Belt issues
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CLK 350
Belt issues
350 CLK - W209
There was a chirping sound coming from under the hood. After reading some threads it was easy to diagnose the issue as bad bearings in the idler pulley. I replaced it with no problem on Sunday and it immediately fixed the issue. Drove the car Sunday and Monday with no problems.
Started the car up this morning, and there was a new chirping sound different from the original one that did not go away until I was on the highway for a good 5 minutes. Got to work, parked, and could smell a burning scent coming from under the hood. I have not had a chance yet to do any digging into this, but does anyone know off the top of their head what might be causing this? Could replacing the idler pulley have put new stress on a different part or something? Or could I have messed up the belt somehow? Or maybe the new idler pulley is defective? It's just weird that the symptoms did not show up until 2 days later.
There was a chirping sound coming from under the hood. After reading some threads it was easy to diagnose the issue as bad bearings in the idler pulley. I replaced it with no problem on Sunday and it immediately fixed the issue. Drove the car Sunday and Monday with no problems.
Started the car up this morning, and there was a new chirping sound different from the original one that did not go away until I was on the highway for a good 5 minutes. Got to work, parked, and could smell a burning scent coming from under the hood. I have not had a chance yet to do any digging into this, but does anyone know off the top of their head what might be causing this? Could replacing the idler pulley have put new stress on a different part or something? Or could I have messed up the belt somehow? Or maybe the new idler pulley is defective? It's just weird that the symptoms did not show up until 2 days later.
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2008 CLK550 Cab
Changing a pulley will not stress something else I do not think. I suppose if the original problem was that the tension in the spring-loaded arm was bad, then a new arm will put more tension on the belt. But I'm guessing your problem was not that, but a pulley with a bad bearing. The belt routing is pretty complex, and I do not know if it is even possible to route it wrong, and still have it "fit." But a bad idler will not normally make a burning smell. So my first suspicion is the belt is rubbing something. You need to inspect the belt, running and not, and see what is happening.
