Bad Alternator Sprag Bearing Took Out AC
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Joined: Oct 2004
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From: Las Vegas, Nevada
2013 C350 Coupe, 2005 C230K Kleemann Sedan, 2013 GLK350 4matic
Bad Alternator Sprag Bearing Took Out AC
This is on my 2005 C230 Sport Sedan:
Well...I new it was coming. Had the squealing of the drive belt, and I have been meaning to get the new alternator pulley replaced. My luck ran out when backing out of my garage, I heard something shear and no cold air from the ac.
I had this happen back in 2008 when I just went out of warranty. 80,000 miles later, I should have known I was rolling the dice.
Off to order a rebuilt alternator, then to take it to the ac shop to have the ac pulley replaced. I hope the bill doesn't set me too far back.
And here in Las Vegas, its been over 110 degrees or higher the past week...oh boy.....
Well...I new it was coming. Had the squealing of the drive belt, and I have been meaning to get the new alternator pulley replaced. My luck ran out when backing out of my garage, I heard something shear and no cold air from the ac.
I had this happen back in 2008 when I just went out of warranty. 80,000 miles later, I should have known I was rolling the dice.
Off to order a rebuilt alternator, then to take it to the ac shop to have the ac pulley replaced. I hope the bill doesn't set me too far back.
And here in Las Vegas, its been over 110 degrees or higher the past week...oh boy.....
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Joined: Dec 2003
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From: BC, Canada
2003 C230K Coupe Orion Blue
I still don't quite get how the alternator sprag pulley can take out the compressor. Can someone please explain?
My belt actually squeaked for several (I'm going to guess 8) years before I decided to tackle it earlier this year with a new belt and sprag pulley. With that said though, where I live it's only AC season 3 months out of the year. With the new parts installed, the chirping noise is definitely gone, but the idle is also noticeably rougher, with lower RPM.
No idea how you guys survive near the equator. I would melt.
My belt actually squeaked for several (I'm going to guess 8) years before I decided to tackle it earlier this year with a new belt and sprag pulley. With that said though, where I live it's only AC season 3 months out of the year. With the new parts installed, the chirping noise is definitely gone, but the idle is also noticeably rougher, with lower RPM.
No idea how you guys survive near the equator. I would melt.
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Joined: May 2017
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C320
The OAP pulley is really easy to replace on the car without even removing the alternator from the car. A lot of us with older diesels retrofitted this type of pulley onto our cars. It extends the life of the belt and tensioner and makes the whole belt drive a lot quieter.
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Joined: Oct 2013
Posts: 527
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From: Carolinas
2005 C230K SS
I still don't quite get how the alternator sprag pulley can take out the compressor. Can someone please explain?
My belt actually squeaked for several (I'm going to guess 8) years before I decided to tackle it earlier this year with a new belt and sprag pulley. With that said though, where I live it's only AC season 3 months out of the year. With the new parts installed, the chirping noise is definitely gone, but the idle is also noticeably rougher, with lower RPM.
No idea how you guys survive near the equator. I would melt.
My belt actually squeaked for several (I'm going to guess 8) years before I decided to tackle it earlier this year with a new belt and sprag pulley. With that said though, where I live it's only AC season 3 months out of the year. With the new parts installed, the chirping noise is definitely gone, but the idle is also noticeably rougher, with lower RPM.
No idea how you guys survive near the equator. I would melt.
It's good preventive maintenance to frequently check the alternator pulley for proper clutch operation.
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Joined: Dec 2003
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From: BC, Canada
2003 C230K Coupe Orion Blue
^ That's what I'm saying though. My pulley was bad (seized) for several years and the AC still works fine. Obviously that wouldn't be the best situation, but I don't get how an AC compressor can fail from slight variations in RPM caused by the seized alternator pulley. Not like the pulley is going backwards or anything. Also the AC compressor on the M271 is several pulleys removed from the alternator.
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MBWorld Fanatic!
Joined: Oct 2004
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From: Las Vegas, Nevada
2013 C350 Coupe, 2005 C230K Kleemann Sedan, 2013 GLK350 4matic
^ That's what I'm saying though. My pulley was bad (seized) for several years and the AC still works fine. Obviously that wouldn't be the best situation, but I don't get how an AC compressor can fail from slight variations in RPM caused by the seized alternator pulley. Not like the pulley is going backwards or anything. Also the AC compressor on the M271 is several pulleys removed from the alternator.
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Joined: Sep 2011
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From: Austin, TX
2005 C230K(sold), Mk7 Jetta
By the violent sounds and vibrations the belt makes when the alt pulley seized, I very much believe it will shear the cr-p out of anything that's not rock solid...
.. of course, the dealer would replace the whole AC compressor
I was suspecting it was possible to replace just the pulley, but not much info / kits around.
.. of course, the dealer would replace the whole AC compressor
I was suspecting it was possible to replace just the pulley, but not much info / kits around.
