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Red cube install beside spider

Sylvainsting

Active Member
Hello,

I am going to install my red cube and have some interest to install it between the fuel servo and the spider. For those who choosed the same location, I would like to know if they experimented some "Vapor Lock" because of the proximity of the hoses between the cylinders.

In advance thank you
Sylvain
 
My FF transducer is mounted directly to the flow divider with a NPT nipple. Can't get any closer than that, and I have not seen any issues with vapor lock or inaccuracy.
 
Hello,

I am going to install my red cube and have some interest to install it between the fuel servo and the spider. For those who choosed the same location, I would like to know if they experimented some "Vapor Lock" because of the proximity of the hoses between the cylinders.

In advance thank you
Sylvain

The cubes I have seen mounted under the cylinders, and plumbed between the servo and spider have been covered with fire shield. That is my plan. Good question about experience, though.
 
I've got mine like Michael. Pipe nipple, no sleeving. Its right up front center, so it gets whatever cool air there is coming in. Accurate, stable. Mine is a floscan, but same difference.
 
WE have several flying examples of cubes mounted at or near the spider. We havent heard (in 2+years) of flight time, of anyone having any issues, vapor lock (that was traced back to the location), or any failures. Flow readings have been consistent with those in other locations.
Tom
 
Fuel Servo - Distributor

Mine is on a piece of aluminum (wires UP as specified) in front of the sump. No vapor lock issues.

FF readings do not fluctuate as they did with the FloScan transducer in the tunnel.

See the red cube config Rob Hickman uses (pic in the AFS manual).
 
Sylvain,

We mounted ours there and have 40 hours on it now. No issues, hot starts great, no rough running engine after hot start. Angle valve engine. Fuel flow indicates normally at all times, very accurate.



Tom at TS Flighlines made us up the hoses you see here, great service.
 
Call EI. They will tell you to mount it there. That's what they told me and 350 hours later it's working great. I won't say I do not have hot start issues though...but I suspect it's the same as every other injected engine with a tight set of baffles. That said, it is one more thing to heat soak up there on top of the engine.... She always starts..but complains about it.

If I were to build again, I would put it in the same place.
 
My setup on the Rocket.

29frqzm.jpg
 
My setup on the Rocket.

29frqzm.jpg

I'm looking at going this way on my IO-360. Is your transducer supported anywhere other that with the SS pipe and nipple?

My spider orientation requires that the Cube be installed off the side. I'll have a flexible hose attached to my Red Cube, so will need to support that end of the assembly, but have read about relative movement between spider and cylinders; where my clamps will be, and am concerned about eventual cracking in the nipple. What material is your nipple: aluminum, stainless, brass, zinc-coated brass?

Thoughts?
 
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The short nipple connecting the flow divider and flowmeter is steel. There is no support other than the adel clamp out in front on the stainless tube. And this support is substantial.

I have also read the concerns on the other thread about "cylinder movement". Yes, this is real, but keep in mind that the whole cylinder does not move at an even rate. While the end of the head moves around a bunch and gives the oil cooler mount fits, this is a result of cumulative expansion of the cylinder. It's my opinion that mounting the flowmeter near the base of the cylinder will not cause any significant stress due to relative movement - because there really isn't much. I'd further opine that the pushrod tubes "float" in position, and adding adel clamps to that will further isolate any relative movement of a flowmeter clamped to the pushrod tubes.

The original installation (with the short SS tube) in the other thread looked just fine to me, and I would have flown it without hesitation.

BTW, here is a picture of what I did on the -8 some years ago. The original builder had the flowmeter in the cockpit so I left it there. Doing it again, I would screw it right to the flow divider like the Rocket. And of course used hard line, since that's my "thing". http://www.vansairforce.com/community/showpost.php?p=843640&postcount=4
 
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