Belt size

[hotratz]

Does anyone know the fan belt dimentions for a Herc. IXB3? Or the Napa part number. This is for my OC-46 alternator conversion. I want to use the original pulley and belt but don't have an old belt to go by.

[clueless]

Well, FWIW, a 1950 Gates catalog lists one line for IXB3:
"Herc IXB3...(Fan)...37 5/8 belt...OE 29836-A...Gates 758T..."
For their 758T it shows: length 37 5/8 OD, top width 25/32, angle 44 degrees.
A later Dayco skips the IXB3 (!) and a 69-70 Gates Vintage only lists Herc OE numbers, but the OE number above still shows a 758T.
 Hope that's what you're looking for.

[hotratz]

That's helpful thanks, Zimmerman says they use a Goodyear 24403 which they say is a 3/4 inch wide and 40 3/8" long. I'm picking up one from Napa that is 3/4" X 40 5/8" Seems thats quite a discrepancy from the one you listed. If that doesn't work the next size down from Napa is 37 something.

[clueless]

I believe the belt Gates listed is just to run the fan, not to run a fan and generator or fan and alternator, assuming it's a one-belt system. I'd assumed you understood these catalogs list some "fan" and some "fan and gen" when generators were an option; I should'v'e made that clearer.
   I was under the impression what you needed was the top width and angle to fit the original engine pulleys.
   Presumably Zimmermans belt (and he's the expert) is for the fan and alternator installation.
   I'm really surprised NAPA belts drop from 40 down to 37...did you mean that was the next one down with your exact top width and angle?? Belts should be available in numerous  fractions in between, altho not in your exact specs.
   Parts catalogs are often incomplete, and, like anything else, contain errors, which are sometimes from engine spec changes after specs acquired by the parts supplier, or spec changes after catalog published.
   Hope Z's belt is what you need.  Good luck.