Over the weekend I replaced the alternator bracket seal and the driver's side upper timing cover gasket, along with solenoid o-rings. During the job I cleaned the engine real well in order to detect any further leaks. Well, after starting the car and running it for a while, I found a leak that seems to be coming from the lower right hand water pump bolt. I carefully tightened the bolt and that helped slow the leak, but didn't eliminate it. At first I thought it just needed a new water pump seal, but after thinking about it, if the seal was bad it would be leaking coolant, not oil. The pump bolts onto the lower timing cover, so apparently the bolt hole goes all the way through the timing cover, and oil is coming from the timing chain oil supply.

Has anybody run into this before? It puzzles me, because it seems like the hole there should be a blind hole, not all the way through the cover. Maybe a manufacturing error?

Next weekend I'll take off the water pump and see what's going on. Hopefully some RTV will take care of it.

 

Hey i have the same problem, i took it to BMW and they didn't even know where the leak came from.

 

picture of where this leak is?

 

I dont think the water pump bolts penetrate to any oil passage. I am guessing the oil is coming from someplace else or maybe the cover is cracked. If the bolt was suseptible to oil seepage, BMW would have used a sealing washer or specified thread sealant. None of which is true in the TIS or ETK.