M50 engine oil leak

scotsman60 · 02-20-2007, 03:51 AM

Hello,

I have an M50 motor that is leaking engine oil from the front of the motor. The origin of the leak is behind the crank damper (?) - where the crankshaft nose holding the damper and ribbed belt pulley comes through the case/oil pan.

Mt Bentley manual doesn't have much detail in this area. If I remove the pulley, damper and oil pan is there a replaceable seal in this area? Does anyone have a detail diagram of this area or expereience of working in this area?

TIA,

Doug

Yurick · 02-20-2007, 04:58 AM

It sounds like the source of your leak is the front main seal (crank shaft seal). It is not too terribly to change out, however, you may need to remove the radiator to make room to work.

scotsman60 · 02-22-2007, 07:50 AM

Yurick,

Thanx for the info. What kind of seal is the front main seal? I can't see it on RealOem.com or in my Bentley manual.

Do I have to drop the oil pan or does it just press in after I disassemble the pulleys and stuff?

Thanx,

Doug

Yurick · 02-22-2007, 10:33 AM

Doug,
It is your front crank shaft seal.

Jeron · Jeron's Garage

#4 here I think
http://www.realoem.com/bmw/showparts.do?model=CB33&mospid=47498&btnr=11_0157&hg=11&fg=10

scotsman60 · 02-22-2007, 02:48 PM

Yurick, Jeron,

Thanx - I was looking at the block and not the timing case cover....

Looks like I just need to dig out the old seal - carefully, not scratching the bore, and then tap the new one in with a suitable cylindrical drift such as a large socket.

I'll give it a try this weekend. Hopefully this will fix the problem.

Doug