Fan Belt Routing

[Bill Stephens]

I have a 1969 350/300 w/o AC. The water pump has two pulleys, the crankshaft has three, and the alternator and P/S pump each have one. I think it is configured so that the P/S belt goes from the pump to the farthest forward crankshaft pulley, and the alternator belt goes from the alternator to the farthest rear pulley on the crankshaft and waterpump. I'm assuming that the middle pulley on the crankshaft and the farthest forward on the waterpump are for AC if the car had it.

Is that right? Everything seems to go together perfectly but the alternator belt rubs against the P/S pump. I could move the alternator so that it uses the forward pulley on the water pump but would have to rig up some kind of spacers on the alternator bracket and don't think that's right. I thought this would be a simple change-over from headers to stock manifolds, but it's about to drive me crazy. Thanks.

[Brandon Metzger]

Re: Fan Belt Routing

Bill,
Are your pulleys original? I ask because I just looked in my assembly manual for my '72. Shouldn't be much different than your '69. I believe your water pump pulley should have two grooves, the crank shapft pully should have two gooves. Your power steering belt should go from the water pump to the crank shaft and around the power steering pully. This belt goes on the outer groove. The inner groove has the belt going from the crank shaft pulley to the water pump pulley to the alt. pulley.

Your discription above is correct, however if the pulleys are not original or ment for your engine you could have spacing issues. Let use know what solves it.

Also, are your Alt. brackets correct? If not that could change the location of the Alt. just enough to cause your problem.

Regards,
Brandon

[Joe L.]

Re: Fan Belt Routing

Bill-----

I'm VERY familiar with your application having owned one for almost 35 years.

Your waterpump should have 2 pullies on it "sandwiched" together. The inner pulley is a 2 groove pulley. The outer pulley is a 1 groove pulley.

The crankshaft should have 2 "sandwiched" pullies, also. The inner pulley is a 2 groove pulley and the outer pulley is a 1 groove.

The power steering pump should have a 1 groove, stamped steel pulley.

The alternator pulley should be a 1 groove, stamped steel type pulley

Now for the belt routing:

1) Inner waterpump pulley groove and inner crankshaft pulley groove should hold a captive belt that routes between the 2 pullies only; there is NO adjustment on this belt; the exact correct length MUST be used;

2) Middle groove on both crankshaft and waterpump pullies and alternator pulley should have a belt, adjustable at the alternator;

3) Outer crankshaft pulley and p/s pump pulley should have a belt routed between them, adjustable at the power steering pump;

4) Outer waterpump pulley and AIR pump pulley should have belt routed between them, adjustable at the AIR pump. ALL 1969 Corvettes originally had AIR.