Water Pump Pulley

backwoodsboy · Mar 28, 2013

Anyone know if the water pump pulley from a Superduty will work on an OBS as well?
Ford lists the diameter of an OBS pulley at 6.68" and SD at 6.10". Any other differences anyone can think of...offset, etc?
Insight on whether a .5" reduction in diameter will throw my belt tension out of whack?

old man dave · Mar 29, 2013

backwoodsboy said:
Anyone know if the water pump pulley from a Superduty will work on an OBS as well?
Ford lists the diameter of an OBS pulley at 6.68" and SD at 6.10". Any other differences anyone can think of...offset, etc?
Insight on whether a .5" reduction in diameter will throw my belt tension out of whack?

Are you doing this to increase water pump speed?

backwoodsboy · Mar 29, 2013

Nope, not at all.
My pulley decided to explode....never seen anything like it to be honest. I'll post pictures when I get a chance.
Local Napa has a 99-03 pulley in stock for $60, FoMoCo has one as well at $70 and the quickest I can get a 95-97 pulley is next Thursday from FoMoCo to the tune of $85.

backwoodsboy · Mar 30, 2013

Anyone? I'm supposed to be delivering 12 cord of wood tomorrow, and hauling a connex Sunday, so input would be appreciated.
If not, I guess I'll throw the SD pulley on and see what happens.

rusty1161 · Mar 30, 2013

The SD pulley will fit. Same water pump and others running a Fluidampr run them to gain clearance to swap out serpentine belts. I have one ready to install

Rusty

backwoodsboy · Mar 31, 2013

Thanks Rusty.
Did you need to go to a shorter belt, or no?
Spent damn near an hour today looking through my Napa parts book for a 8 rib belt thats 0.25" shorter than stock. I'm probably just over-thinking things.

superduty4x4 · Apr 1, 2013

I have a water pump pulley from an OBS you can have for the cost of shipping.

backwoodsboy · Apr 1, 2013

superduty4x4 said:
I have a water pump pulley from an OBS you can have for the cost of shipping.

Thanks for the offer man, wish I had seen this earlier.
Got the truck patched up today using a SD pulley.

For future reference, the SD pulley worked fine but there was belt chirp at idle with the Motorcraft belt.
Motorcraft belt is 119.47" inside diameter.
I found a Goodyear Gatorback belt part # 4081190 that was 119" inside diameter. Half inch shorter was able to make up for the smaller diameter of the SD pulley...no more chirping.
Hopefully this helps someone out in the future.