Serpentine Tensioner failure
#1
Member
Thread Starter
Serpentine Tensioner failure
Awhile back I did a post about replacing serpentine components on a E320 - see: https://mbworld.org/forums/e-class-w...ft-pulley.html
In that post I referenced this 2001 E430 which needed the same work. Well - I put if off - daughter moved away - blah blah blah. Flash forward to a month ago. Daughter is back in our area, but I still had not replaced those serpentine components..
On her way home (late at night, bartender) I get the call - weird squealing sound up front, smells like rubber, hard to turn steering wheel, alternator warning on dash. Sounds like a serpentine belt to me. She makes it home and the next day I review the issues. Belt was fully off the wheels, had a burnt section, and the tensioner was all messed up. Here is what I got after pulling it apart:
The sealed bearing on the wheel on the tensioner had basically self destructed. I only found 4 of the ball-bearings, and look at those seals and races.
The repair was simple enough, new belt, new tensioner, new idle wheel (spinning it - it sounded like all of the grease in the sealed bearings was gone) so good time to replace it.
Did not replace the crank pully - it is still fine (at least it looks fine and no visible wobble).
And I did replace the air conditioning compressor awhile back and should have replaced both of these then, but did not... So for those of you that have not replaced these and they are still original - just do it. I used the ones from fcp euro since those same ones have worked well in the E320 which is still going strong.
In that post I referenced this 2001 E430 which needed the same work. Well - I put if off - daughter moved away - blah blah blah. Flash forward to a month ago. Daughter is back in our area, but I still had not replaced those serpentine components..
On her way home (late at night, bartender) I get the call - weird squealing sound up front, smells like rubber, hard to turn steering wheel, alternator warning on dash. Sounds like a serpentine belt to me. She makes it home and the next day I review the issues. Belt was fully off the wheels, had a burnt section, and the tensioner was all messed up. Here is what I got after pulling it apart:
The sealed bearing on the wheel on the tensioner had basically self destructed. I only found 4 of the ball-bearings, and look at those seals and races.
The repair was simple enough, new belt, new tensioner, new idle wheel (spinning it - it sounded like all of the grease in the sealed bearings was gone) so good time to replace it.
Did not replace the crank pully - it is still fine (at least it looks fine and no visible wobble).
And I did replace the air conditioning compressor awhile back and should have replaced both of these then, but did not... So for those of you that have not replaced these and they are still original - just do it. I used the ones from fcp euro since those same ones have worked well in the E320 which is still going strong.
Last edited by tyabnet; 05-19-2023 at 07:51 PM.
The following 2 users liked this post by tyabnet:
Bdevil82 (07-17-2023),
TheExecutive (06-22-2023)
#2
Newbie
This sounds like a issue I've just encountered on my new '99 E430. I see your old post about all parts and tools. Thanks for the posts!!
Last edited by TheExecutive; 06-22-2023 at 11:35 PM.