Mercedes: Mercedes, crank shaft, cam shaft

Question
Hi, I have a 1977 240 D Mercedes. It has the York style AC compresser(which is up on top) and I am replacing the timing chain and tensioner and was wonder if the tensioner can be replaced without removing the AC compresser. Thanks

Answer
A correctly rolled on timing chain = remove the valve cover, remove the chain tensioner, break the old chain in the correct location, join the old/new chains, very slowly rotate the crank shaft (one cam tooth per movement), until the new chain meets itself at the top of the cam shaft.
Extreme caution/precaution must be exercised.

If you have never done this, it can be dangerous to your engine.
If you drop the chain into the engine = extreme bad news.
If the cam slips = extreme bad news.

More data for you.

Have been told that timing chains do not need replaced until rapping noise begins?
http://www.mercedesshop.com/shopforum/showthread.php?p=879369#post879369