[72c20customcamper]

Originally Posted by Mike_The_Grad

I have a 72 c10 with a 350, non a/c. The alternator was mounted to the drivers side exhaust manifold, power steering pump was mounted on the drivers side down low. It has a short water pump with a 2 groove water pump pulley. The harmonic balancer is 8" in diameter and has a 3 groove crankshaft pulley. The power steering pump pulley is a single groove pulley.

I say that the alternator WAS mounted to the driverside exhaust manifold because I installed a set of " Standard-Duty" Hedman Headers. And the original factory mounting bracket no longer works because of the headers design. I installed an aftermarket Header Mounted Alternator Support Bracket with upper alternator tensioner arm that uses the top bolt on the drivers side of the water pump.

Now, the power steering pump bracket on small block equipped 72 1/2 ton trucks are of the "Non-Adjustable" type. Of course you can adjust belt tension, but that's about it. Because the pump is sandwiched between the front and rear brackets you are really limited in the amount of shimming you can do to align the pumps pulley with the others. BUT, there are different offsets of power steering pump pulleys out there. And I'll give you some advice that will save you a lot of wasted time and frustration.

IF YOU PLAN ON KEEPING THE STOCK SETUP AS IT CAME FROM THE FACTORY, THAT IS: NOT ADDING COMPONENTS OR SUBSTITUTING NON FACTORY ACCESSORIES.

Then you MUST use the correct pulleys and brackets that came equipped for your trucks setup. The power steering pump pulley for '72 1/2 ton Non/AC, small block v8"s is the only pulley that will work with the factory setups. TRUST ME. It took me 2 years to figure it out. I bought who knows how many pulleys, NONE of them worked except for the pulley that had the same exact part number stamped into it as my original did. Which was an original GM power steering pump pulley. These pulleys were only used on 71-72 small block, non/AC, 1/2 tons and blazers. THATS IT.
No other GM applications on any other model year vehicles.

The alternator is mounted on the passenger side if you are running a long water pump, drivers side if short water pump. THERE ARE DIFFERENCES IN THE OFFSET OF THE PULLEY GROOVES BETWEEN THESE TWO SETUPS.
Powersteering pump belt aligns with the outermost crankshaft groove on a 3 groove crankshaft pulley and short water pump. Alternator belt aligns with the middle groove on 3 groove crankshaft pulleys and long water pump setups. Or A/C compressor pulley aligns with the middle groove in this setup. Alternator belt lines up with inner groove of 3 groove crankshaft pulley and short waterpump setups.

This info only applies to FACTORY setups with FACTORY ACCESSORIES.

Thanks for the info but my truck is a 3/4 ton does it make a difference ? In regards to the pulleys.