Parts Catalog Accessories Catalog Tech Info Tech Forums
  Search our site:    
 Cart  | Project List | Order Status | Help    

Go Back   PeachParts Mercedes ShopForum > Technical Information and Support > Tech Help

LinkBack Thread Tools Display Modes
Old 10-15-2003, 09:22 PM
fz500sel's Avatar
Happy now in paradise!
Join Date: Nov 1999
Location: Venice, FL - "sharktooth capital of the world"
Posts: 712
Tensioner bad?

The vehicle is a 1990 350SDL (without bent connecting rods).

Low rumbling starting in the front of the engine. Stops at acceleration. Figured it is the serpentine belt tensioner shock bushings starting to go even tho, they have been replaced about 8,000 miles ago.

I went to look at the shock and tensioner assembly and noticed that the tensioner is NOT parallel with the belt. Is this a problem I should be worried about in the future or is it normal? I never noticed whether it was parallel before or not.
Attached Thumbnails
Tensioner bad?-image54.jpg  
85 300D 310K (sold)
90 350SDL 184K sold
83 300D 118K (sold)
88 300E 153k (sold)
93 400E 105K (sold)
Reply With Quote
Old 10-16-2003, 12:24 AM
Registered User
Join Date: Jan 2001
Location: California
Posts: 2,068
If the tensioner is not parallel with the belt, CHANGE IT ASAP. Replace the belt shock too.
Reply With Quote
Old 10-16-2003, 01:15 AM
Larry Delor's Avatar
What, Me Worry?
Join Date: Jun 1999
Location: Sarasota, Fl.
Posts: 3,026
Seeing as how you are about to drive around 1300 miles, and probably do not have time to fix it, I would grab a spare belt for along the way, and what ever tools you might need to change the belt. Seems kinda weird that it is doing that. I wonder if its the bracket, or that the tensioner wheel itself is crooked.
"...rationality of thought imposes a limit on a person's concept of his relation to the cosmos." -Nash

04/71 280SE 195k
09 Jetta TDI
Reply With Quote
Old 10-16-2003, 02:54 AM
Registered User
Join Date: Jan 2001
Location: California
Posts: 2,068
On the diesel OM60x motors, if the belt tensioner breaks, the entire timing case can get torn up and the engine is more or less done for. You will be screwed. Get that taken care of ASAP - especially before you take that road trip.

Quoted from

"...check that the serpentine belt idler pulley (right below the horizontal expanse of fan belt at the front to of the engine) MUST be aligned parallel with the belt - if it's a degree or two cocked, then it MUST be repaired..."

Note the emphasis on MUST.
Reply With Quote
Old 10-16-2003, 07:56 AM
Live to Learn
Join Date: Mar 2002
Location: Raleigh NC
Posts: 145
Repair it or have it repaired before you go. It will take much less time now than later when you have to call a tow truck, find a competent shop, and them get the parts if they dont have them in stock. I have seen this many times and it will not last that long.
Mercedes Benz Master Tech
ASE Master Technician
Diagnostic Technician
Owner of "Behind the Star Inc."
Raleigh NC.
Reply With Quote


Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On

All times are GMT -4. The time now is 02:16 AM.

Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2016, vBulletin Solutions, Inc.
Search Engine Optimization by vBSEO 3.6.0
Copyright 2011 Pelican Parts - Posts may be archived for display on the Peach Parts or Pelican Parts Website -    DMCA Registered Agent Contact Page