Red Cube Placement Opinions

mulde35d · #1 03-19-2023, 09:05 AM

I am installing a fairly traditional fuel system in the RV-10 and need to emplace my Red Cube FT-60. Of course the manual shows it after the electric boost pump and before the engine driven boost pump in the center console. The Red Cube manuals states it must be installed after all boost pumps to prevent vapor lock.

Installing in the center console per the Van's manual is of course the easiest and probably best for the red cube as it doesn't expose the transducer to the heat and vibration of the engine compartment.

Installing after both fuel pumps abides by the manuals, but finding a good location away from heat, vibration, and chemicals is difficult as they tend to fail faster when exposed to those conditions. The firewall would be the best location to mount it in the engine compartment, but that requires some interesting hose routing. Mounting to an engine mount tube is likely best to reduce vibration, but difficult to find a secure mount type (zip ties are not what I would consider secure). The RV-14 solution shown below may be possible, but exposes the FT-60 to exhaust heat and engine vibration.

Which one did you do? Pictures are appreciated if you ended up putting it in the engine compartment.

Mike S · #2 03-19-2023, 09:19 AM

I seem to remember that https://www.aircraftspecialty.com/ makes a special setup that should take care of your needs.

Found a link. https://www.aircraftspecialty.com/PD...er%20Mount.pdf

Auburntsts · #3 03-19-2023, 10:40 AM

Mine is suspended by the fuel line in between the mechanical fuel pump and the fuel servo and covered by a length of firesleeve that Aircraft Spruce sells for this purpose. IOW it’s not rigidly mounted to anything.

Carl Froehlich · #4 03-19-2023, 10:43 AM

Considering the multiple trips around the tree to resolve a fuel flow error on an RV-14, I recommend not mounting it like the RV-14 plans say to do.
Side note - it seems we were not the only ones with this problem - it was a combination of location, vibration and hose lengths. We solved the problem by moving the sender to a new location.

On my first RV-10 build I mounted the sender per plans. If the boost pump was off it gave an accurate reading. Turing the boost pump on the reading jumped up. I also note that on rare occasion during a hard climb fuel pressure would drop below normal (boost pump off). I attribute this to the cube location.

The attached photo shows how I mounted it on the RV-8 project. It meets all the fuel sender install instruction requirements and I can report it is rock solid in use. I will do something similar on the new RV-10 project. I know the steel fittings should be aluminum but this is the only photo I have.

Carl

mulde35d · #5 03-19-2023, 11:00 AM

Quote:

Originally Posted by Carl Froehlich

Considering the multiple trips around the tree to resolve a fuel flow error on an RV-14, I recommend not mounting it like the RV-14 plans say to do.
Side note - it seems we were not the only ones with this problem - it was a combination of location, vibration and hose lengths. We solved the problem by moving the sender to a new location.

On my first RV-10 build I mounted the sender per plans. If the boost pump was off it gave an accurate reading. Turing the boost pump on the reading jumped up. I also note that on rare occasion during a hard climb fuel pressure would drop below normal (boost pump off). I attribute this to the cube location.

The attached photo shows how I mounted it on the RV-8 project. It meets all the fuel sender install instruction requirements and I can report it is rock solid in use. I will do something similar on the new RV-10 project. I know the steel fittings should be aluminum but this is the only photo I have.

Carl

I like the idea of mounting to the engine mount with two adel clamps. Would just need to determine the exact location and hose lengths for that install.

TS Flightlines · #6 03-19-2023, 11:34 AM

While there are many RV10s flying just fine with the transducer in the tunnel, alot of you requested that we come up with a FWF location. WE settled on this location, mainly due to the offset rotation of the flow divider, and the ease of install.
Pictured below is the protoytpe location as tested by our beta testers. Yes, we changed the fittings to steel, and the supply hose was shortened to eliminate contact with the firewall. Current version ships in our FWF RV10 hose package with the integral firesleeved hoses.
WE have done some with the transducer mounted above the servo near the sump parting line. Still takes 2 hoses to do the install.
Most of the divider mounts we've seen put the divider at the top of the case on the centerline. That eliminates the use of our 4 Cylinder version bracket with our alot of changes. So we chose the aft engine location. Maybe not the best for all parties, but it is universal, and it works well.

Tom

Avanza · #7 03-19-2023, 01:29 PM

Pressure drop is stated as 0.5PSI @ 28 Gal/Hr.
This means that with a fuel flow of 14 Gal/ hr you will have pressure drop of
0,125 psi, almost nothing. My own RED CUBE is installed after the electric
puel pump aft of the fire wall. 180 hp engine.
The best installation situation is with electric wires pointing UP.
The fuel line on the outlet port should not drop down after exiting the transducer. Both of these configurations can trap bubbles in the transducer causing jumpy readings.

https://iflyei.com/wp-content/upload...Info-Rev-F.pdf

Good luck

mulde35d · #8 03-19-2023, 03:01 PM

Quote:

Originally Posted by TS Flightlines

While there are many RV10s flying just fine with the transducer in the tunnel, alot of you requested that we come up with a FWF location. WE settled on this location, mainly due to the offset rotation of the flow divider, and the ease of install.
Pictured below is the protoytpe location as tested by our beta testers. Yes, we changed the fittings to steel, and the supply hose was shortened to eliminate contact with the firewall. Current version ships in our FWF RV10 hose package with the integral firesleeved hoses.
WE have done some with the transducer mounted above the servo near the sump parting line. Still takes 2 hoses to do the install.
Most of the divider mounts we've seen put the divider at the top of the case on the centerline. That eliminates the use of our 4 Cylinder version bracket with our alot of changes. So we chose the aft engine location. Maybe not the best for all parties, but it is universal, and it works well.

Tom

It doesn’t appear that the red cube is supported in any way besides the fuel hose. Wouldn’t that result in increased vibration on the transducer? I would think it would have a longer life if it were secured to the mount. Any feedback on longevity from the field without it being supported?

Auburntsts · #9 03-19-2023, 03:53 PM

Quote:

Originally Posted by mulde35d

It doesn’t appear that the red cube is supported in any way besides the fuel hose. Wouldn’t that result in increased vibration on the transducer? I would think it would have a longer life if it were secured to the mount. Any feedback on longevity from the field without it being supported?

8 years and still ticking. If you read EI’s install instructions, they talk about this very type of installation.

TS Flightlines · #10 03-19-2023, 05:23 PM

Gustav---with your installation with the wires up, everything reads fine. If you fly inverted, the wires are down, does the reading get crazy? The answer is no, from many thousands of flight hours over 11 years of installs. Same for the wires pointing to the sides, like our 4 cylinder Lycoming bracket kit. If there is an anomaly, its not the location of the transducer, or its attitude.

Tom