Continuing my long tradition of self diagnosis and replacement of the perfectly functioning parts on my '78 300D I have now replaced the timing chain, tensioner and upper guide (it ran fine but needed it after 212K).

Now it turns over but will not start. During the feed-through I did not main adequate tension on the old chain and got bound up - eventually fed it through but wound up with the upper cam marks way out of alignment so removed and rotated/jumped teeth on upper cam to get crankshaft TDC and upper cam marks back in synch. I am almost positive this process resulted in shifting the Injection Pump cam so it is no longer at the correct start of delivery. I am about to open it all back up and do a drip test (which I have found the thread for thankyouallverymuch) - finally my actual question;

If I find that the IP timing is off how do I rotate the cam or "jump teeth while maintining the crankshaft/upper cam timing... My backyard mechanic freinds have a theory but I'd rather not add to the problem if it will ultimately need to be fixed by a professional.

I performed valve adjustment (and re-checked), the upper and lower timing marks align, all glow plugs are good/checked out.

My instinct is to tow it to a professional (who will clean up my mess for a small fortune) and go back to woodworking. Sorry for long-winded-ness - first time poster/long time auto-wrecker/part replacer.

set the crankshaft mark on 24 deg BTDC.
Take out the IP. Turn the cam of the IP to match the marks on the IP and put the IP in. Take care that the 3 fixing bolts are about in the middle of the flange wholes. Do the fine adjustment with drip method.

Tom

Woodworking is so much more enjoyable than trying to figure these car's instruction out...
I am about to get my free 18 inch Craigslist bandsaw going and install one of my routers in a table.... of course I am trying to figure out what I can make out of mesquite FOR my Mercedes.... we are a warped group of individuals...
I really think you need pictures of what Tom described before you go farther... At least the CD of the FSM... or a paper copy would be nicer... it is possible to damage things by not knowing precautions to take... or make it more expensive to get a pro to get you back to the starting point...
Have you looked locally at part's houses for the Haynes manual ? 10 bucks or so would sure help... it has better pictures in many instances than the FSM... so I usually use both when tackling sensitive things... but Haynes leaves OFF many warnings which the FSM has in it....
It may be as simple as Tom described... but I would investigate more before taking it apart... sometimes little warnings like ' make sure some part does not fall out ' or ' note the relationship of 'x' before taking the next item off' .... if not known can ruin your day...

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1980 240d ,

chain elongation, cam marks reference:
http://www.peachparts.com/shopforum/diesel-discussion/10414-help-i-need-check-stretch.html

http://www.peachparts.com/shopforum/diesel-discussion/305365-9-degrees-chain-stretch.html

evap fin cleaning:

http://www.peachparts.com/shopforum/diesel-discussion/156207-photo-step-step-post-showing-w123-evaporator-removal-1983-240d-1982-300td.html?highlight=evaporator

A/C thread

http://www.peachparts.com/shopforum/diesel-discussion/297462-c-recommendations-mb-vehicles.html

I have no idea of how to fix this, but I surely can relate to your overall situation. How many times have I put myself in a similar situation. This forum is a Godsend.

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John Schroader
bio burnin' 83 300D, '83 300 SD, '79 240D
"I've never met a man who was good at making excuses who was good at anything else" Ben Franklin
"You cannot permanently help a man by doing for him what he could and should do for himself" Abraham Lincoln

Welcome to the forum.

Let's stop right there. Please describe your process in detail. If the chain never came off the IP timer and crankshaft, it's unlikely that the IP timing is off by more than 10 degrees.

A significant error in the IP timing can occur only if the chain is disengaged from either the IP timer or the crankshaft during the process.

Furthermore, the engine will usually start if the IP timing is off..........it will just run badly.

