I have the CS130 GM alt 105 amp
Works great, been using the stock v-belt pulley along with the GM alt fan
I recently bought a dual belt pulley.. the proper way on the shaft would be:
spacer>fan>pulley>lock washer>nut correct?

I cannot do this with the dual belt pulley.. I either have to lose the fan, or lose the lock washer... At the time I went without the lock washer, and now feel uneasy and decided thats probably not a good idea, is it a worse idea to go without the fan?

 

Is the problem shaft length, or alignment? You can fudge alignment by fiddling with spacers, but if the shaft's not long enough, there's not much you can do.

I'd think the fan is necessary, or else the designers would have left it off as an unnecessary cost.

Running without the lockwasher seems risky. At a minimum, use some threadlocker!

Tell me more about this substitution; I'm looking for more amperage, myself.

 

Its just the shaft length.. I stack everything on and doesn't leave enough thread for the nut..
The reason I think of ditching the fan is because this alt is meant for a 90s buick in which it may be mounted in a place with bad ventilation.. where in a FB's bay it should be cooled well, with that monster of a clutch fan 6" away

Theres a thread in the archives about swapping in the GM alt.. it mounts right up no problem, just need to wire the pigtail into the stock harness. The shaft is also bigger so you need to bore out your pulleys for them to fit

 

You need to run the fan...all you have to do is touch an alternator in normal running to appreciate how hot the thing gets, it's not the engine bay, it's the alternator itself and the mechanical heat radiating from the engine block through the brackets generating the heat ~ the diodes and epoxies can only take so much heat. Get a lock nut identical in size and pitch to the alternator nut, put it in your home shop vice with half of the nut above the plane of the jaw face and grind it down...with Threadlock Red on these two nuts locking each other, you should be ok.

 

I was changing the oil in my Jaguar XJR the other day. I noticed this cool looking undercar NACA scoop and ducting. This piqued my curiosity so I followed the duct up and it was to keep the alternator cool.

With this being said, I would think the fan is a must. If you have to lose the lock washer, then un-*** the washer. You can always use some locktite on the nut and you will be golden!

 

Hmm, sounds like I'm gonna be sticking with the fan.

mar3, thanks for the suggestion, that would definitely solve my problem.. but my local hardware stores dont have proper nuts, i've already checked (small city)

I wonder if red loctite on the nut would be enough.. I mean, the engine rotates clockwise, so other than vibration theres no reason the nut should work its way off, I impacted it on

 

Identify the diameter and thread, and look for a stake nut. That way you can safely eliminate the lock washer.

 

Red loctite will be more than enough, you have to heat that stuff with a torch to get it off. In fact, blue loctite will be sufficient especially if you impact the sucker on.