What's new
Van's Air Force

Don't miss anything! Register now for full access to the definitive RV support community.

Very low and erratic FF on G3X Touch

Haines

Member
I have a G3X touch in an RV7A with a Lycoming YIO360A1B6 200 hp. After not flying for a couple weeks I took off and shortly after noticed FF readings moving erratically from 8.5 or 9 GPH to 0.8 GPH while in a steady 1200 FPM climb and no change in engine power. Fuel transducer? Sensor? Wiring? Thanks for any help.
 
More likely the sensor. I've seen this on a couple. If engine mounted the vibration is hard on them. Currently have mine mounted on the engine mount to reduce vibration and Temperature exposure.

Dirt can cause problems as well.
 
FF issues

Flew again today and FF on G3X went to 0 you shortly after startup. Still transducer problem ?
 
Check your connections back to the engine module. If they are good my guess is the sensor.
Dirt can cause the same problem. Not sure how to clean, I wouldn't use compressed air, you could try blowing air or running fuel reverse through it and see if anything comes out. Hold it over a cup with a paper town to strain the fuel.

The first -8 I built the next owner reported the same thing. FF was erratic for about a month, then went to zero. The sensor (red qube) was engine mounted. I replaced it, adelled to the engine mount and has worked since. I noticed on the old unit the vibration sleeve on the wires was broke free, and figured the direct engine mounting was the cause. I know others have reported the internal flow sensor gets excessive wear from vibration. I am assuming yours is engine mounted. If so I recommend moving it.
 
Back
Top