Mercedes Benz 280CE 1974mod M110 Bosch D-Jetronic

Hi,
I try to fix a Mercedes Benz 280ce 1974mod with M110 engine and Bosch D-Jetronic that not run so good, I try to go true everything to see if I can find the problem.

Now i have come to the ignition system, is here someone that know what ignition timing, dwell, ignition breaker gap and sparkplug gap that it shall be on this engine? It have transistor ignition.

I now use ngk bp6es with 0,8mm gap, ignition timing 10° btdc with vacuum disconected, dwell 32° on idle with 0,3mm gap on ignition breaker, but i dont know if this is correct?

Mvh. Knut Åge

Hi Knut Åge,

[strike]you will find ignition timing for you engine above in 107 workshop manual as it is the same engine M110.[/strike] Sorry, I forgot that M110 D-Jetronic is not there.

Okay here is the data for M110 Europe version:

• Dwell 34-40° in idle, not changing more than 3° in other rpm
• idle-run with vacuum: TDC +/- 2°
• 1500/min without vacuum: 14 - 19°
• 3000/min without vacuum: 32°
• vaccum retard in idle-run: 8-12°

Thank you, you know what can be wrong if dwell angel going down more than 3° on higher rpm? This going down to ca. 25° on higher rpm.

And you know the spark plug gap? Is 0,8mm ok?

Mvh. Knut Åge

Hi,

sounds like your bushings are worn and shaft dances a bit or the spring that closes contact is worn out. I always use 0.7 mm gap an my car's spark plugs.

Hi Knut,
try to adjust the points to the correct value first and clean (polish) the contact plates of the points.
Dirty contacts can lead to changes in the dwell values, too.

Just to make sure the bushings are really worn.

Regards
Norbert

Hi,

Have now checked more and see that the shaft in the distributer can move litle and I dont know if trancistor ignition box is in good condition, so we now order a new 123 ignition distributer and New red Bosch coil and see if things will be better. I have good experience with 123 ignition distributer on Volvo 164E with D-Jetronic.

Thank you both for help

Mvh. Knut Åge