.png)
Ignition miss? above 5100rpm
in 912 / 914 Technical Questions
12 years ago
I don't like starting a new thread if it's redundant but I've searched the forum for this topic and not seen it. I've a 912ULS with 440 hours on it. Until recently I never got over 4800 rpm. After calibrating my tach (OK) and checking linkage for full throttle I increased the pitch on my prop from 14 degrees to 16.5 and the rpm at WOT increased by approximately 300rpm. That's the good news. The bad news is that when I run at WOT for any length of time I notice a very slight miss or stumble as if one plug was mifiring. If I back off WOT to 4800rpm, the miss goes away. Since I recently changed plugs I pulled them and inspected as well as checked the gap and checked ignition wire attachment but found nothing that appeared abnormal. The engine idles smoothly, temps are all in normal range and the engine is easy to start.
I overhauled both carburetors at 425hrs and did both the mechanical and pneumatic synch and changed the fuel filter. I need some ideas on where to go from here.
I overhauled both carburetors at 425hrs and did both the mechanical and pneumatic synch and changed the fuel filter. I need some ideas on where to go from here.
