How many miles?
How many miles are on your timing chain? I made an appointment with my neighbors dealership to replace my chain and he told me not to waste my money. According to him diesel timing chains are very reliable and go at least 250k miles without worry. My car only has 165k miles. I trust my neighbor - he sells and services many older Benz's and his wife drives a 300TD. On the other hand I understand the dire implications of the chain letting loose.
Changing the chain is not too difficult. After removing the cover, the old chain is broken using a chain tool (a big version of a bike chain tool). The first link of the new chain is then temporarily linked to the last link of the old chain. The old chain is pulled out keeping tension on the whole thing or it skips out of the tensioners. Next the temporary link is removed along with the old chain and the new chain is linked together. Then the fuel injection timing needs to be checked/adjusted. This requires a unique tool that someone else can explain. Don't remove the engine!
Larry is right, measure to see if the chain needs replacement.
[Edited by jsrmb on 02-19-2001 at 10:22 AM]
1983 300D Turbo
1995 E320 Wagon
2001 MR2 Spyder
2001 Subura WRX Sedan