How do I remove this bearing?
 

Ok, this is on a '79 300 D.

I have a very bad oil leak at what was told to me as, where a "mechanical tachometer" would hook up to. Now I have never seen a mechanical tach on a 300 D, but maybe there is, I dont know. Located on the drivers side of the head next to the #1 cylinder and glow plug.

Anyway the oil leaks only while the engine is running. It bubbles up between the "bearing" and the head. Not where the large bolt and crush washer go. Looking down the hole and poking around with a screwdriver, the shaft is connected to something in the engine and will obviously not rotate with the engine off.

I had mentioned to a friend of mine who says there is an "O" ring on the outside of the bearing between the head that is causing the leak. But he does not know how to remove the bearing.

Question is: How the heck do you remove the bearing to replace the O ring? It sure does not lift out.

Maybe a special puller?

i could be
 

halucinating but i seem to remember that that plug covers a hole that is solely providing access to a bolt that holds something important in. cant remember what, but that is what it does, i think.

the mechanical tach story is very creative! your friend gets points for imagination, but not for integrity. one shouldnt say what one doesnt know for sure! unless they say that they dont know for sure...you know like i did. heh, heh.

tom w

Well I never have seen a 123 body with a mechanical tach for sure. I have seen several in the junk yard (non turbo) that have this plug. It just leaks a LOT of oil when running.

is it
 

leaking around the al crush washer? it looks pretty much like an oil plug to me. the al crush ring is the seal, it appears.

tom w

NOT the washer, I wish it was.

sorry
 

i am out of memory now. some one will chime in though, i am sure.

tom w

That looks like a tough one. I can't really see from the picture, but if there is some room in that bore below that bearing, you may be in luck. You can then fashion a little steel bar with a threaded hole in the middle, fish it through the ID of the bearing and pull it up with a long screw. -IF you have the room to do it below the bearing.

Bearing in block
 

Well, it is going to be rather involved to replace the oring on that bearing. I cannot remember where the securing bolt is located but behind the "Injection Pump" drive gear rings a bell. Give me some time to review some of my old material to see what I can come up with, I'll get back to you by the end of next week. :cool:

Anyone have any ideas???

Is that in the front of the engine? Could it be the chain tensioner assembly? they have a bolt on them too, I remember my 92 300sd had something like that on the front side of the engine. Could that be it? It would make sense that you had a lot of oil pressure there.
Brian

no
 

i believe it is on the other side and mounts horizontally.

tom w

The chain tensioner is on the passenger side. The mystery bolt is on the drivers side.