Genny belt length

I need to replace the genny belt. The "new" 12v genny, along with the new brackets I have, don't allow for much adjustment room. Plus I have to keep this genny tucked in close to clear the hood. Using the pictures below, [b:fc4b99dffd]how much off [/b:fc4b99dffd]would you say I need to take from the replacement belt? Meaning: If my current belt is 24" (I really have no idea how to correctly measure them, I'm just using a random number), would you say I should take off 4" and order a 20" belt? Or, how do I measure to determine what I need?


As you can see below, there is very little room to adjust the tension of the belt, so I need to get it right. This picture is taken with the genny fully pushed into the engine. All that adjustment space to the right in the picture cannot be used.






With the genny fully pushed in, I can pull this much slack out of the belt:






With the genny fully pulled out to the stop I can pull this much slack out of the belt:





So what do you think? How much shorter should I get the new belt? How are belts measured? Should I be asking for anything special? (I plan on getting it from Napa)

Sorry for the long post and all the questions, but you know me... I ask before I screw something up!

Thanks

First off, is that an adjustable sheave gen. pulley?
If it is, you could go an inch less length on the belt. Belts are measured around the outside circumference. You can measure your belt length by using a thin tape measure & run it around both pulleys leaving the belt in the grooves. Stretch the tape tight & read the measurement.
Back to belts--Gates makes gen. size belts in 1/2 inch increments--so I'd imagine that other suppliers have them also.
Now for belt length--looks like I'd get a 1 inch shorter belt than you have now, & it should be close.

Mike, read you manual. Look at the illustrations. The top bracket for the generator is not supposed to be slotted. The generator is mounted in a "fixed" position, and the belt adjustment is done with the adjustable sheave pulley. A standard H generator belt is what you need.

Mike on your post down below your bracket that your genny is bolted to is turned down. I beleive if you turn it up you can use a longer belt. Bob

I think that tractor had an alternator when Mike bought it, so yes, the bottom bracket most likely has been turned upside down, and needs to be turned right side up again for the generator to fit properly.

If I flip the lower bracket upside down the generator seems to hang out way to far. I'll do it, and show a picture so you can see.