OK. So I finally checked the timing chain stretch on the 81 240 today.

Using the 2mm method with a dial indicator it appears I have about 4 degrees. I know the car has about 160k mile son it so this does not seem realistic. I'm assuming either the chain has been replaced or there has been an offset key installed at some point. I have no service records for this vehicle and it was a rusty beater when I bought it. But I figure 4 degrees is not bad.

So I go to set the timing using the drip tube method. Set the balancer to 24 degrees BTD. Using all the available travel in the pump I can not get the spout to slow to 1 drop per second. So does this mean I will need to reset the injection pump or do I need to compensate for the 4degrees off my timing chain is? I know I'm going to have to pull the cam sprocket to check for an offset key just t get an assessment on the chain BUT in the interest of getting it to quit smoking with new rebuilt injectors will compensating for the current stretch get me in the ball park? (without having to tear off the IP?)

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1978 Mercedes 240D
1981 Mercedes 240D
1982 Mercedes 240D

I am not sure what you mean. Do you think you should have more stretch or; or do you think you should have less stretch.
In the Manual it gave a figure for a used chain after X amount of Miles. How, does your reading compare with that.

There is a chart in the Manual that has which Offset Woodruff Key to use for which amount of Degrees to correct the Camshaft Timing. If you installed the Offset Woodruff Key properly that would return some of your Fuel Injection Pump Timing back closer to normal.

However, Your comment about the Fuel Injection Pump not being able to turn further in the slots makes Me think that that someone has had the Fuel Injection Pump out before and did not install it with the Studs in the center of the Slots on the Flange.

Also have You done the Drip Timing before? I ask this because it is very easy to go rotate the IP past the tiny sweet spot.

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84 300D, 82 Volvo 244Gl Diesel

That makes two of us.

A better description of the current state of affairs is required.

OK so I have the balancer set at 24 degrees before TDC. I just pulled the injection pump. Oddly the timing marks on the IP are totally opposite of each other?

I've done drip timing before, no problem. ON the 82. I would think the marks on the pump housing and the pump gear need to line up or be somewhat close if if the timing is right and the balancer reads 24-25 before TDC.

I'm going to try to line up the pump timing marks, re install it and try the drip timing again to see if it's close to right now.

By the other stuff I meant I had no idea if the chain had been replaced. it has 160k miles. I have no records. I assume based on the condition I got it in it was abused. I was trying to measure stretch to see what condition the chain was in. at 2mm lift on the #1 intake valve measured using a dial indicator the reading at the balancer was about 4 degrees off what the FSM said it should be as new. So to me I figure there is either a offset key installed at some point to adjust the timing or somebody replaced the chain. Basically I have no idea till I pull the cam apart and look for the key right?

I only asked about adjusting for the timing offset because I had no idea if it figures into the timing adjustment on the pump. So ifsay if you know your chain is 4 degrees off and you know you aren;t going to put a new chain or other key in to get it perfect, does that affect the degree measurement you want the balancer disc to read at the start of delivery by 4 degrees?

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1978 Mercedes 240D
1981 Mercedes 240D
1982 Mercedes 240D

Just to make sure 100% I'm doing this right the 24degree mark is the one BEFORE the 0 degree T mark right? Not the one after... as in the 24 degree mark clockwise on the balancer from 0, not counterclockwise...

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1978 Mercedes 240D
1981 Mercedes 240D
1982 Mercedes 240D

It also needs to coming up on the Compression Stroke.

You still did not say if you thought the 4 degrees you got was too much or too little for the miles on your Engine.

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84 300D, 82 Volvo 244Gl Diesel

Too little. I would think for that many miles!

I'f I'm wrong please tell me what it should be...

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1978 Mercedes 240D
1981 Mercedes 240D
1982 Mercedes 240D

OK I feel like an idiot now. I'm not sure what planet I was on but for some reason I was assuming 1:1 correlation in number of revolutions on the crank to the cam. DUH.

This may explain why the IP timing was off by exactly 180 degrees based on the marks on the IP pump shaft...

See this is what I get for assuming I know instead of RTFM.

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1978 Mercedes 240D
1981 Mercedes 240D
1982 Mercedes 240D

See pics

Attached Thumbnails

   

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84 300D, 82 Volvo 244Gl Diesel

I am trying to understand this.
If you did the 2mm Method correctly you would end up with a degree Reading and the Manual has "At this position, the reading on the Balance plate should agree with the specifications "Intake Valve Opens".

From the Chart a 616.912 with a new Timing Chain would show 9 degrees and a used Timing Chain with 20,000 Km on it would show 11 degrees.
This means that a used Timing Chain with "about 160k mile son it"would likely show more than 11 degrees.

If after you do the procedure you are showing 4 degrees on the Damper where the Pointer points to there is an error on how the procedure was done or some other mechanical problem (like someone installed a Offset Woodruff Key backwards).

If you are saying that you got 4 degrees over the 9 degrees that a new Timing Chain would have you would be seeing 13 degrees on the crank Shaft.

Attached Thumbnails

 

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84 300D, 82 Volvo 244Gl Diesel

Now I'm really confused and not convinced at all I'm doing this right. Ok I need to step back and make sure I'm doing this correctly. Is there a thread on the correct way to do the 2mm lift check?

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1978 Mercedes 240D
1981 Mercedes 240D
1982 Mercedes 240D

ok. I printed the instructions from FSM. I read this inside, then went outside and tried to do this from memory. bad mistake. For starters I did not remove the lash. At this point between goofing the compression stroke and this I'm going to start fresh in the AM and work precisely from the printed manual pages. Thanks for straightening me out guys! I'm 100 % certain that I am just not doing this correctly.

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1978 Mercedes 240D
1981 Mercedes 240D
1982 Mercedes 240D

This might help too

PeachPartsWiki: Measuring Timing Chain Stretch

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1992 W201 190E 1.8 171,000 km - Daily driver
1981 W123 300D ~ 100,000 miles / 160,000 km - project car stripped to the bone
1965 Land Rover Series 2a Station Wagon CIS recovery therapy!
1961 Volvo PV544 Bare metal rat rod-ish thing

I'm here to chat about cars and to help others - I'm not here "to always be right" like an internet warrior



Don't leave that there - I'll take it to bits!

I'm going to print this and take it out too.

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1978 Mercedes 240D
1981 Mercedes 240D
1982 Mercedes 240D

Woo hoo! Got the timing perfected today. It runs like a whole other car now! It accelerates when I step on the pedal and much less smoke! Of course once I move the AC over from the 1982 it will probably slow down again. LOL

I'll change the oil and run two cans of diesel purge through it next weekend and I think I may be about ready to go get it inspected. I'm excited to almost have a daily driver again!

It still needs a lot of work. Paint, (It's like 5 different colors on the various doors, hoods, sunroof, etc.) and a front suspension rebuild. But it's coming along...

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1978 Mercedes 240D
1981 Mercedes 240D
1982 Mercedes 240D