EIS4000 Fuel Flow sensor - Has anyone tested the maximum flow rate?

I checked the flow sensor recently and noticed that the sensor has a rather small orifice through which the fuel must pass. It appears to be no larger than 0.125" in diameter.

Has anyone taken the time to do a max fuel flow test with a Standard Facet fuel pump setup on their RV?

If so, what flow rate figures did you see.

Also, with such a small constriction I am considering mounting mine inside the engine compartment after the gascolator (ie after the fine filter gauze) to ensure no debris will block the unit.

Any other comments would be welcome.

Doug Gray

I forget the exact number.. I think it was showing 26-28 gph... plenty enough for an O-360...

Same flow gauge as the IO uses. When we tested we had over 150 litres per hour (~40 gal in old money). We are in the some, more, lots type scale. The engine needs some, the pumps provides more and the sensor can deal with lots.

HTH,

Carl

hummmmmmm

I don't have hard numbers for you however the recomendation is double your engine flow rate. I had the same questions for an IO-540. I found that a #10 line (1/2") will give you about 110GPH. The problem is the restrictions like check valves and fuel flow sensors. I wanted to install flow sensor in the line from the main tank to the header tank but found that no one makes a 1/2" full port fuel sensor....oh well.... Check out airflowperformance.com for more info.

There is no regulatory requirement for us to comply with FAR 23 (the design standards for type-certificated light aircraft), but it provides a useful reference.

For aircraft with fuel pumps, FAR 23.955 requires a demonstrated fuel flow capability of 125% of the fuel flow required at max take-off power. This fuel flow must be demonstrated with the fuel flow sensor blocked, so that fuel flows through the bypass built into the fuel flow sensor. If the fuel flow sensor does not have a bypass, it must be shown that there are no probable failures that could reduce the flow capability of the fuel flow sensor below 125% of that for max take-off power.