97 320 serpentine belt replacement

[DGoff]

I have a 97 320 and would like to change my drive belt. Any advise would be apppreciated....

[hudsmore]

Remove the 2-piece fan shroud. Slacken the tesion adjusting nut until the little arrow on the tensioner moves to the right. The thread on this nut is revese threaded and adjusts tension by being extended so you need to shorten it by turning it to the LEFT. Once slackened you should be able to slip the old belt off and install the new one. MAKE SURE YOU HAVE THE RIGHT SIZE BELT!!! (On my 300sl its 2440) Be very careful as you re tension as the bolt has a limited throw and if you extend it past its end it will strip. I actually modified mine and replaced the bolt with threaded rod and re-tapped the nut. Tighten the the belt by turning the nut to the RIGHT until the little arrow on the tensioner unit moves left to the little hash mark.

Come to think of it, when I did mine, I had the fan off as well and am not sure if this is required. It is only one Allen nut (10mm?) but you need a thin spanner to hold the pulley while you turn it. (One of those Bob Villa strap wrenches might work also.) Torque spec on this nut is about 55ftlbs I think.

Good Luck.