Hi all >From all the failed balancers I have seen...which have not been that many, as far as TOTAL failures go...first the outer ring slips on the inner, and then if its left unattended, the outer ring comes loose from the inner. You have to realize, these are two metal rings with a ring of rubber between them ( simplified view here ) and they are pressed together in such a way that it takes MANY years before they would come loose. I suggest taking a paint pen, or just a brush and some easy to see paint, clean a small area on the face balancer and put a stripe across the rings...if it starts to slip, youll see that. Another clue, your timing marks wont even be close to the pointer anymore...thats a very easy to see clue also, all you need is a timing light. If you ever see one thats going, or gone...youll never forget it. Btw...keeping excess oil off the things is good, as oil has a tendancy to attack a lot of rubber products. Youve all seen what oil soaked lower radiator hoses do, they get very soft and mushy. OK...thats about all I wanted to know on balancers! :) Take care everyone Mikey 62 Crown Coupe