In hopes of finding a double water pump pully, Im going to start with the balancer. I have a NOS balancer (C3TE-63TE-6316-E 3/8" double groove) that is listed for a 63-64 Ford Truck that had the option of a 2 belt generator. I swapped this balancer for the stock single belt dampner on my 56 F-250 272.
I found a double groove alternator that appears to have the same pully groove pattern as the balancer (approximately 5/8" center to center).
I am looking for a donar water pump pully that will match up or be close enough I can shim it. I have found several used three groove pullys but I do not want to use a three groove if I can find a two groove that will work.
The water pump pully I need is approximately 6 5/16" in diameter. Cant be larger or it will interfere with the generator/alternator bracket sold by John Mummert. The fan belt will rub in the bracket. The hub diameter of the water pump is 2 5/16" The shaft diameter of the water pump is 3/4". The mounting hole pattern is 4 hole and approximately 1 1/4" center to center on all four holes.
When I lay the pully face down and place a straight edge across the back, a tape should read a minimum of 2 9/16". If its more, I can shim it.
Im still searching wrecking yards and have inquiries on line about after market options, but nothing yet. It seems like if there was a double pully dampner option for a 63-64 truck, there should be a double pump water pully out there that would be the same belt groove pattern and offset that would bolt up.