My 1995 S420 now has 61,000 miles on the clock, and I'd like to replace the serpentine belt. Would anyone know the procedure? Thanks!

You have to remove the fan and shroud. Then, assuming you have a late style spring tensioner, you will hold the tensioner back with a 15mm offset wrench and take off the belt. You'd better remember how it came off though. IT can go on many ways that are wrong, only one is correct.

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Benzmac:
Donnie Drummonds
ASE CERTIFIED MASTER AUTO TECHNICIAN
MERCEDES SPECIALIST 11 YRS

Donnie, thanks for the info. I took a look at the tensioner, but don't see any bolthead(?) that the 15 mm wrench would be used on. What other possible way might I move the tensioner (i.e., if I have an old style tensioner)? Also, did you recommend removing the fan and fan shroud because there is not enough clearance to get the belt on otherwise? Thanks

If you have the new style spring tensioner, there will be a 15mm nut in the center of the tensioner pulley. IF you have the old style, you will have a tensioning rod. If this is the case, you will have to loosen the clamp bolt (10mm allen) that is just below the pulley and then loosen the adjustment rod.

I usually replace the tensioners on the 119 engine. I have had many, many of them fail at bad times.

__________________
Benzmac:
Donnie Drummonds
ASE CERTIFIED MASTER AUTO TECHNICIAN
MERCEDES SPECIALIST 11 YRS

Donnie:

I am thinking about changing the belt in my S320 1994. But, is it necesary to take the fan off. A drawing or picture showing where the tensioner and the bolt that needs to be loosen would greatly help me. Once again thank you.

The snout on my tensioner has a torx bit looking fitting that was easily gripped by a 12pt socket. I don't remember what size.

Sixto
95 S420
91 300SE
87 300SDL
83 300SD

I never remove the fan to change my belt, just take the shroud off then get a round bar to pry the tensioner over while you remove the bolt.

__________________
1995 S-350
370K + SOLD
1952 220B Cabriolet
39K kilometers + SOLD
1998 E300D
310K +
2012 E350 BlueTec
120K

oldsouth,

That works on the SDL. The S420 set-up is more like the GM/Chrysler V6 set-up.

Come to think of it, I don't recall pulling the fan. I think I just hung the shroud on the fan.

Sixto
95 S420
91 300SE
87 300SDL
83 300SD

I've got the old style tensioner. I've found the 10mm allen head but i have no clue what the adjustment rod is. Any help would be greatly appreciated.

This article may help...

http://v12uberalles.com/Water_Pump.htm

__________________
1995 S600, 1 of 618 (sold)

"Speed is just a question of money...how fast you wanna go?"

LONG LIVE THE W140!
Visit my Web Page at www.v12uberalles.com

Check your "owners manual", there's a picture of the proper belt orientation and the location of the belt tensioner; #1 for my car. Pic on page "121".

__________________
Regards . . . . JimF
-------------------
'94 S500 Cpe

Visit my Mercedes Web Page

resurrecting an old thread because this thread is what my search found and to thank Benzmac for the useful post.

also note, as sixto says, some have a Torx E10 nut. --Fwiw, my 1997 S320 has the standard 15mm hex nut.



The belt can be replaced w/o removing the fan or shroud.

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