somethings not right 912ul
in 912 / 914 Technical Questions
6 years ago
I'm at my wits end trying to sort out my older 912ul. I'd love to turn it over to Rotax mechanic but there are none in my area. Here's the problem(s) It starts and runs OK but It has a miss, feels like a vibration at higher RPM. Miss is worse at around 2500-3000 rpm. The ignition drop is 150-200 at 2500 rpm on both A & B system. It is definitely worse on the B module. I've switched the charging wire (red one) from the A to B box. B box still runs worse. I've replace the ignition leads to the plugs, plugs, the spark plug boots, checked all the wiring. I'm starting to think it's in the B ignition coils or ground. How can I check for sure ?
So just when I'm thinking its an ignition problem add this to the mixture. It runs really rough between 2000-3000rpm unless the idle mixture screws are only 1/2 to 3/4 a turn from completely closed. The manual says they should be 11/2 to 13/4 turns out. Is it trying to tell me something? I've had the carbs rebuilt twice, new rubber connectors, floats, needles etc. and have synced it several times with both a CarbMate, and vacuum gauges.
So I don't know if I have one problem or two. I'd appreciate any thoughts or if someone could recommend a Rotax mechanic in the Charlotte NC area.
Thanks
Skip
So just when I'm thinking its an ignition problem add this to the mixture. It runs really rough between 2000-3000rpm unless the idle mixture screws are only 1/2 to 3/4 a turn from completely closed. The manual says they should be 11/2 to 13/4 turns out. Is it trying to tell me something? I've had the carbs rebuilt twice, new rubber connectors, floats, needles etc. and have synced it several times with both a CarbMate, and vacuum gauges.
So I don't know if I have one problem or two. I'd appreciate any thoughts or if someone could recommend a Rotax mechanic in the Charlotte NC area.
Thanks
Skip
