i have recently had a new water pump fitted, but when i put the cam belt back on and start it up it seems fine, but when the cam belt covers get put back on it seems to be rubbing on the cover. You need a special tool to adjust the tension wheel but i used 2 small allen keys, which seem to work fine, i have done this several times but the belt just seems to work its way loose and the tension wheel seems to move. can anybody tell me where i am going wrong??????