Oil leak from behind timing cover

[h0wz3r]

Hi guys

just been out for a ride and noticed a bit of oil seeping out from behind the plastic timing cover, mainly on the bottom hex bolt.

I haven't looked any further yet but it's only a small amount, residue even.

Is this anything to worry about or look for? I've cleaned it up for now to see if I can work out where it's coming from. I'll post a couple of pictures later so you can see what I mean.

From the outside I can't see much corrosion if at all but I'm at a loss as to where it could be coming from?

 

[RickG]

if it's from behind the plastic cover (the one that covers over the alternator belt and not the metal timing cover behind it) then it's either the crankshaft oil seal or an O ring sealing the small square cover over the balance shaft bearing. Either way, if you take the plastic cover off, which is a10 min job, you'll probably find the source

 

[h0wz3r]

I've had a good butchers behind the timing cover now and nothing was immediately apparent. It looked generally gunked up so I cleaned it all down and then ran the engine for a few minutes.

After much inspection and head scratching, I could just make out a tiny drop of oil starting to seep out from behind the big wheel at the bottom. It's not much but it did look fresh and therefore that's where the leak is coming from.

Is this the crankshaft seal then? If so, how big a job is it to replace? I'm no DIY man so it would be a garage job whatever it is.

At the same time I removed the foam insert at the front as it was so gooed up with general rubbish that when I tried to wash it it just started to disintegrate!

The bike is booked in at Rainbows BMW for the problem to be investigated so I might tell them what the problem is now and get a better idea of cost.

 

[RickG]

The big wheel thingie is on the crankshaft so yes, seems like the crankshaft oil seal has gone.

In principle it's an easy job: take off big wheel thingie, remove the oil seal by screwing an extractor into the walls of the seal and pulling, push in new seal. However, if the seal removal doesn't work as expected then the timing cover will have to come off so the seal can be driven out from the inside and the job gets much bigger and takes longer, but is still not that difficult.