Fixing a Faulty fuel flow sender FT-60 Red Cube
Hi Guys,
My FT-60 has been failing for the last two weeks, total installed and flying time 630 hours, initially it started not providing an output to my Skyview display and I though that I must have had a bad crimp connection, so I checked this by re-crimping the the 3 wires that connect the FT-60 to the Skyview. Went for a fly and all seemed good, the next week while flying it again failed, so having ensured that the wiring was OK the next culprit was the FT-60.
I removed the FT-60 from my RV7 and opened the access cover to the side with the control board, he screws are held in place with thread lock but came out easily enough,
The board is covered with some rubber sealant which I was easily able to remove with a jewelers screw driver.
This revealed the circuit board and it was immediately apparent what the problem was, the chip that is sitting on the edge of the FT-60 in the photo was loose, when I pressed down on it, it came away from the board.
I do not have the tools to work in a confined space such as this so I pretty much gave up at this point and ordered a new unit.
By chance I sent this photo to Glen an RV friend of mine who immediately said I have a friend who can fix this.
Below is the email response from Glen to me this morning;
Hi Eddie, a quick visit to Ron was as educational as ever. When I described the part that fell off the board, he said, "Yep, that'll be a 2903 comparator. I'll just put a new one on."
So, lay the original on his flatbed scanner, scan at 4800 dpi and enlarge so he can read the lettering. Yep, that's what it is all right. In goes a new one. He uses flux from a syringe, and a fine iron rather than re-flow. While in there, he redid a couple of other dodgy joints.
Hook up some power, and look at the output on the scope. Blow through it, and lots of lovely square waves ensue. Score!
Rather than use potting compound, he sprayed it with a lacquer which will protect and secure it. All you need is some suitable gasket compound to seal under the hatch. It may not even need thread lock on the screws as they are a bit tight anyway. Also some form of gumbo around the wire where it enters, as you already spotted.
Awesome, thanks soooo much Glen and Ron.
I have cancelled my Spruce order and will re-install this Saturday.
Cheers
Hi Guys,
My FT-60 has been failing for the last two weeks, total installed and flying time 630 hours, initially it started not providing an output to my Skyview display and I though that I must have had a bad crimp connection, so I checked this by re-crimping the the 3 wires that connect the FT-60 to the Skyview. Went for a fly and all seemed good, the next week while flying it again failed, so having ensured that the wiring was OK the next culprit was the FT-60.
I removed the FT-60 from my RV7 and opened the access cover to the side with the control board, he screws are held in place with thread lock but came out easily enough,
The board is covered with some rubber sealant which I was easily able to remove with a jewelers screw driver.
This revealed the circuit board and it was immediately apparent what the problem was, the chip that is sitting on the edge of the FT-60 in the photo was loose, when I pressed down on it, it came away from the board.
I do not have the tools to work in a confined space such as this so I pretty much gave up at this point and ordered a new unit.
By chance I sent this photo to Glen an RV friend of mine who immediately said I have a friend who can fix this.
Below is the email response from Glen to me this morning;
Hi Eddie, a quick visit to Ron was as educational as ever. When I described the part that fell off the board, he said, "Yep, that'll be a 2903 comparator. I'll just put a new one on."
So, lay the original on his flatbed scanner, scan at 4800 dpi and enlarge so he can read the lettering. Yep, that's what it is all right. In goes a new one. He uses flux from a syringe, and a fine iron rather than re-flow. While in there, he redid a couple of other dodgy joints.
Hook up some power, and look at the output on the scope. Blow through it, and lots of lovely square waves ensue. Score!
Rather than use potting compound, he sprayed it with a lacquer which will protect and secure it. All you need is some suitable gasket compound to seal under the hatch. It may not even need thread lock on the screws as they are a bit tight anyway. Also some form of gumbo around the wire where it enters, as you already spotted.
Awesome, thanks soooo much Glen and Ron.
I have cancelled my Spruce order and will re-install this Saturday.
Cheers
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