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Alternator pulley R&R

rcamacho

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OK, how the heck do I get the pulley's on and off? From what I've read the nut is ~70Ft/lb. It looks like the fans on the Delco 12SI/17SI do not have enough structural integrity to be useful for clamping, etc. I have an impact gun but it seems like the alternator will just rotate and get me nowhere.
 
Take a pair of pliers and hold the fan, impact and spin the nut off, and pull it off....easy as pie.

Hell I used to use an electric impact when I worked at the parts store.
 
I destroyed the fan on the alternator I had.

Are you trying to remove it with the belt still attached and super tight? With an impact that should come off.

The fans on the later alternators are plastic with a thin piece of steel on the front and back. Neither the metal nor the plastic blades will handle any sort of force on them without breaking or bending from my experience.

Does yours use the allan key in the shaft to hold it in place? With two people and a wrench/allan key, you can PROBABLY get it off with some effort. It took me awhile.
 
dyeager535 said:
I destroyed the fan on the alternator I had.

Are you trying to remove it with the belt still attached and super tight? With an impact that should come off.

The fans on the later alternators are plastic with a thin piece of steel on the front and back. Neither the metal nor the plastic blades will handle any sort of force on them without breaking or bending from my experience.

Does yours use the allan key in the shaft to hold it in place? With two people and a wrench/allan key, you can PROBABLY get it off with some effort. It took me awhile.

I'm trying to remove the pulley with the alternator off the vehicle. Both alternators have an allen key slot on the shaft. I've tried using an allen key and an open end wrench to loosen the nut to no avail.
 
Yep, two person method is about the only way I can make the allan key/wrench work.

Don't waste time with an open end, they just flare out when you put enough force on them, use a box end.
 
dyeager535 said:
Yep, two person method is about the only way I can make the allan key/wrench work.

Don't waste time with an open end, they just flare out when you put enough force on them, use a box end.

My bad, I mean't box end.
 
Allen key a waste of time!

I have had success removing altenator pulleys with a good air impact wrench,and nothing else-I just wrap a rag around the fan and hold it by hand,or use heavy gloves,-I've wrecked a few trying to use an allen wrench in the shaft,and holding it in a vise and using a box wrench--but the impact usually zips it right off with no sweat--
I had to change a good many pulleys at the parts store on a saturday afternoon--many stores would not sell someone an altenator just because the pulley was the wrong one for the application,I would just zip the customers old pulley off,and install it on the new altenator--my boss freaked when I took one altenator apart and "clocked" it,so the plug would be in the right spot!--guess he had no faith in my mechanical abilities!--but he liked the 150 bucks I put in the register by "saving" the sale--..:crazy:
 
diesel4me said:
I have had success removing altenator pulleys with a good air impact wrench,and nothing else-I just wrap a rag around the fan and hold it by hand,or use heavy gloves,-I've wrecked a few trying to use an allen wrench in the shaft,and holding it in a vise and using a box wrench--but the impact usually zips it right off with no sweat--
I had to change a good many pulleys at the parts store on a saturday afternoon--many stores would not sell someone an altenator just because the pulley was the wrong one for the application,I would just zip the customers old pulley off,and install it on the new altenator--my boss freaked when I took one altenator apart and "clocked" it,so the plug would be in the right spot!--guess he had no faith in my mechanical abilities!--but he liked the 150 bucks I put in the register by "saving" the sale--..:crazy:

Thanks for the suggestion. I'll give it a try.
 
diesel4me said:
I have had success removing altenator pulleys with a good air impact wrench,and nothing else-I just wrap a rag around the fan and hold it by hand,or use heavy gloves,-I've wrecked a few trying to use an allen wrench in the shaft,and holding it in a vise and using a box wrench--but the impact usually zips it right off with no sweat--
I had to change a good many pulleys at the parts store on a saturday afternoon--many stores would not sell someone an altenator just because the pulley was the wrong one for the application,I would just zip the customers old pulley off,and install it on the new altenator--my boss freaked when I took one altenator apart and "clocked" it,so the plug would be in the right spot!--guess he had no faith in my mechanical abilities!--but he liked the 150 bucks I put in the register by "saving" the sale--..:crazy:

I used my air impact gun on the pulley this evening, it worked like a charm. Thanks for the tip.
 
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