fitted the u/d pulley and had lots of belt squeal - even tightening them resulted in a squeal from the alternator belt when revved hard.

 

Spray WD40 on pulley/belt - shut em right up.

Not had the squeal since - Im thinking there must be a grease or something on the pulley, so if your getting squeal it may be worth spraying with wd40 before you get under car wielding spanners.

fitted the u/d pulley and had lots of belt squeal - even tightening them resulted in a squeal from the alternator belt when revved hard.

 

Spray WD40 on pulley/belt - shut em right up.

Not had the squeal since - Im thinking there must be a grease or something on the pulley, so if your getting squeal it may be worth spraying with wd40 before you get under car wielding spanners.

 

They shouldnt squeal bud when tightened correctly. You havent got one of those from ebay have you?

nope - got em from ZCentre - pucker unorthodox pulley and belts - got the wrong size pas belt but that wasnt the one squealing.