Fan idler pulley alternatives?

[vintagespeed]

I'm running a York on a homemade bracket where my a/c pump & battery used to be, it's an '89 4.0L. The serp. belt will fit fine & the pulley is already machined for it but I need a slightly smaller diameter idler fan pulley. I know this will spin the fan slightly faster, but I dont think it'll detonate. Any ideas? :thumbup:

 

[RCP Phx]

An "idler" pulley will not change any of your main pulley speeds!

 

[2xtreme]

I do not see how it would affect the speed either. I would guess it would be easier to get a slightly longer belt instead of a smaller pulley, but assuming that is impossible I would probably just make one on the lathe with the stock bearing size or go totally custom and use a new bearing also.

Michael

 

[RCP Phx]

I would guess it would be easier to get a slightly longer belt.

Michael

"Oh,Please",equipment speed(rpm's) is based on the FPS(feet per second) speed of the belt and the "driven" pulley.The equipment speed is based on the diameter of the individual pulley's.

 

[vintagespeed]

The idler I have is right below the thermostat housing. I need the smaller pulley to let the belt clear the housing. I have the big cast iron thermo housing and I could take some material off it but the pulley seemed like the better idea. I was smoking crack earlier and was thinking that the mech. fan was mounting to it, but when I sobered up I realized it mounts to the water pump. My bad, my bad.