Originally Posted by tabetha

It's a load of bollocks about the belt not being retensioned, pure crap just to sell more belts, they "stretch a bit"!!!!!!!!!!!!!!!!!!!!!
They have a set PITCH and it they stretch the PITCH will alter, you would not then need a new belt then, but a new ENGINE INSTEAD.
It is perfectly fine to retension the belts, just keep the direction of travel the same.
There is a washer which is a GUIDE WASHER to keep belt in correct position at the crank pulley, it is CURVED, if some complete pratt has fitted this the wromg way it will chop your belt like this, the ONLY other bit to go anywhere near the sides of the belt is the tensioner wheel edges which are flanged so they act as a guide, but are parralell to the belt, unless the edge has been distorted and bent in.
Take off bottom pulley and see what's up, new belt as well needed, but perfectly safe to retension belt as they are not clarevoyant and do not know if they have been tensioned before or not.
tabetha