Alternator pulley
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Pro
Joined: Jan 2008
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From: New Jersey
Alternator pulley
Anybody know the theory behind the operation of the alternator pulley. It's not a solid drive but whats called a decoupling pulley. Seems to have a fluid coupling or some kind of clutch mechanism. Found that out when I had to remove one and needed a special tool called a alternator decoupling pulley tool. The tool has 33 splines to engage the pulley and then is hollow to allow a Torx-50 to hold the shaft from turning.
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Le Mans Master
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From: West coast CA
Anybody know the theory behind the operation of the alternator pulley. It's not a solid drive but whats called a decoupling pulley. Seems to have a fluid coupling or some kind of clutch mechanism. Found that out when I had to remove one and needed a special tool called a alternator decoupling pulley tool. The tool has 33 splines to engage the pulley and then is hollow to allow a Torx-50 to hold the shaft from turning.
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Anybody know the theory behind the operation of the alternator pulley. It's not a solid drive but whats called a decoupling pulley. Seems to have a fluid coupling or some kind of clutch mechanism. Found that out when I had to remove one and needed a special tool called a alternator decoupling pulley tool. The tool has 33 splines to engage the pulley and then is hollow to allow a Torx-50 to hold the shaft from turning.
Here's all about decoupler pulleys from the company that makes them:
http://www.decouplerpulley.com/basics.cfm
And from an alternator and starter supply company:
http://www.metroplexalternator.com/pulleys.html
More than you ever wanted to know about alternator pulleys.
Last edited by wjnjr; May 18, 2023 at 10:05 AM.
Drifting
Joined: May 2019
Posts: 1,736
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From: Lakeland, Florida
I have 2012 M6. A month or so ago i did a hard pull and it spun the alternator pulley loose and the belt came off. The pulley had separated from the shaft completely. It was the original alternator.
I called a stealership then my Corvette mechanic. The stealership did a history search and discovered the part number for M6 alternator has been superseded/sunsetted by the A6 alternator part nbr
25888970
The only new ACDelco alternator available is the part number for the alternator used on A6 cars with the clutch style 25888970. Thats what i installed the A6 alternator - zero problems.
I called a stealership then my Corvette mechanic. The stealership did a history search and discovered the part number for M6 alternator has been superseded/sunsetted by the A6 alternator part nbr
25888970
The only new ACDelco alternator available is the part number for the alternator used on A6 cars with the clutch style 25888970. Thats what i installed the A6 alternator - zero problems.
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