind the rear of the head. There is a bracket that can wear through the line and cause an oil leak.

I just check that area after reading your post but there are not one sign of leak. The top of the engine is 100% clean of any oil leak. The only spot where I can see oil is where I told before.
Thank you again.

nyko46 · #10 03-31-2009, 08:12 PM

Quote:

Originally Posted by daddi

I just fixed this problem in a M110 motor the main bearings on your crankshaft are getting worn to the point that the rear seal cant hold any more. Rip the engine out as soon as possible and replace the bearings before there is more very expensive damage.

Hi:
I have read your and many other posts about this issue and most of those posts talk only about the Rear Engine Crankshaft Seal. They also say that this seal is a rope seal that split in two pieces. Before go further and remove engine of the car which will be a head ache to me because I don't have engine hoist to put out the engine, I would like to know how hard or difficult will be to do this job with engine in place. Also I would like to know if there will be necessary to separate transmission from engine.
Your help will be really appreciated.
Thanks.

barry123400 · #11 03-31-2009, 10:37 PM

Unfortunatly the engine has to be removed to even get the oil pan off. Separation of the transmission is also required. First though get a mirror on a stick and critically look down the back of the engine. Just to absolutly eliminate a flow path down the back of the block. It should be bone dry and clean above the bellhousing.

You want to be absolutly sure you have a rear seal leak before pulling that engine. It could also be a failed oil pan gasket as a possibility. Clean and check until absolutly or as positive as possible as to where the oil leak is before going on. The rear seal involves quite a bit of effort to get to.

nyko46 · #12 04-02-2009, 04:37 PM

This leak is an old leak but it became extremely worst after a trip of 700 miles and now I can see oil dripping from that area. Yesterday I drove to work and just after park the car I was looking under the engine and suddenly a loud knock start with the engine in idle. I shut it off immediately and after three minutes I start the car again and the noise came back but only in idle. I push the accelerator softly just to increase the RPM to about 1300 RPM and the knock stopped but came back when in idle. As my trip between work to home is about 10 miles I did not drove the car back home to investigate a little more about this loud noise in idle and get ideas from other fellows that know better than me about Mercedes engines.
As an engine removal and replacement of main bearings and rear seal was suggested in this forum, just to compare if it will be a better and less expensive deal than have my engine removed and rebuilt, I decided to call a place in CA where used complete and tested Mercedes diesel engines are sold with exchange for $1500.00
I had not yet checked how much will cost me removal and installation of the engine not matter if replacing or fixing.
I would like to hear what people of this forum think about it.
Thanks

winmutt · #13 04-02-2009, 05:18 PM

1500 is a lot for a used engine. $800 is much more reasonable, without a core. Another 6-1200 to install. Can be done in 3 days with a hoist.

It's not red oil?

JonL · #14 04-02-2009, 05:22 PM

That knocking noise... did you check your oil level? Did you have oil pressure on the gauge at idle? Don't drive the car like that--not even a little.

As far as the rear seal leaking... if you can see the front side of the flywheel (the side away from the transmission) look for a characteristic pattern of rays coming from the center of the flywheel. This would indicated oil leaking from the main seal onto the flywheel and being flung outwards by centrifugal force. If that front surface of the flywheel has no evidence of oil like this, the leak is likely elsewhere.

nyko46 · #15 04-02-2009, 05:28 PM

Quote:

Originally Posted by winmutt

1500 is a lot for a used engine. $800 is much more reasonable, without a core. Another 6-1200 to install. Can be done in 3 days with a hoist.

It's not red oil?

It is not a red oil but a lube oil.
Where a good engine can e found for $800.00?
If you have any place that you can recommend please let me know.
Thanks