I just replaced the oil pan gasket on a B230 engine. There was a leak at the rear of the engine and it had been dripping for a long time. It was a pretty dirty job!

Has anyone experienced other leakage points on the rear of the engine besides the oil pan, distributor seals, and rear main crank seal? The front of the engine is dry and leak free.

What is the typical replacement interval on the green distributor o-rings, and how often should the dynamic seals in the rotor plate be replaced?

I know about keeping the breather clean. It gets removed and cleaned at every oil change.
--
D '90 745T 229k, '88 744GLE 129k, '96 328i, '73 911T 100k+

You might also want to check the oil breather box seal. These tend to bake real hard over a period of time and you can get a slow weep/leak onto the back of the block which might drip down to the back of the engine. Usually not a big leak, more of a weep. O ring only costs about $1 to replace, although removal of the breather box might take an hour or so. A poor seal here also reduces the effectiveness of the breather system which can cause leaks elsewhere to get worse. If this is a turbo, the seals under the oil filter adaptor also tend to get hard and leak. Again, a couple of $$s for the parts and an hour or so of labor.
Distributor seals may start to leak anytime from 75k miles upward in my experience.
Good luck,

Kevin
--
Current: '95 945, 98k miles; '90 BMW 325i, 95k miles. Former Volvos, gone but not forgotten '85 245, 250k miles; '91 744T, 150k miles

I'll try the distributor o-rings first as I know they haven't been changed since I've worked on the car, and then the breather box seals if I've still got leakage. Hopefully it's NOT the rear main.

Thx.