PeachParts Mercedes-Benz Forum - View Single Post

dmorrison · #12 08-17-2003, 08:16 PM

Want to add to this post for futrue reference. I just had the serpentine belt break on the 86 SDL. My wife was driving it and the belt broke in the driveway as she was turning the car around. This car has never stranded us. Its been great. However it would have been nice if it waited a couple of weeks. Saturday our daughter goes to college, she drive the car, and then were getting rid of it. So I just spent the latter part of the afternoon and $28 replacing the belt.
I found that the service maual says you can't remove the fan/clutch assembly without removing the radiator. You can do it without removing the radiator but there are a few tricks.

Your probably going to get the hands a little scratched up
To remove the fan blade/clutch assembly you have to get a small 8mm allen piece for a small socket set. 1/4 drive is best. ( or a small piece of 8mm allen wrench, about 1 inch would work)
If the belt is broken, as mine was, you will have to cut a piece of old belt long enough to fit around the fan pulley. Then use vise grips to clamp down on the ends of old belt. Have about 1 inch of each end so the vice grips can grab them. The pulley will rotate when you try to loosen the 8mm bolt that is holding the clutch/fan assembly on. The vice grips/old belt set up allows you to hold it to loosen the bolt. If your old belt is still on the car, you will just loosen the 8mm bolt.
The reason for the short 8mm allen socket, is if you use a ratchet/allen-socket to loosen the bolt, it will back out so much that you can't get the bolt/ratchet/allensocket assembly out of the radiator/engine opening. Its to long.
So you use the ratchet/allen assembly to loosen the bolt then before it is out so much that it is blocked. You detach the 8mm allen socket and use small vice grips to hold it. Or if you can you can just hold the socket in your hand. I found this was difficult, the bolt was to tight, and using the vice grips was better.
Remove the fan/clutch assembly and the fan shroud.
Loosen the tensioner. The bolt that goes throught the black plastic block. Then unbolt the shock top mount bolt. Remove the shock bolt including the metal plate that holds the black block in position. It will be easier if you unbolt the wire/vacuum tube assembly at the top of the tensioner and get it out of the way.
Then place a round tube or shaft in the hole at the top of the black plastic and rotate the assembly towards the drivers side.
Route the belt through the two large pulleys, ribbed side out. and loop it around the tensioner. Now route it over the power steeting pump, the AC compressor, the crank shaft pully, the fan pully and last the alternator pully.
I found that I had to press down on the tensioner pulley to get the belt to slip on the alternator pulley. Be carefull not to damage the ribbed section that is exposed on the tensioner pulley. I use an old piece of belt and matched the ribbed section to ribbed section. I was able to further push the pulley down to allow the belt to slip on completely.
Attach the tensioner and install the bolts for the tensioner the shock and the wire/vacuum tube harness.

The correct lenght serpentine belt is of course important.
the following is what is listed the the service manual supplement.

With power steering and without AC not usual for a US version
Engine 602-- 2030mm length
Engine 603-- 2080mm lenght

With power steering and AC
Engine 602--2100mm
Engine 603--2145mm
Engine 603.970--2120mm

The layout is attached.

Dave