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Rv-7 Red Cube Fuel Flow Installation


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I noticed a lot of different opinions regarding the mounting of the Red Cube (E.I Fuel Flow Transducer) on the engine. How can it be done, and what is the most practical approach? I wanted to gain some insight into others' thoughts on the placement of my Red Cube. On my Rv-7, IO-360 Thunderbolt engine I ended up making a bracket that connects to two existing bolts on the underside of the engine. I used a rubber-sleeved bolt that goes through the cube, with rubber washers on both sides. This allows the cube to float freely. I would appreciate your feedback and thoughts on my approach.


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A good source for installation advice is the manufacturer of the cube, Electronics International, they have installation manuals on their website.
Looks very clean to me. I have mine mounted to the same place on the other side, but I don't have any rubber - it's mounted solidly. I used both bolt holes.

The manufacturer's physical mounting instructions include this: "This transducer must be suspended between flexable hoses on the inlet and exiting ports. The hoses must be supported within 6 inches of the transducer."

Most installations I've seen here show a physical mounting of the cube. The strange thing about the advice they give is, if the cube is not supposed to be mounted, why did they include 2 mounting bolt holes? Perhaps over time they have learned that solidly mounting the transducer where there is vibration reduces the service life of the transducer.


I've seen a lot of installations using adel clamps, which also provides some dampening of the vibrations. I guess if mine quits and I have to replace it, I'll re-install a new one with some kind of rubber mount to reduce vibration transfer to the transducer.