starter/generator belt size

Super 12 mod.91725120 with craftsman engine 143652062(second 6 could be 0) ser.6190e(9 could be an . Starter belt missing. I know it's 3/8 in. but don't know length. Help?

Hi, Try the formulas that are shown here.

Steve

The belt length of various V-Belts and Synchronous Belts on a 2 pulley drive may be estimated using the formula below.

Belt Length = 2C + 1.57(D + d) +
(D - d)2
4C




C = Shaft Center Distance

For "L" series belts

Belt Length = Belt Outside Diameter
D = O.D. of Larger Pulley
d = O.D. of Smaller Pulley
For A,B,C series belts

Belt Length = Datum Length
D = Datum Diameter of Larger Pulley
d = Datum Diameter of Smaller Pulley
For Syncronous belts

Belt Length = Pitch Length
D = Pitch Diameter of Larger Sprocket
d = Pitch Diameter of Smaller Sprocket

go to sears parts put in your tractor model number find belt part number in your case # 3754H , come back to this site look-up sears number in the belt size section your belt is a 3/8 x 33 . sears has few parts left for these old mowers but they do have excellent information that can be used at after market part sites and ebay . sometimes just entering a part number in the search will turn up something .