Thanks for the link Chad--very cool of you to provide. I will contact them tomorrow.

Doug

Doug --

The STEWART pumps have a set screw to add some additional security to the fan hub... and their hubs are billet (on the stage 3 stuff) instead of a machined casting. Either way - I'd make sure you have the big shaft version (3/4" vs 5/8")... or you might get the big shaft again! LOL

You can check your pulley alignment using a straight edge against the pulleys.

Oh... you have that SMALL small block.. :>) -- Actually - I'm thinking of de-stroking mine when I rebuild it. Those little bitty pistons (in mine) just aren't good for a high milage motor.. :willy:

Found this on the Stewart website... Very interesting.



When using a mechanical fan, a properly designed shroud must be used. Most mechanical fans are not designed for high RPM use: they can have serious vibrations problems, due to air turbulence, when run over 6,500 RPM. This is a turbulence problem, not a balance problem, and will destroy the water pump and components in front of it. The large fans preferred by dirt oval track racers can consume up to 18 horsepower at 6,500 RPM. Do NOT run a mechanical fan that is any larger than required for the application.

Flex fans are a poor design for performance applications. They move less air at higher RPM, and only consume a fraction less power than standard fixed pitch fans.

Clutch-style fans are inconsistent and we do not recommend their use for any application, if possible.

Sorry to hear Doug... hey it could have been worse and at least you were close to home.

Yep,pulley alignment is critical, ask me how I know. The first go around on the Camaro I swapped the six for a junk yard 350. I went thru 2 napa water pumps, pulling the entire pressed in piece thru the front both times. The NAPA dude was super cool and returned them. When I went back in for the replacement after the second one failed he pulled me to the side and told me to check the pulley alignment. I fixed the alignment and the pump lasted about 8 years until the entire motor was jerked and the new and improved car was built.

Darren

Great stuff there Greg. I will ditch the clutch fan---I am literally just buying time until the other motor goes into the car. It's then that I will clean up the engine compartment to my liking and get rid of many things--that should happen in this coming year---I say "should"---depends on what else comes flying off the car before then. Thanks again man.

Doug

Ok Darren, I am on it and will check it----I am suspicious of the A/C belt being the culprit---

Doug

yeah, in my bare feet, no phone and kids at house----there goes that "Parent of the Year" award I was looking to get.

Doug

Driving with no shoes! I like it! :lol:

Doug- I had the same problem a few years back. My problem started when I installed a "Heavy duty/towing" fan clutch. It took too long to disengage and would overspeed the fan. The fan vibration would rock the flange back and forth until it moved on the shaft. Luckily the belt was thrown before the fan fell off the pump shaft. I went back to the standard clutch instead of the heavy duty one and it solved my problem. I thought heavy duty meant that it could withstand more rpms. It is really designed to just move more air. May not solve your problem, but thought I would share...