Don't think the new MBs can take the load of the 240 fenders :)

Yes, I understood the prevous post.

Tom W

As stated above I understood the previous posts which said you would have to change heads and pistons along with the other stuff.

And at that point it would be cheaper to replace the entire engine.

But it still seems to me a lot could be done with just a modern injection system installed on our ancient 616 or 617 engines, without changing the heads and pistons.

Tom W

I am pretty sure the Gurkha set up with the OM616 has nothing really elecronic in it.

A retrofit on the block and IDI head could be electro-mechanic. Timing is determinate by a wheel attached to the port of the pump. and in the same fashion than a distributor cap it sends directly a pulse to an electric injector on a common rail.
I am convinced this would not be a particularly hard set up to come about. No ECU just mechanical brute force like gasoline engine of long gone times...

There also a concept like this about valves control...

Absolutely correct, the Gurkha up to Euro-II was all mechanical affair, but with Euro-III and IV, it became electronic to meet up with the stringent requirments.

Yep...it's probably easier to weld motor mounts for a 220CDI EURO spec motor and tranny then to mess around with a 240D!

The problem is that all the modern injectors, etc are all DI. So about the only way to get a common rail type system on our old benzes is to find some kind of valve that will open/close the fuel rail pressure to our stock nozzles. Those don't exist that I know of because all the modern injectors are injector and valve combos (and we can't use those nozzles since they are DI). If you could find some kind of electrical actuator that can operate at 150bar with the precise timing of microseconds then the project is doable... until then the parts just aren't there to do it. :(

I am pretty sure anything using the old mecanical injectors would not be fast enough to respond to the very fast electical signals used by the new systems.

Tom W

True. The modern piezo injectors are able to do five (last I heard, probably up to 6 or 7 by now) injection events per combustion cycle. Ours do one. Another thing is that the injection pressure in our systems is an order of magnitude lower than what the modern systems are doing. The higher injection pressure and resulting better atomization are some of the main reasons for the increased combustion efficiency and reduced smoke of the modern systems.

On edit: This discussion is making me want to get another engineering job.

while less "fun" this thread got me thinking when I walked past a few 180 and 200 CDI's (A and B class)

CDI motors do show up on ebay over here and not too expensive..didn't even bother reading to see if they actually run..the smaller ones a probably more likely to fit..though that may be an incorrect assumption.

this one

says if you need other parts (e.g. the computer stuff) that you just have to ask.