Wtf tensioner pulley disintegrated on highway!!
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2007 Mercedes E550
Wtf tensioner pulley disintegrated on highway!!
Driving to my parents Christmas Eve, I noticed a clatter sound from my engine. My power steering was gone and alternator light came on. I still had power on gas pedal. Fortunately was just a mile from the house. I opened my hood and to my great surprise my drive belt was shredded. Then I looked at the tendioner pulley and it was in gone! No plastic portion of the pulley at all! See pics! Im going to the dealer Monday to get the pulley and belt!
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2005 C230K Sport Coupe
Ouch!
I'm glad you didn't have to go far!
On the M271 engine, there's one serpentine belt, and it also drives the water pump. So, when that belt goes, there's no water pump, and there's near zero cooling of the engine (just by heat conduction in the stationary water - there's very little convection).
Fwiw, for others, what the typical belt, pulleys, and belt routing looks like.
The water pump is under the big pulley with the 4 bolts.
Back to wrapping presents...
I'm glad you didn't have to go far!
On the M271 engine, there's one serpentine belt, and it also drives the water pump. So, when that belt goes, there's no water pump, and there's near zero cooling of the engine (just by heat conduction in the stationary water - there's very little convection).
Fwiw, for others, what the typical belt, pulleys, and belt routing looks like.
The water pump is under the big pulley with the 4 bolts.
Back to wrapping presents...
Last edited by RedGray; Dec 24, 2016 at 06:09 PM.
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W203 c200 Kompressor
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Merry xmass
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Removed the supercharger baffle today (while drinking my xmass beers) to find it was loose and clearly rubbed again the belt that caused it to shred!!
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Check the alternator pulley one way clutch by sticking something through the front and try to rotate the inner fins. They should rotate one way and not the other. If they don't rotate at all then it's locked up and causes strain on the belt system. Also check to see if the ac compressor seized up.
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2007 Mercedes E550
Check the alternator pulley one way clutch by sticking something through the front and try to rotate the inner fins. They should rotate one way and not the other. If they don't rotate at all then it's locked up and causes strain on the belt system. Also check to see if the ac compressor seized up.
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2007 Mercedes E550
Bad luck continues
Today my control arm felt intense vibration. I know it was the control arm because the other side went bad a few years ago. So to add insult to injury, I had a second repair this week. On the bright side, the guys at merchants fixed it quickly for a relatively low price.
The mecganic also said that my experience with the bad tensioner pulley is very common, and he repairs 4 or 5 of these a week..
The mecganic also said that my experience with the bad tensioner pulley is very common, and he repairs 4 or 5 of these a week..
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From: New England! :-)
2005 C230K Sport Coupe
Thanks!
I'm already replacing the tensioner and pulley in my restoration project.
Sounds like a good idea to do the belt, tensioner, and pulley at 50K mile intervals, when I'll also be replacing the timing chain.
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Check the alternator pulley one way clutch by sticking something through the front and try to rotate the inner fins. They should rotate one way and not the other. If they don't rotate at all then it's locked up and causes strain on the belt system. Also check to see if the ac compressor seized up.
Does the belt have to be off to check the alternator pulley? Do you just stick a normal flat head screw driver to see if seized? Or need a spline tool? What spline tool?
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E55
Belt stays on. Anything that you can reach into the front of the alternator to try and spin the internal fins will work.
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Checked the alternator pulley clutch tonight, it was really easy. The clutch went clockwise but not the other way, so I guess the pulley is fine. Many thanks!
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