I had a closer look at the seat for that steel ball, and this I saw:



is this normal? From below left that canal goes up and partly 'eats' into the seat. Can I still put in that steel ball and give it a firm tap to seat it?

email (option): viaconsu # planet dot nl

Your photo looks like the crankcase directly beneath timing cover?

If your photo is actually of the timing cover, find another cover.

email (option): n.gentner@bigpond.com

Arrrggghhh, serious senior moment , this hole is indeed in the crank case, and there is no spring+ball inside, sorry

email (option): viaconsu [at] planet [dot] nl