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I am confused as to when in the fuel line/system the Red Cube is installed.
Does it go in the cabin before the Gascolator or after the firewall and gascolator?
Also is a fuel filter needed in addition to a Gascolator?

This one seems to have gone through to the keeper (those of you in the US and Canada will have to work that one out) and I know it has been covered before but I thought it raised a question that I wasn't too sure about myself. I have only fitted a gascolator, and not a fuel filter. I checked the mesh size of the gascolator that I fitted and the micron number was pretty close to that of available fuel filters. It has been OK for 5 years. I checked the mesh last 100 hourly and it was still clean - I only use avgas which seems much cleaner than mogas. I would be interested to hear other opinions.

Regarding the location of the fuel flow sender, I have mine between the gascolator and the engine fuel pump, in a position where the flow is going up-hill. Obviously that arrangement will not apply to those using an Aerocarb.

Peter
Sonex 894
Jab 3300, 340 hours

AeroVee with AeroInjector
I have a fine-mesh fuel filter on the engine-side of the firewall. Originally it was directly at the firewall, with the Cube then attached to the outlet side of the filter. The readings were COMPLETELY inaccurate. Not even close, and fluctuating wildly even in level cruise flight. So this year at my annual I swapped the two, and put the Cube on the firewall, and attached the filter to the outlet side of Cube. So now I have: firewall, Cube, filter, short length of braided hose, AeroInjector. The readings are now far more accurate. It still seems to show a little faster fuel flow than reality, but not by much, and I'd rather have it read that way than the other way (reading slower fuel flow).

Not flying yet but doing taxi/tune up operations and the red cube seems to be reading correctly...firewall-"T" for drain valve-40 micron filter-cube-fuel hose-Aeroinjector.

See page 11 on the photo album In this forum for more pics.

The instructions with the red cube emphasizes the need for long smooth entry, and that seem to be the key, at least in my case. I am getting very good accurate readings even though the red cube is in circuit after both the engine driven and aux electric fuel pumps (CAMit 3300 with Bing) but I have a length of plain 3/8" aluminum tube running half way across the firewall then making a U turn up and back a few inches before entering the red cube. Then short straight fitting and into hose to the Bing carb.
David A.