914 stalls above idle

Ken,

Yes, the carbs were rebuilt as part of a 5-year rubber replacement when the engine was being moved from the damaged fuselage to the new one.  With special attention paid to the torque of the float bowl hold down bolts.  I'm going to continue to concentrate on the troubleshooting on the fuel system.  A lot of work has been done to this poor Kitfox all at the same time opening up the possibilities of Maintenance Induced Failures (MIF) as Mike Busch would say.    

Bill,

I agree with the diagnosis of fuel starvation.  At the time I moved the engine from the damaged fuselage to the new one I also completed a 5-year rubber replacement.  So all the fuel lines and filters have been replaced and the carbs rebuilt.  That doesn't mean a blockage wasn't introduced during the time the fuel system was opened up like that.  More testing... 

Jim,

Agreed, but that is why I'm looking for other ideas.  The fuel pump pressures are good, fuel lines and filters replaced, as well as the carbs rebuilt during the 5-year rubber replacement IAW Rotax manuals and applicable service bulletins.  Testing goes on... 

Jeffrey,

At the inlet side of the electric fuel pump there is a very small rounded shape fine filter. It inside the fuel intake at each pump. Check if that is partially clogged from debris as it can still show adequate pressure but not enough flow (quantity) for higher rpms.  It’s a bit tricky to remove them from the pumps but I believe that it good to eliminate this possibility as well. 

Spiros,

Thank you again.  Fuel starvation seems to be this engine's issue.  During the 5-year rubber replacement, all the fuel filters were replaced but I was unaware of these fuel pump inlet screens.  I will certainly check them.  

I try in life to learn some new every day.  Today I learned more about the fuel system of the Rotax 914.  

Jeffrey