flathead alt conversion belt help
 

I'm having trouble finding a replacement belt for my 239 flatty. I found a replacement belt but I need one about 2" min. Where are you getting you belts? I have the real fat ones.

What do you mean, 2" shorter?

When you run wide belts, I think (not sure) you don't get any choice. Stock or nothing is my understanding. Could be wrong tho.

Not meaning to hijack here, but where does one find a wide groove pulley to fit an alternator? Just curious.

Believe it or not, the stock flathead generator pulley fits a GM alternator. But they are making wide pulleys just for the alternator conversion kits.

correct. on both accounts.

What I'm saying is my alt belt no longer fits the engine it's to small by a lot. I'll have to triple check how it's mounted again. Could the alt be upside down? I';ll check the folks who manufactured the bracket/ Lastly I just realized I may be able to cut down the bracket to give me more movement.

bob

I just went through this. Alternator on 8ba wide belt truck pumps. NAPA #'s 5L360 and 5L560. You can get belts in one inch increments from NAPA.
Pete

Good info Pete!

Bob, the alternator should be in the same location as the generator was, and with the same size pulley, I would expect the stock belt to work. Got a pic of the setup? I assume it's the slingshot style?

Pete thanks for the #'s

Ross, I'll post up later if I can. (honey-do projects) It is a slingshot style is that yours in the pick may I ask the dimensions of it ? at least the bottom section.

I'm starting to think I have the alt upside down? this pic was taken from the passengers side.

nope either way alt measure the same distance. does any one have a measurement on a factory belt? I may have an undersized belt on here. Maybe PO used a different bracket and belt??


36" and 56" listed on napa


The outside measurement of my alt belt is 54 1/4" That may be the issue...

you can use a fabric tape to get you number. run tape around all pulleys. as a wide belt should never bottom out on pulleys, don't pull tape tight. just snug in center of pulleys. if adjustment is at lowest point, add 1 inch to number and this should work.

The 36" is for the L6. Gates lists the stock belt length as 55.5" outside length, 55" effective length. The belt shown in my picture above is a 53.5", so the alt must mount a little lower. Not entirely sure if that is a wide belt or narrow, tho.

What kind of alternator is that?

delco 78amp it's marked "good" so it must be :)


it looks like I have a little more room but the bracket is bottoming out on the engine. As a last resort I could lop off the bottom of the bracket???

bob

Is it hitting the timing cover? Honestly, I'd just get a longer belt. If you mount the alt low, it may just mean you need to buy a shorter fan belt, and you go thru the whole mess again.