Belt Chirp after new pulleys
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Belt Chirp after new pulleys
Hello.
I changed both top pulleys on my m273 08 S550. Used a new Continental belt and pulleys from FCP euro, made in France. At first it was fine, but few days later it chirps on start up. Goes away right away if I spray the belt a bit.
I see rock auto has two Continental belts, one has different dimensions. Does that matter? Or is it the tensioner? 118k miles. Tensioner pulley seamed fine.
Thanks
I changed both top pulleys on my m273 08 S550. Used a new Continental belt and pulleys from FCP euro, made in France. At first it was fine, but few days later it chirps on start up. Goes away right away if I spray the belt a bit.
I see rock auto has two Continental belts, one has different dimensions. Does that matter? Or is it the tensioner? 118k miles. Tensioner pulley seamed fine.
Thanks
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S500
I just swapped the tensioner on mine - at 70k miles the bearing was noisy with some play - due to the incompetent design with its stupid shallow retaining bolt, I decided to swap the entire unit rather than just the pulley it needed... I have fitted a Gates unit - new for just $50 so not that fussed
so three top pulleys in 70 k miles, then the next idler and the tensioner on their second - great build quality.
When I swapped the belt on my fathers W211 E class tractor ever since his has always screeched on engine stop. Never bothered to resolve - On mine it never played up when I fitted genuine Merc belts on both cars. The only difference I can see is his has a lot of light surface rust on pulleys - overuse if silicone spray stops his complaining temporarily - I guess the right fix would be to remove dirt, dust, rust etc. from the ribbed pulleys, then spray both pulleys and belt with contact cleaner and refit - I can't be bothered
so three top pulleys in 70 k miles, then the next idler and the tensioner on their second - great build quality.
When I swapped the belt on my fathers W211 E class tractor ever since his has always screeched on engine stop. Never bothered to resolve - On mine it never played up when I fitted genuine Merc belts on both cars. The only difference I can see is his has a lot of light surface rust on pulleys - overuse if silicone spray stops his complaining temporarily - I guess the right fix would be to remove dirt, dust, rust etc. from the ribbed pulleys, then spray both pulleys and belt with contact cleaner and refit - I can't be bothered
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From: Washington, DC
2007 S600, 2007 Chrysler 300 SRT8, 2000 C5 Corvette, 2017 Mustang GT, 2023 300C, and a 2019 Lincoln
If it was me, I'd buy the OEM belt from Mercedes and I'd replace the tensioner (you can get that from FCP for the lifetime warranty). Both are considered maintenance items. I am not there to inspect, but I'd bet a donut your old tensioner is at the end of its useful life and causing the screech on startup.
Please keep us posted on what you do and the results.
Please keep us posted on what you do and the results.
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S500
a combination of grinding paste from the rust remodeled the grooves to the correct shape on the cheap nasty pulleys and the oil on the belt has helped it deform to fit and now there's enough contact to grip....
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Well a day later the new belt started to squeak again. I got tired of spraying It with lubricant and decided to install the old belt I kept.
So far so good. If all goes well and it stays quiet, I’ll order a Mercedes belt which is $46.
the new continental belt will be returned.
So far so good. If all goes well and it stays quiet, I’ll order a Mercedes belt which is $46.
the new continental belt will be returned.
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2007 S600, 2007 Chrysler 300 SRT8, 2000 C5 Corvette, 2017 Mustang GT, 2023 300C, and a 2019 Lincoln
And don't forget to order that tensioner. When it decides to fail completely, it will turn that new belt into shreds. Not expensive.
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Thread Starter
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From: Phoenix
222 S-65
Botus.... For Dad’s Two-Elemon use a toothbrush style wire brush to clean up the multi-vee pulleys as it idles and the underside of the serp belt.
Just a little caution and you won’t lose fingers.
Just a little caution and you won’t lose fingers.
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LOL oops there goes a finger or at minimum, the brush whacks the living beeejuss out of the ones holdng it.. lol
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222 S-65
Worst I've done with the toothbrush wire brushy is have the belt wear some of the plastic handle away. Pull the radiator fan and access is really easy. Just don't let it idle long without and be sure A/C is turned off. Only takes 30 seconds or so to clean them all up.
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2007 S600, 2007 Chrysler 300 SRT8, 2000 C5 Corvette, 2017 Mustang GT, 2023 300C, and a 2019 Lincoln
I'd add a beer to that donut I bet about the tensioner. I am pretty convinced, even at this distance, a new tensioner and an OEM belt will resolve the chirp.
Keep us posted.
Keep us posted.
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S500
the tensioner backing off so much reaching the second retaining bolt is hard work otherwise - not bothering will use 20 mins of your time - doable but more faff than required....
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S500
just thinking my fathers one was silent - but an old belt (I replaced and turned inside out the old one to see it aged and cracking up) - but it then made a noise upsetting my father, who'd never had a peep from the original
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Looks like the new tensioner solved the issue. I put in the New Continental belt that I had and all is quiet during a 2 minute test.
MY hands hurt like hell from wrenching in there, so after a 2 minute idle test I turned it off and walked away from it before the noise came back.
It would be a lot easier with the radiator hose off or fan out the car, but I got it done. Also My hands would not be all black in grease IF the oil filter housing didnt spray oil over the front of the motor because I installed the O ring the wrong way last month.
Thank you all for moral and technical support.
MY hands hurt like hell from wrenching in there, so after a 2 minute idle test I turned it off and walked away from it before the noise came back.
It would be a lot easier with the radiator hose off or fan out the car, but I got it done. Also My hands would not be all black in grease IF the oil filter housing didnt spray oil over the front of the motor because I installed the O ring the wrong way last month.
Thank you all for moral and technical support.
