This was written in response to the owner of a 300SD, but is generic to all roller chains.
Timing chain stretch does not exist = it is wear on the pins and bushings = Wear Elongation Measurement.
Chain elongation/wear is not corrected by an offset Woodruff key..
I have stopped checking timing chain elongation/wear on any engine over 250,000 miles, the labor/time is identical to replace the chain.
The cost of a chain is cheap insurance, and generally improves performance.
My rule of thumb is 200-250K miles I replace the timing chain = don't waste money/time checking it..
If the timing has not been changed since new = replacing the timing chain will bring the timing back where it belongs.
IMO: If the chain has measurable elongation/wear = Replace it regardless of mileage!!!
A worn chain is damaging the sprockets.
What is running a damaged/worn out timing chain going to cost ?
At least (by the labor time guide) 4.7 hrs labor + all of these parts....
Crankshaft gear
MB# 617 052 00 03
http://www.pelicanparts.com/cgi-bin/ksearch/pel_search.cgi?SUPERCAT_FLAG=Y&make=MBZ&please_wait=N&forumid=&threadid=&command=DWsearch&descriptio n=617+052+00+03&x=12&y=11
Camshaft gear
MB# 121 052 03 01
http://www.pelicanparts.com/cgi-bin/ksearch/pel_search.cgi?SUPERCAT_FLAG=Y&make=MBZ&please_wait=N&forumid=&threadid=&command=DWsearch&descriptio n=121+052+03+01&I1.x=4&I1.y=6
sprocket gear
MB# 621 050 04 09
http://www.pelicanparts.com/cgi-bin/ksearch/pel_search.cgi?SUPERCAT_FLAG=Y&make=MBZ&please_wait=N&forumid=&threadid=&command=DWsearch&descriptio n=621+050+04+09&I1.x=15&I1.y=6
Timing device
MB# 617 070 05 45
http://www.pelicanparts.com/cgi-bin/ksearch/pel_search.cgi?SUPERCAT_FLAG=Y&make=MBZ&please_wait=N&forumid=&threadid=&command=DWsearch&descriptio n=617+070+05+45&I1.x=7&I1.y=4
Damage cost TOTAL $1,222.00
+ Labor
The
minimum cost of parts for a DIY rebuild is roughly $1550 - $2000 USD.
OM617.952 Rebuild parts list
http://www.peachparts.com/shopforum/showthread.php?t=274085
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There is only one brand of timing chain to use.
Warning, Danger: Please read this thread FIRST...
Need Automotive Grade Prozac
http://www.peachparts.com/shopforum/showthread.php?t=193675
OEM: brand IWIS
Timing Chain, With Master Link Double Row - 136 Links
MB# 003 997 62 94
http://www.pelicanparts.com/cgi-bin/ksearch/pel_search.cgi?SUPERCAT_FLAG=Y&make=MBZ&please_wait=N&forumid=&threadid=&command=DWsearch&descriptio n=003+997+62+94&I1.x=10&I1.y=3&FILTER_997M=ON
The best guide rail is SWAG
MB# 6150500916[
http://www.pelicanparts.com/cgi-bin/ksearch/pel_search.cgi?SUPERCAT_FLAG=Y&make=MBZ&please_wait=N&forumid=&threadid=&command=DWsearch&descriptio n=6150500916&I1.x=15&I1.y=9
upper guide rail
MB# 6150501416
http://www.pelicanparts.com/cgi-bin/ksearch/pel_search.cgi?SUPERCAT_FLAG=Y&make=MBZ&please_wait=N&forumid=&threadid=&command=DWsearch&descriptio n=6150501416&I1.x=10&I1.y=10
lower outer guide rail
MB# 6150521016
http://www.pelicanparts.com/cgi-bin/ksearch/pel_search.cgi?SUPERCAT_FLAG=Y&make=MBZ&please_wait=N&forumid=&threadid=&command=DWsearch&descriptio n=6150521016&I1.x=14&I1.y=5
lower inner guide rail
MB# 6150521116
http://www.pelicanparts.com/cgi-bin/ksearch/pel_search.cgi?SUPERCAT_FLAG=Y&make=MBZ&please_wait=N&forumid=&threadid=&command=DWsearch&descriptio n=6150521116&I1.x=14&I1.y=8
FYI: Links you may need:
PeachParts Mercedes ShopForum > Do It Yourself Links & Resources > DIY Links by Parts Category
Fast navigation Do It Yourself Links
http://www.peachparts.com/shopforum/showthread.php?t=146034
Valve adjustment OM615, 616, 617 FYI.
http://www.peachparts.com/shopforum/showthread.php?t=107729
Need Definitive OM617 Compression Test Procedure
http://www.peachparts.com/shopforum/showthread.php?t=272804
Engine blow-by test, Blow a bag of blow-by
http://www.peachparts.com/shopforum/showthread.php?p=1558819
Diesel Timing Chain Links Thread
http://www.peachparts.com/shopforum/showthread.php?p=1251434
Timing Chains Don't Last Forever
http://www.peachparts.com/shopforum/showthread.php?t=163604
Diesel Injection:
http://www.peachparts.com/shopforum/showthread.php?t=142405