Resistor bypass and belt squeal **FIXED**

[Finnegan1008]

I will check into this. Are there any new solid steel pulleys that work? I have a source for core alternators but I don’t want to have to risk getting a bad pulley

 

[Finnegan1008]

So after checking all of my connections with out any obvious answers. I found a machined steel pulley that is within a few thousandths of being identical to the stamped steel unit. It's only $15 so I figured it was a cheap experiment.

After swapping it in and checking for precise pulley alignment (a thin shim from the hardware store puts this at the exact same alignment as the stock unit). I started it up and with both heat and headlamps running there is zero belt squeal even when cold.

Problem solved.

I will be swapping out the other alternator pulley for one of these units asap. Also I will take pics showing measurements between the stock pulley and this new one.

Also I want to mention the stock pulley wasn't badly bowed out, the 3/8 gates belt still sat within the groove seemingly OK. However there was a little wobble on the stock pulley.

 

[Sharecropper]

So after checking all of my connections with out any obvious answers. I found a machined steel pulley that is within a few thousandths of being identical to the stamped steel unit. It's only $15 so I figured it was a cheap experiment.

After swapping it in and checking for precise pulley alignment (a thin shim from the hardware store puts this at the exact same alignment as the stock unit). I started it up and with both heat and headlamps running there is zero belt squeal even when cold.

Problem solved.

I will be swapping out the other alternator pulley for one of these units asap. Also I will take pics showing measurements between the stock pulley and this new one.

Also I want to mention the stock pulley wasn't badly bowed out, the 3/8 gates belt still sat within the groove seemingly OK. However there was a little wobble on the stock pulley.

Thanks for your post and the information. However it would be helpful to post the source and part numbers for the pulley's and shims you used for those SS members who might want to duplicate your exercise. I don't need the info, as my pulleys are already aligned. But some of the junior members with squealing belts may want to fix their rigs. Just saying......

 

[Finnegan1008]

Thanks for your post and the information. However it would be helpful to post the source and part numbers for the pulley's and shims you used for those SS members who might want to duplicate your exercise. I don't need the info, as my pulleys are already aligned. But some of the junior members with squealing belts may want to fix their rigs. Just saying......

I will post all the details, I need to do a proper write up with pictures and will do so after work when I can do that properly. Stay tuned!

 

[Finnegan1008]

For those that are wondering this is the pulley I used

Alternator/Generator Pulley 3/8" (10mm) Belt Width X 2.933" OD X 17mm ID - The Brillman Company

#B9028-020, Alternator/Generator Pulley Used On Alternators & Generators With 17mm Shafts Belt Width: 3/8" (10mm) Outer Diameter: 2.933" (75mm) Inside Diameter: 17mm Does Not Have Keyway/ Accommodation for Key

brillman.com

One of the alternators that came with my truck was aftermarket and the (very important) factory alignment spacer that comes behind the fan was long gone. All of the CUCV parts sellers I know wanted $40+ for a crusty core alternator and couldn’t guarantee they had a fully OEM setup with a non damaged pulley. So I figured I would make this inexpensive option work.

as you can see from the hight difference photo the new pulley is about 70-75 thousandths thicker at the hub. This would set the pulley forward slightly on a stock alternator with the factory spacer. However on my aftermarket alternator a few inexpensive machine shims from True Value that I was able to ream to fit the alternator shaft did the trick to get the right spacing.

IF I had a bone stock alternator setup 15 mins of lathe work to shave about .075” from the hub could make this new pulley essentially identical to the OEM. If I didn’t have a lathe I would get some local machine shop to do it.

As you can see I don’t have the proper measuring device to measure these pulleys but this is pretty darn close.

I know this may make some of the purists cringe but I didn’t have the good fortune to get into these trucks when they were cheap and plentiful. I have zero parts hoard and need to be a bit creative once in a while.

 

[nyoffroad]

So after checking all of my connections with out any obvious answers. I found a machined steel pulley that is within a few thousandths of being identical to the stamped steel unit. It's only $15 so I figured it was a cheap experiment.

After swapping it in and checking for precise pulley alignment (a thin shim from the hardware store puts this at the exact same alignment as the stock unit). I started it up and with both heat and headlamps running there is zero belt squeal even when cold.

Problem solved.

I will be swapping out the other alternator pulley for one of these units asap. Also I will take pics showing measurements between the stock pulley and this new one.

Also I want to mention the stock pulley wasn't badly bowed out, the 3/8 gates belt still sat within the groove seemingly OK. However there was a little wobble on the stock pulley.

This may or may not apply, I had a civilian truck with a 6.2 (so did my dad) and both trucks had problems with belts. Gates lasted the longest at about 2 years maybe a bit less. After some research with a friendly NAPA clerk we discovered that there was a "preferred " belt, and all the others were "will fit". I ordered the preferred Gates belt and it had a different shoulder angle to it. It worked well and didn't squeal and lasted for years. My dad finally got one for his and was happy too. No idea if this carried over to CUCV's. Why GM would do something like this is beyond me!

 

[Finnegan1008]

This may or may not apply, I had a civilian truck with a 6.2 (so did my dad) and both trucks had problems with belts. Gates lasted the longest at about 2 years maybe a bit less. After some research with a friendly NAPA clerk we discovered that there was a "preferred " belt, and all the others were "will fit". I ordered the preferred Gates belt and it had a different shoulder angle to it. It worked well and didn't squeal and lasted for years. My dad finally got one for his and was happy too. No idea if this carried over to CUCV's. Why GM would do something like this is beyond me!

Good thing they are easy to change! I have gates belts on there and it was still squealing the drivers alternator even when guitar string tight until I changed that pulley.

The factory pulley had quite a bit of wobble for some reason, this truck has a take out engine from another vehicle I wonder if it got tweaked along the way.