Just before the new year I did a valve adjustment so I took some pics to get an idea how much the chain has stretched since last time.

I will say that after six or so oil changes using mobil 1 every 3K miles - my valve train is looking sooo much cleaner than before:

What is this inside my valve cover? (Soot / Crud Rock?)

First pic - the valve train - looking better

Second pic - lining up the timing marks

Third pic - how the crank lined up first time around

Fourth pic - how the crank lined up the second time around

What do you think about the stretch??? Still OK??

Car has 209K miles.

Attached Thumbnails

       

__________________
~shell
As of 2/2010:
2001 CLK55 0o\=*=/o0
13.6 @ 106mph
10K mi
1984 300SD
260K mi and going and going...
97 S600
46K miles
1991 Sentra SE-R (extremely dorked with)
www.se-r.net

Man that is one clean engine! Does one read the stretch from the flat side or the slanted side? Either way its less than five degrees, which is good for the original chain.

__________________
Seth

1984 300D 225K
1985 300D Donor body
1985 300D Turbo 165K. Totaled. Donor Engine. It runs!!!
1980 300SD 311K My New Baby.
1979 BMW 633csi 62K+++? Dead odo

You got 4° in the first photo and 2° in the second photo. Both are quite acceptable. I wouldn't bother with any keys at this point. And, how do you keep that engine so clean????

Being in Texas helps, but still man mines not even that nice.

__________________
Adam Lumsden
(83) 300D
Vice-President of the MBCA International Stars Section

I'm with Seth. That is one nice looking engine from what we can see. I like that!
Stretch (or elongation for our more anal members ) looks really good. You will have a few chime in on the accuracy of the marks vs the valve lift method, but it is still pretty accurate, and you are well within acceptable range.

__________________
Jimmy L.
'05 Acura TL 6MT
2001 ML430 My Spare

Gone:
'95 E300 188K "Batmobile" Texas Unfriendly Black
'85 300TD 235K "The Wagon" Texas Friendly White
'80 240D 154K "China" Scar engine installed
'81 300TD 240K "Smash"
'80 240D 230K "The Squash"
'81 240D 293K"Scar" Rear ended harder than Elton John

Had my valve cover pulled to check the rails. The tech and I looked at each other and laughed. 87,000 miles and no varnish or disdoloration at all!! The cam looked like it had never run. This car has had Mobil 1 since day one. I'd never use anything else.

John

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President Minuteman Section MBCA
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Those notches have to be exactly on the mark. The slightest difference will throw your reading off. That's why you got 2 different readings.

Maybe this is why the 2mm valve lift method is recommended? No room for error there.

You definitely don't need another chain but you can bring it back to spec with a woodruff key:
http://catalog.eautopartscatalog.com/mercedesshop/sophio/wizard.jsp?partner=mercedesshop&clientid=catalog.mercedesshop&baseurl=http://catalog.peachparts.com/&cookieid=1KP0H7YR81PU0J9ASO&year=1984&make=MB&model=300-SD-002&category=All&part=Camshaft+Woodruff+Key

It's a very simple job to bring your timing and injection pump back into line.

Danny

__________________
1984 300SD Turbo Diesel 150,000 miles

OBK member #23

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For the moment, let's assume that there are no c-clip master links available(at least I haven't been able to find any). Has anyone changed their timing chain without the c-clip master link? What was the method that you used? I'm guessing that if one considers how difficult the side plates are to get on and off, then one could probably run the chain through with just the side plate installed. I'm afraid that the pucker factor is extremely high for me using this method, though. If anyone can point me in the direction of finding one of these elusive c-clip master links, I would sure appreciate it.

Tom

__________________
1993 300TE
1984 300D
1984 300SD
1976 BMW R90S

This is correct. The width of the groove on the thrust washer can allow some serious errors if the mark on the tower is at one side of the groove for one measurement and on the opposite side of the groove for a second measurement.

Very nice pictures!

Can anyone explain the procedure for checking the chain? I see the valve cover is removed... which direction is the engine turned (forward then backwards?), I see the timing mark on the head, but where is it on the cam gear?

Thanks,
john

__________________
1986 190D, 2.5L, 5-speed swap, 180,000 Miles (60K by me).
Jeep CJ-7 with Cummins 4BT/NV4500/AtlastII 4.3.
Grand Wagoneer 4BT project in progress!

The way bodyart27 did it was to line up the timing marks. Look at the second picture. one mark is raised on the cam tower the other is indented in the cam washer.
You find the timing marks on the harmonic ballancer. it reads zero/zero then goes to 5, 10, 15, 20.
The 2mm valve lift method is described in the FSM:
http://skinnerbox.steaky.org/Service/W123/Index/617T/05Engine.htm
Select 05-215.

never crank the engine backwards!

Danny

__________________
1984 300SD Turbo Diesel 150,000 miles

OBK member #23

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what is with the two styles of chain from IWIS (JWIS?). one is all chrome pieces, the other has black internal links w/ chrome external links.

Besides chain stretch, is there a way determine if a chain has been replaced, or is new?

__________________

IIRC the factory chain doesn't have a master link. It's a continuous chain.

Sixto
87 300D

6 degrees of stretch is when you start to see smoke. advance your timing to compensate for the stretch.

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Have you ever noticed that anybody driving slower than you is an idiot, and anyone going faster than you is a maniac?

As long as they would add one additional commandment for you to keep thy religion to thyself.
George Carlin (Wonder where he is now..)

1981 240d (engine donor 1983 240d) recently rebuilt engine hurray! - No more.. fought a tree and the tree won.

pearl black 1983 240d 4speed (Converted!@$$%) atleast the tranny was rebuilt.