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  #1  
Old 07-24-2020, 04:21 PM
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Default Alternator Pulley questions

So, my car threw its alternator belt off. I've acquired a new belt, but noticed that the pulley seems very loose. The shaft is very tight and I currently do not have the correct hand tools to get it lose. However, how could this much movement of the pulley be possible?

I removed the alternator from the car and have two pics showing just how much lateral movement the pulley displays. Or, is this much lateral movement normal and I should just re-install and throw on a new belt?

I appears to be a Bosh AL29X Alternator. It does not appear to be one of the newer de-clutching pullies newer cars have.

Car in question is an '87 924S with AC delete and alternator relocated down using an AC delete bracket.
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Old 07-24-2020, 04:41 PM
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Dave,
I've never encountered that problem, but the play in the pulley does appear to be too much. Is it possible to remove the bolt holding the pulley on? Perhaps a shim is missing underneath, although I don't know if there's supposed to be one. If the whole shaft is moving that much, I'd say the alternator is toast.
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Old 07-24-2020, 04:43 PM
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Yup, something is very wrong there. Can't tell if it's the alternator or the pulley, but there shouldn't be that much movement of the pulley. There really shouldn't be any movement of the pulley or shaft, except to spin. And it should spin freely.
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Old 07-24-2020, 04:48 PM
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Well, the pulley does spin freely. The bolt is tight. The shaft appears to spin both freely and without sign of being bent or wobble. But I can clearly push/pull the pulley 1/8- 1/4 inch as depicted above. I drove the car almost 250 miles home and it was just 20 miles from home when a warning light triggered.. I killed the battery driving home as the alternator was not charging. When i got home, there was no sign of the belt. There was no noticeable noise either at the time of the warning light triggering. In fact, it was while I was starting out at a traffic light.

It would appear there were no shims previously.
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- 1987 944
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- 1978 911 Euro SC
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Old 07-27-2020, 07:50 AM
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After additional observing and consideration, I believe the previous belt was tensioned too tightly. It eventually put stress on the pulley shaft and caused the issue at hand. A replacement (rebuild) unit is on its way. In the meantime, I will need to get this pulley off, as replacement does not come with a pulley. Looks like I need maybe some pass through sockets to get the bolt off? Not sure there is room for a "crows foot" style tool.

Any recommendations for a 24mm pass through socket?
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- 1987 944
- 1987 924S
- 1978 911 Euro SC
- 1976 914 2.0
- 1970 914 1.7 / 2056cc
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Old 07-27-2020, 10:51 AM
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If you have access to a grinder, here's a post on Pelican that describes slightly modding the outside of a 24mm socket so you can hold it with a wrench, while pocking the allen wrench through the 3/8 square opening.

http://forums.pelicanparts.com/porsc...cial-tool.html

Alternatively, if you remove the entire alternator, I'm guessing you can probably find a shop nearby that may have an appropriate tool (like a strut shock top bolt removal tool), to separate it for you.
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Currently
- 1984 944 SP2 racer
- 1977 911 KM Special vintage racer
- 2012 Cayman R (also the wife's)
- 2000 Boxster S (now mine)

- 1995 993 (garage queen)
- 2007 Cayman S (wife's track beast)
- 2017 F350 (tow monster)
- 2018 Jeep Wrangler

Gone but not forgotten
- 1989 944S2
- 1979 RX7
- 1986 944
- 1991 944S2 (in car heaven...)
- 2001 Chevy Suburban 2500 (FIL's beast now)
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  #7  
Old 07-27-2020, 10:54 AM
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If the pulley is tight, too much shaft play due to bad bearing ? Should be able to tell with the belt off pretty quickly.
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Old 07-27-2020, 01:29 PM
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Thanks Tony. Yeah, the alternator is already off the car and on my workbench. I also don't have a grinder/cutting tool.. see.. new car means its tool shopping season!
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- 1970 914-6
Past
- 2000 Boxster
- 1987 944
- 1987 924S
- 1978 911 Euro SC
- 1976 914 2.0
- 1970 914 1.7 / 2056cc
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  #9  
Old 07-28-2020, 08:15 AM
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Quote:
Originally Posted by racer View Post
Thanks Tony. Yeah, the alternator is already off the car and on my workbench. I also don't have a grinder/cutting tool.. see.. new car means its tool shopping season!
Another option to modifying the 24mm socket, is to grip it with socket with a visegrip (presuming you have both ), and see if it'll hold enough for you work the allen wrench.
__________________
- Tony P.

Currently
- 1984 944 SP2 racer
- 1977 911 KM Special vintage racer
- 2012 Cayman R (also the wife's)
- 2000 Boxster S (now mine)

- 1995 993 (garage queen)
- 2007 Cayman S (wife's track beast)
- 2017 F350 (tow monster)
- 2018 Jeep Wrangler

Gone but not forgotten
- 1989 944S2
- 1979 RX7
- 1986 944
- 1991 944S2 (in car heaven...)
- 2001 Chevy Suburban 2500 (FIL's beast now)
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  #10  
Old 07-28-2020, 08:24 AM
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Hit with a couple seconds of impact gun to remove the nut. Is the alternator shaft bad or is the sheave bad?
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