well i needed a water pump and the parts store only had the long shaft in stock. coming home of course i had the short shaft one. but when i bought me house there was an 1984 ford e350 rv left behind. so i checked the pulley and it fit the new pump. this pulley was smaller and i used the fan off it too this fan deffinetly is moving more air. and it all fit no problem what few problems i had are gone anybody know how this setup would effect operation. so far everything is workin great.