Engine runs rough on one line

Hi Konrad,

Is this a problem that manifests at start up ie when engine still relativly cool (oil below 50C) or is is during pre-flight run-up checks when engine warm (oil above 50C)?😈

Hi Konrad,

I've experienced these problems before where the evidence would suggest that the fault lies with the ignition. However, my experience is that the fault often lies with the carbs due to the poor atomisation of the fuel and this manifests itself as uneven ignition drops. Even if the carbs have been serviced, it is still possible to have blockages in the smaller passages and drillings in the venturi. I have had this happen myself.

Hi Sean,

i only checked it in warm conditions (Oil above 50) - i will try it within the next days in colder conditions 

Thank you

Hi kevin,

Thanks a lot for the heads up. I’ll check those as well next time if I’m at the airfield.

Hello everyone,
I wanted to give you an update on what I've been doing and how things are progressing.

Firstly, I replaced the spark plugs with new Rotax ones, but there was no change. Then, I replaced a suspicious-looking spark plug connector and shortened the ignition cable slightly to ensure the stranded wire was fresh and the spark plug connector could be screwed in tightly. – still no success.

Next, I checked all the plug connections on the ignition boxes and replaced the boxes – still no change.

Now I'm back to square one. I was also told that there is probably a fault with the radio at low rpm, which causes a humming sound. Could that be a clue to the problem? Where else can I look?

Thanks!