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3G alternator bracket question

tampabronco

Sr. Member
Joined
Jan 10, 2011
Messages
458
Looking at going with the 94 Ford taurus alternator and wondering if the stock bottom bracket is long enough? Where the bottom of the alternator slides. V belt set up

I'm thinking the 3G alternator is 8.25 between mounting holes.

Or do I need to find a longer bracket
 
Last edited:

DirtDonk

Contributor
Bronco Guru
Joined
Nov 3, 2003
Messages
49,366
Well most report being able to bolt them right on. Even the large version. Typically the only ones we hear of having problems are those with the original bracket that was a dual purpose alternator and air pump mount. Those require either heavy modification or replacement with the standard style.
But most report being able to bolt them right on. Even the large version.
But it sounds from your description like you have the standard style. That would be one roughly triangular shape bracket and one curved adjusting arm. That’s what you have? Then in theory it should work as is.

When I replaced my original with a large case 1G alternator I added a little extra length to the slot to get full adjustment with the belt I had. A slightly shorter belt would probably have avoided that modification, but it’s been so long I can’t remember if I ran into another issue that required the longer slot or not.

I guess at this point all you can do is give it a try. I’m sure others will chime in with their experiences. Maybe we’ll get lucky and run into somebody that actually did have an issue and they can say what they went through.
 
OP
OP
tampabronco

tampabronco

Sr. Member
Joined
Jan 10, 2011
Messages
458
Well most report being able to bolt them right on. Even the large version. Typically the only ones we hear of having problems are those with the original bracket that was a dual purpose alternator and air pump mount. Those require either heavy modification or replacement with the standard style.
But most report being able to bolt them right on. Even the large version.
But it sounds from your description like you have the standard style. That would be one roughly triangular shape bracket and one curved adjusting arm. That’s what you have? Then in theory it should work as is.

When I replaced my original with a large case 1G alternator I added a little extra length to the slot to get full adjustment with the belt I had. A slightly shorter belt would probably have avoided that modification, but it’s been so long I can’t remember if I ran into another issue that required the longer slot or not.

I guess at this point all you can do is give it a try. I’m sure others will chime in with their experiences. Maybe we’ll get lucky and run into somebody that actually did have an issue and they can say what they went through.
Thanks for the input! I'm going to do some measuring and see what happens... For me, what should be a 30 minute job usually take 3 hours.. More info before hand is always helpful
 

DirtDonk

Contributor
Bronco Guru
Joined
Nov 3, 2003
Messages
49,366
Oh I understand completely. That 30 minute job often takes me all day!
I mean, after all... Ya gotta clean and paint everything around it and inspect and admire everything else within a 3 foot radius. Right?;)

paul:rolleyes:
 

Jdgephar

Bronco Guru
Joined
Sep 25, 2012
Messages
1,384
...and then the right pulleys, to fix the belt squeal...

Sent from my SM-G981U using Tapatalk
 

DirtDonk

Contributor
Bronco Guru
Joined
Nov 3, 2003
Messages
49,366
Ahhh yes, how could I forget that…
Either dual groove, larger diameter (or both), or full serpentine swap.
 

DirtDonk

Contributor
Bronco Guru
Joined
Nov 3, 2003
Messages
49,366
Yes you can. And you may get lucky and not have any squeal, but quite often the stock bronco V belt pulley does not have enough grip with its belt so that during initial start up, especially on wet mornings, you’ll get some belt squeal until the belt traction catches up with the alternator.

If that’s the case, you don’t really want to compensate for it by over tightening because then it just wears out the bearings prematurely. But a larger diameter pulley has more grip and leverage so usually doesn’t squeal. It doesn’t slow the alternator down enough to cause any charging problems usually, but if that’s a concern you can keep the same diameter pulley and just use a dual sheave version.
Depending on what year your bronco is, you might already have dual groove pulleys on the crank and water pump. That usually makes life easier.
But all this assumes you have a problem after the install. Best to finish the install and light it up and see how it works.
 
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