Fuel Flowmeter

[Steve Fisher]

I am trying to decide which flowmeter to install in my Patrol. Does anyone have good or bad comments about either of these transducers - Flowscan 201B and Electronics International FT-60?

Steve

[jaredyates]

Steve, please post each question in just one sub-forum. It gets really confusing when we have two conversations about the same thing.

I used the FT90 gold cube and it has been great. I was able to get sufficient flow with it, but did not try the more restricted FT60.

[marcusofcotton]

Dynon used to recommend Floscan but on their tech support they say that the ft60 has much less restriction. EI says ft60 requires engine driven fuel pump. Their data shows ft90 gas much less pressure drop than the ft60. Manufacturer's data from both on restriction indicate EI less than Floscan 201b.

[JimParker256]

I'm using the EI "gold cube" FT90 in my Citabria (O-200 powered), and it works very well. Usually accurate within about 1/2 gallon on full tanks (adding 30+ gallons to 39 gallon tanks). I'll do the same on the Patrol.

[Battson]

I like the performance of the EI Red Cube FT60, but the fuel pressure drop is a consideration if you're not going with fuel injection. In hindsight the FT90 would be a nicer option, but the cost is higher. I understand that any transducer will give an accurate value once the avionics are calibrated correctly, so reliability and cost seem like more important considerations than accuracy.

Very rarely, my FT60 tends to over-read for a short period of time, but only in certain special circumstances. I can't say why this happens with certainty, but I have a theory. It could be related to my specific install, which doesn't exactly comply with manufacturer's recommendations, or it could be caused by the way I operate my system / aircraft. I think the transducer gets air bubbles caught inside it after certain rare events like turbulence on finals with low fuel aboard and power off - maybe unporting a tank and allowing bubbles to collect in the transducer body. The transducer over-reads for a short period of time after certain operational conditions, gradually returning to normal, presumably while the bubbles clear. I find that switching on the fuel pump (which is downstream from the transducer), corrects this high reading while the pump remains on. If I leave it alone, the problem clear itself in a few minutes. I have hypothesised that the lower obstruction passageway in the FT90 might alleviate this problem.

I would enjoy flying with a fuel flow transducer, because I do so much lean of peak EGT running. My wallet wouldn't be caught dead without one, given the choice.

[Luke68]

Where is the best place to install the flow meter? Under the floor seems to be the best place to achieve the straight runs either side of the sensor

[Mark Goldberg]

Usually the transducer has some guidance as far as placement. Mark

[jaredyates]

I found a nice spot just off to the left of the tunnel.