Re: Clutch Fan on Packard V8

Posted by BigKev On 2007/7/17 21:34:49

**Original Post from JoeH moved to correct thread**

HotRod,
I used an OEM, single sheave pulley and mount flange from an early style SBC water pump. I think the change in water pumps was in late 1960s or early 70s, and it definitely requires the early style.

Basically, press the Packard flange off the water pump shaft and then press the GM one on. Because the GM pulley is shallower, the flange must be seated further down onto the WP shaft in order for the pulley to line up with the crank and generator pulleys. When aligned, there is less than .050" clearance between the WP mount bolts and the backside of the pulley.

The 21.5" fan came off a late 60s to early 70s BBC, fit the clutch perfectly, and has clearance room in the 1956GH. Generally, the engine compartment is much more crowded in a GH, so I am thinking this mod would be even easier in a Packard.

The fan is smoother, quieter, and thanks to the modern temp sensor on the face of the clutch, the clutch friction adjusts according to air temp coming thru the radiator. With the smaller diameter pulley, the water pump is sped up, and circulate the water faster, which is helpful at low RPMS.

I love the setup, just need time to convert the other one someday.

Joe H