Alternator tensioner-thing?

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AuroraGirl

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Hardly in photo, but still visible. Is there a p/n or a name for that bolt? I tried googling a few options but couldnt find any. its currently rigged with a bolt, washers, and a nut. It also appears to have bent the bracket a bit(might need a new bracket?). Id rather it be proper so when I put new belts on I dont have it putting torsional force on my belts like it currently is. Also, so it doesnt hit my alternator and seize it in place while the belt smokes. Dont ask me how that happened... haha!

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PrairieDrifter

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I'm guessing the hole on the alternator is stripped, will most likely need a new alternator, then the bolt should come with the alt. If not I believe it's just a 3/8 bolt.
 

AuroraGirl

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I'm guessing the hole on the alternator is stripped, will most likely need a new alternator, then the bolt should come with the alt. If not I believe it's just a 3/8 bolt.
The alternator is threaded and its just a bolt? If thats the case, the original bolt might be gone and its just a replacement my grandpa threw in with washers... he was strange. A new alternator does not seem like a bad idea, this one struggles.
 

Poppy 87

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The alternator is threaded and its just a bolt? If thats the case, the original bolt might be gone and its just a replacement my grandpa threw in with washers... he was strange. A new alternator does not seem like a bad idea, this one struggles.
If the alternator is okay, I'd use a heli-coil if the thread is damaged
 

PrairieDrifter

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A new alt is like 50 bucks and if the one on the truck is original or close to it might be worth it. But if the threads are fine and it works fine then no harm.
 

PrairieDrifter

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The alternator is threaded and its just a bolt? If thats the case, the original bolt might be gone and its just a replacement my grandpa threw in with washers... he was strange. A new alternator does not seem like a bad idea, this one struggles.
It should have one washer.
 

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To be on the safe side, if you happen to ever get one from the boneyard always take that bolt with the alternator. At some time, I don't know what year, they changed to metric size.
 

AuroraGirl

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To be on the safe side, if you happen to ever get one from the boneyard always take that bolt with the alternator. At some time, I don't know what year, they changed to metric size.
Huh. Weird. So if i bought a new one, it might not work? I dont know what year this engine is out of. I could alwyas pulls the alternator and find a casting #
 

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To be on the safe side, if you happen to ever get one from the boneyard always take that bolt with the alternator. At some time, I don't know what year, they changed to metric size.

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The Metric system has always just been an inconvenience.

Especially on the GMT 400's where the inconsistency just pisses me off.
 

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The Metric system has always just been an inconvenience.

Especially on the GMT 400's where the inconsistency just pisses me off.

Not just the GMT400's. My 86 Sub is that way. I swear some moron used metric on half and SAE on the other half. No rhyme or reason to it either.
Very much a PITA.
 

Snoots

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IIRC, all of the SI types use SAE threads and CS and AD types use metric.

AHA! Found 'em!


3/8 - 16 x 1.0"
or
M10 - 1.5 x 30mm
 
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DoubleDingo

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If you take in your old one they can easily match it up with a new one.
 

75gmck25

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I swapped a 94 amps V-belt 12si to get some more charge amps, and IIRC the threaded hole in the adjuster is metric. However, my alternator is from a newer GM car, not a truck.

Bruce

Bruce
 

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