Another belt snapped! - Page 2 - PeachParts Mercedes-Benz Forum

MBeige · #16 12-05-2011, 03:21 PM

It's also possible, as a general note (not specific to the OP) that the pulleys are skewed (from a previous accident, etc). This will force the pulleys to "wobble" and eat up the belt eventually.

Observe the belts when the engine is idling to ensure minimal play on the pulleys and belt. View them from the side (passenger and driver), shine a light to get better view to make sure it's running smooth. Compare the belts with each other to make sure they're all parallel, this might give a clue as to whether they are in alignment or not.

RANDY P · #17 12-05-2011, 03:25 PM

Yep, or a failing alternator bearing. Could be causing that too. Pulleys dont just go out of alignment unless there is a failure or it sucks up a big rock somehow.

rjp

JimFreeh · #18 12-05-2011, 06:27 PM

Quote:

Originally Posted by LandYaghtLover

In fact when I needed two matching ones for my PS pump it was near impossible. I had to make a couple trips back to the store to get two that actually matched in length. A couple they brought to the desk were not even the same width.

The way to buy paired belts is to look at the batch number printed on the belt. Once you find a match, your pair will age and stretch the same, keeping a nice fit on both belts. I haven't had a problem ordering the Continental belts, used to do this on years ago for other things, like big ventilation fans, and my old 6.3 when I owned it in the seventies.

Jim

dynalow · #19 12-05-2011, 06:47 PM

Quote:

Originally Posted by JimFreeh

That was my first thought as well.

Also, V belts can vary in cross section. The cross section needs to be correct for the belt/pulley interface.

Replacement belts often vary from the original specification in subtle ways not immediately apparent to a casual glance.

If the cross section is not correct, the belt can ride low or high on the sheave causing all sorts of problems. Generic replacement belts can also vary in length from original spec.

Replacement belts are sized to have the greatest number of applications using the lowest number of belts. Often, this means that the belt specc'ed for your car, will not be exactly what the factory installed. It may be slightly longer or shorter, the cross section may be larger/smaller.

Most of the time the difference is negligible, but there are occasions where the need for a factory sized belt is the only option.

I owned a 90 560SEL, and never had a single belt related problem. A good friend owned it prior to me for years, and he never experienced belt failure. He had belts replaced at the dealer, and I only source belts from a MB specific seller when I replace mine.

Thus, I suspect your problem is due to a specific issue with your car, either the alignment of the sheaves, or an inappropriate belt being used.

Addendum:

This is , of course, assuming that you have the correct tension on the belt. You do recheck them a couple of hundred miles after installation, Yes?

Jim

One of the reasons I continue to use the dealer for 30k service, which for my use is every 3 years or so.
"Belt is cracking" Replace it!
Next. ...(and there is always a next and another next and ....

)