240D timing adjustment problem..
 

Looks like the source of my idle issues has surfaced. Its timing. I decided to fool with it a bit since I kept getting a reading of 12 degrees BTDC. When I loosened it up I noticed its already at the limit of the sloted holes and i cant rotate it anymore to adjust the timing. So, that tells me the pump is out of wack. My first question is, can this happen as a result of chain wear or some other natural cause? Or is it a result of Bubba Benz working his back yard magic at some point with a pump installation? My second question is how do I go about fixing it in the easiest manner?

I think you are one chain link off on your pump sprocket. I think that is 18 degrees but not positive. Possibly occured when some past owner changed the chain out. Hopefully he did not pay a garage for a quality job. :rolleyes: The good thing is it should seem like a different car when you get it to 24 degrees btdc. Out of curiosity what are your idle issues? I have two 240ds as well. That car had to be slow. Not sure if you can work enough slack into the system to move a tooth. Others will know as that error is not uncommon.

Car has great highway power, and smooth as silk in idle out of gear. As soon as it goes into gear the whole car vibrates and shakes. I can hold the go pedal down a bit and smooth it out but in 700RPM idle in gear it will vibrate your fillings out. No black smoke, even on hard accel which seems odd and in gear when hot it smokes black/grey in gear in idle. Already replaced motor mounts, injectors, filters, etc. As a side note that may or may not be related, I cant get a normal reading for chain stretch by using the cam tower notch method. When those notches are dead on the stretch is like 20 something ont he banacer ring and I know it cant be that high. Ideas?

You are not supposed to use the cam tower marks for that...only when assembling the engine ..
You use the 2mm movement of the number one intake valve. Lots of threads about how to do this....

You have IP timing that is off by 12 degrees.........late.

With the tower marks, you have cam timing that is off by 20 degrees........late.

Something is definitely amiss with regard to the chain. It appears that the chain was replaced and both the camshaft and IP are off by one tooth.

As Greg mentioned, check the cam timing properly using the 2mm valve lift method........then you'll know for sure what you have.

The more information helps. I was questioning details of the idle performance as I thought 12 btdc on the pump would not cause idle problems. Just poorer than possible power and lower fuel milage. My suspicion is that under light loading that cam setting might be giving the problem. It may also answer why your high speed is not bad. Of course it accounts for your unusual smoking. But overall besides being well outside factory design it is not a good situation obviously. Do get the pump and cam timing sorted out first. If any problems remain then tackle them. Spend some time in the archives to decide how you are going to approach it. I would not bother to use a dial indicator to check the chain stretch until the chain sprockets were corrected. Unless you want to do the math for the one tooth out. I only think it is 18 degrees.

With so many potential things being off where do I start? How do i reset everything to spec and start over? It doesnt seem I have any trustworthy references to use as a baseline. Rip out the chain and remove the pump? I dont have the tools to press in a new chain link so I wanna make sure Im resetting everything as easily as possible.

The first thing to do is to check the camshaft timing via the 2mm valve lift method. There is a very good procedure in the DIY section written by Danny which will show you how to do this.

If you confirm that the cam is late by about 18 degrees, you need to advance the cam, relative to the crankshaft, by one tooth. This is not difficult to do, but, you must be careful not to lose any hardware down the chain gallery and you must suspend the chain from overhead to prevent loss of the chain around the crankshaft sprocket.

If you advance the camshaft and reinstall the cam sprocket, make sure you rotate the engine by hand with a socket wrench to be absolutely sure that you have rotation and the valves don't hit the pistons.

Once the camshaft is close to spec, then we deal with the IP timing.

When Barry said this :

" I would not bother to use a dial indicator to check the chain stretch until the chain sprockets were corrected."

He was not visualizing the fact that checking this will show you if your cam sprocket timing is way off... he was just thinking about the chain itself..

In other words... LISTEN to BRIAN....

I was asked via PM to post the specs of my car. Its a stock 240D with 130k miles on it. Good compression. Now with a seemingly mistimed Cam as well as this injection pump issue.