UK Car Repair: Fan Belt, car designation, opel vectra b


Question
I have a 1996 Opel vectra B 16,1.6 (Same as the vauxhall in UK).My problem is that my mechanic does not recall the original fan belt size.He  currently uses 6pkk 1800 which often snaps without warnin. Can you please help me out with the right fan belt size for my car?

Answer
I have no access to data on modern European vehicles unless they are sold here in the USA. BUT, if the belt is breaking it means it is the wrong size.  The mechanic should be able to tell by feeling the tension and movement on the belt. If too short the tensioner will not compress it enough, if too long, it will have too much slack. Why can't you just order the correct belt by the car designation?