There are 3 or more sizes. 2 3/4 up to 3 3/4.
I understand for the larger sizes you have to pull the pan. My belt will not stay on the original fitting, so I was thinking a pulley would be in order.
Any suggestions on why one size is better than the other? Experience with a certain size? Ease of changing the pulley?
Thank you for your assistance.
Crank pulley sizes were basically matched to fan pulley sizes. The early smaller crank pulley was used with the smaller diameter cast brass and cast steel fan pulleys. The larger crank pulley was used on the later cars with the larger diameter aluminum fan pulley.
Putting a large diameter crank pulley with a small diameter fan pulley will get the fan spinning pretty fast!
In addition to the difference in the fan pulley, the crankcase design was changed for the larger diameter pulley to provide some added clearance.
I have a large pulley on the crank and small one on the fan. Not only does it spin fast like Ron says, you have a hard time finding a belt for it. In fact, I'm using an idler pulley to make it work. I've got the shortest belt I can buy from the local auto parts store and have to use the idler to make it work. Stick with the correct combination and I'm pretty sure you can buy a belt to fit.
I should have added a sentence to my post... If you stick with the correct combination, you can buy a belt from a T parts supplier that will fit.
Dave,Have you used a straght edge to check pully alingment?? Are you using a quality belt?? Bud.
The car runs fine without the fan belt, but it heats up fast when standing still and that is why I would like a working belt. It is a 1924 speedster with a dizzy.
If the pulley is too large, the belt will probably rub on the dizzy, so I was thinking a smaller pulley would be better. I also read that the smaller pulley can be installed without having to pull the pan - am I right in that?
The belt is tight, and Royce said that might be part of the problem. It should be a loose fit??? I do not think it is exactly aligned, but is a bit off, and the belt is just the common brown belt sold by the vendors.
I have found that things are often not square such as fan brackets also pully alingment,and a pump can also throw things off? I use only Gates Belts and i have seen the cheap belts not made right not all but some are junk.If the belt is too tight it can pull things out of alingment.Bud.
Snyder's sell a split aluminum pully which can be installed with the pan in place. Makes lining things up easy and the belt doesn't work off. I have tried several of them.
Can you please look it up and let me know which pulley you are talking about. Thank you.
Page 44 of Snyder's catalog,Item #T-3963-RE,$59.95ea.
If you're using the correct period crank pulley for your pan, you should not have a clearance problem that requires pulling the pan.