Red Cube FF drop outs to zero flow...

[schristo@mac.com]

My fuel flow indication from a red cube transducer to a Skyview system have just started to intermittently display a zero flow drop out. No fluctuation of the flow is observed, just an apparent complete loss of signal to zero for several minutes then back to normal.

Any similar experience or troubleshooting thoughts?

[miyu1975]

Have not seen this on mine..., assuming your engine didn't die when FF went to 0. I guess I would start with the wiring checking for loose ends, bad crimp..etc.

[schristo@mac.com]

Originally Posted by miyu1975

Have not seen this on mine..., assuming your engine didn't die when FF went to 0. I guess I would start with the wiring checking for loose ends, bad crimp..etc.

Thanks Ryan, no engine fluctuation or erratic indications typical of a connection issue... I suspect that it is a transducer failure within the red cube but will trace the wire and connection side of things.

[Brantel]

Had a similar failure.

It was the factory crimped connection.

[schristo@mac.com]

Originally Posted by Brantel

Had a similar failure.

It was the factory crimped connection.

Thanks Brantel, do you recall which wire you found the failure on? I replaced all of the factory ends with d-sub pins and wrapped them with heat-shrink...

Electrically, I am seeing no jump or erratic signal... simply a removal of the signal voltage to 0.0 indicated for several minutes then a return to normal function.

You did not see any erratic fluctuation in the signal or flow?

[Brantel]

Mine was in the signal wire. It was reading all over the place then it just stopped.

The wire was still in the connector but the wire inside the insulation was broken.

[pvalovich]

I had an issue with random fluctuating fuel flow indication (no change in engine performance). Called EIS and was told to crimp the h*ll out of the conectors. Used long nosed pliers and a lot of force on all three wires. Problem solved - although I still don't know which lead was the culprit.

[schristo@mac.com]

Originally Posted by pvalovich

I had an issue with random fluctuating fuel flow indication (no change in engine performance). Called EIS and was told to crimp the h*ll out of the conectors. Used long nosed pliers and a lot of force on all three wires. Problem solved - although I still don't know which lead was the culprit.

Thanks pvalovich, as it turns out, I am not seeing a fluctuating or erratic reading... it is normal and regular with expected stability and function and without any power change or other flight change of any kind the signal will drop to zero volts and the indicated fuel flow will drop to zero.. a few minutes later normal function returns.

I inspected the connections and crimps and they do not appear to be the source of the observed loss of signal voltage

[dmaib]

Is your EIS Grand Rapids? If so, it might well be the transducer. I've had to replace one or two fuel pressure and oil pressure transducers in 5 1/2 years. Symptoms sound identical.

[BSwayze]

Stephen, I'm curious about how you installed it. I don't recall seeing a photo of where/how you mounted it. Is it on the engine, the firewall, or inside the cabin somewhere? I finished mounting mine on the firewall a while back, after much deliberation and research. I'm curious if this may have anything to do with it.