Heres the drill...get the cam and crank marks lined up, the chain can be 'bunched up" and moved to accomplish this. Then pull the IP and turn the engine to the 24 degree mark, (heres where, I and others have screwed up) The 24 degree mark MUST be on the compression stroke. (#1 cam lobes more or less UP). Install the IP on its mark. You can do this. It should start, as mentioned above, the timing should be close enough, then you can time it to get it right on the money. Good Luck

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1985 Euro 240D 5 spd 140K
1979 240D 5 spd, 40K on engine rebuild
1994 Dodge/Cummins, 5 spd, 121K
1964 Allice Chalmers D15 tractor
2014 Kubota L3800 tractor
1964 VW bug

"Lifes too short to drive a boring car"

Thanks Brian- I had an assistant secure the in-feed while I pulled on the old chain and advanced the crankshaft via socket. About half-way the chain boound up and after backing the other way (now counterclockwise) we realized I had not been pulling hard enough on the emerging chain and in releasing the pressure there was enough sag in the chain that it was no longer engaged with the crankshaft. (Of course most of this was slowly theorized after we'd pulled it the rest of the way through and found that the top cam and cranshaft TDC marks where off - so we removed the top cam and rotated cranshaft/jumped upper cam teeth until we got back to both marks aligned and then could smoothly cyle through a full revolution . SO I pretty much know that there was a time while hung up that I both advanced and reversed the crankshaft independently of both the upper cam AND the IP cam.

You can take the chain and drop it down into the abyss............fish it back out...........and you won't lose the engagement on the crankshaft. So, that's not your problem. If the chain maintained contact with the IP timer and the crankshaft, you can't lose IP timing. Only if the chain came completely out of the engine at some point will those two be out with respect to each other.

The chain might have bunched up and pinched itself on the way out, but the wrap around the crank sprocket was not affected by this action.

Steve -

Whats really cooking my noodle is that if the IP cam has a woodruff key (one diagram I've seen indicates it does) then how will I be able to re-connect the IP when the cranhsft is rotated to 24BTDC? It only goes on one way right so once I remove the IP and rotate to 24BTDC the ip cam will have rotated also. I have a coworker bringing me their Haines tomorrow. Hopefully a front end view of the timing chain circuit will help me think this through/speak more intelligently.

Brian sory I wasn't realizing you were realtime so I am jumping between comments and acting like a tard.

So should I start with a drip-test to confirm that the timing is not off?

On the drive end of the IP has a externally Splined Collar; that is the part that the woodruff key is keyed into. The Splined Collar fits/slides into the rear of the IP Timer that is driven by the Timing Chain (the hole is also splined to match the IP drive).
Unfortunately it can be slide into any of 32-33 positions (I do not remember how how many splined teeth there are).

In the first diagram at the below site #227 is what I am calling the Splined Collar. If you look to the right at the IP it is shown with the Collar assembled to it.
http://www.detali.ru/cat/oem_mb2.asp?TP=1&F=123130&M=617%2E912&GA=722%2E118405&GM=716%2E005++++++++++++++717%2E400&CT=M&cat=143&SID=07&SGR=045&SGN=01

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84 300D, 82 Volvo 244Gl Diesel

That would definitely be recommended. However, the procedure isn't the easiest to understand or master for a fellow who's not done it before. Also, if the timing is way off, the procedure tells you nothing. But, it also tells you nothing if you fail to execute the procedure properly.

I have never used the "woodruff key" so I'm no help there. When ever I get involved in pulling a cam or anything that involves "possibility" losing timing, I do, (or suspect I have) ... and the only way I know all is well is to do what I described above. That involves learning to time your IP.

Who knows you may be luckier than I and your IP will be spot on.

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1985 Euro 240D 5 spd 140K
1979 240D 5 spd, 40K on engine rebuild
1994 Dodge/Cummins, 5 spd, 121K
1964 Allice Chalmers D15 tractor
2014 Kubota L3800 tractor
1964 VW bug

"Lifes too short to drive a boring car"

Brian - I feel like I have accurately followed the IP Start of delivery procedure (Drip tube) as described in the Haines manual. But with what you've said I am questioning results. I consistently get 2 second inteval drips (supposed to be 1 sec) but this doesn't happen till I've rotated the crankshaft all the way through from 24BTDC to TDC then at 45 BTDC I get drip action that ends by the time I get back to 24btdc...

Or does it really not work like that - if I hand crank through multiple cycles I should start to have drips @ 24BTDC right?

ahh - very helpful thanks - I wasn't understanding where the woodruf key is now I understand its inside on the intermidiate shaft and not part of the splined connection.... so the potential IP removal/realignment makes sense... not that I think I do.