HJ47 2H Water Pump Pulley eating fan belts?

[robertbruce]

My HJ47 2H Water Pump Pulley is eating fan belts, i think. WP bearing & shaft no movement. Fan Flange no warp. Pulley definetly has a slight warp in it.
Can this be a spacer issue behind the flange? Or could new washers / seratted nuts fix this? Or does the pulley just warp anyway? What else can i check to stop the belts stretching? Wrong pulley on crank, WP, generator?

 

[jp147]

I can't really tell in the picture but is there rust or pitting on the pulley surface where the belt touches it?

 

[robertbruce]

not so much on the outer surfaces but... the pulley has close together double wall in the pressing which allows crap to accumlate then partially collaspe which deterioate the spin... i got another pully, no warp but 3mm movement laterall spin... also cleaned the rubber dust and gave all pulleys a good scrub with grrits... and a proper tightening... definetlty not tight enough on first attempts, allways been a bit shy on tightening fan belts and am surprised how hard to do these up... the 90 degeee twist method...has beenn working well