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Electronics International FT-60 red cube failure?

Hello, How many of you have experienced a failure of the red fuel cube? Yesterday my GPH was reading zero. Also my fuel electronic fuel gage showed I was burning more fuel than actual and to top it all off my oil pressure which usually runs about 58-60 psi was fluctuating to 66 psi and fuel pressure fluctuating between 2.8 and 5.4 psi in level flight. I have gone through and checked grounds and connections and all seem fine. The plane had not been flown in over a month and the Dynon backup battery was at a very low charge where when starting the aircraft it froze up with a white screen with a line vertically through it and I had to do a hard reboot pressing buttons 1,2 and 5. So still not sure if it's the fuel cube that failed or something else with all the odd readings. Any thoughts? Thank You:confused:
 
I am on my second Red Cube but before I replaced I messed with it a lot. I took it out and checked for obstruction, nothing. Ran some air through it to see if the impeller moved and it appeared to be okay. Reinstalled but still not working.

Called support at Vans and they told me to blow through it and it will make a sound like a kazoo. So off it came, no kazoo sound, and I ordered a new one. I tried the kazoo test and it made that annoying “music.” Now I knew what I should hear and see with a functional Red Cube.
 
I have a Flow-Scan version - -

I have posted this before, but I called the company and they told me how to help it out. Fill it half full of carb cleaner and shake it wildly. Do that a couple times. This worked well on two occasions. I then experimented on my own. After 2 times with carb cleaner, the third time I put WD-40 in and shook it a bunch. That was 2-3 years ago. Has worked perfectly since then. A cheap try if you don't mind a little work.
 
The fuel flow from my 10 year-old FT-60 has been working fine until a few months ago, but now about 80% of the time it works OK, but the rest of the time it intermittently and randomly reads zero (on AFS 5400 EFIS). I have a new Red Cube on the bench as well as a couple of new fuel and oil pressure sensors to address the Kavlico-related service advisory that AFS (and Garmin and Dynon) sent out, but haven't gotten around to replacing those three things yet. I have an oil/filter/plug change coming up in a few tach hours and while the cowl is off, I plan to get my A&P to address replacing the FT-60 and those sensors at the same time.
 
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My first red cube exhibited the weirdest failure mode... Remember, it's essentially a pulse generator. For a couple of months it started reading somewhat backwards. Lean in flight and the fuel flow would to UP. Enrichen the mixture and the fuel flow would go DOWN. Very weird. At the end of the flight the total fuel burn was still reasonably accurate, within 10%, which I found astonishing.

Before long I started seeing fuel flow substantially below expected. Over the span of a half dozen flights it went from being just a little low (maybe 1GPH) to being less than half the expected flow. Then I started to see drop-outs to 0GPH.

I had a couple of spares on hand so replaced the sensor completely. Yes, I could have tried the carb cleaner trick, but, in honesty, I was pressed for time and I needed accurate fuel flow for an upcoming trip. Outright replacement was the easiest and fastest path (no, I didn't throw out the old one!).

After the new sensor was installed I expected I would have had to mess around a fair bit with calibration. Nope, it was within 2% right out of the box. I made one little tweak to the K-factor and now it's as close as any reasonable pilot would hope for - less than half a gallon in 30 gallons. This airplane requires one to "burp" the tanks to get maximum fuel on board so it's quite possible the error I'm seeing on the flowmeter is purely a function of my inability to get an exactly consistent fill on the tanks.

Accurate fuel flow data is a wonderful thing to have in the cockpit!
 
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