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Floscan

Steve Sampson

Well Known Member
I am puzzling about where to mount the Floscan on a carburated 320 in a -4.

One shoud mount it beyond the gascalotor which will be located on the lower firewall. However I have almost decided to put it between the selector valve and the gascolator. The reason I do not want it in the engine compatement, beyond the gascolator, is that since I expect to run Mogsa through the engine at times and I see it as another heat sink to promote fuel vapourisation.

This leads me to ask two questions and invite comment.

1. In the event that small particles of crud get into it that the gascolator would have filtered out, can I assume the risk is only that it will not measure correctly, not that it will block the fuel flow?

2. In normal operation is it in fact very suceptible to particles. I rarely find anything in the gascolator.

Any other thoughts?

Thanks, Steve
#4478
 
The passages in the Floscan are relatively large. I cannot imagine anything that gets by stainer in the fuel tank would lodge in the floscan. I don't think it is all that suseptable to an occasional particle either.

The mechanical fuel pump will be a huge heat sink, dwarfing the effect of having a floscan fwf. Thought about eliminating it and running two electric pumps, a primary and a backup? I know - need electrical redundancy!
 
zav6a said:
The passages in the Floscan are relatively large.

Zav6a - thanks for that. No if the Floscan is not a problem I will just put it inside the cabin. It wont be my primary approach to fuel measurement. I'll just do the normal thing of putting the gascolator on the firewall and minimise what is out there. In fact I have never found vapour lock much of a problem, perhaps because I am flying in the UK and Europe and it never actually gets very hot! I'm strictly VFR so I will save the weight.

Thanks again, Steve
#4478
 
Hi guys,

I am a sales and tech support rep for Electronics International.

You are going to want to install the flowscan transducer after the fuel pumps. Ideally the flowscan should be mounted in flex-line just prior to the carb.

Failure to do so could lead to very peculiar readings.

What fuel flow indicator will you be using?

Mathew Sharp
Electronics International Inc.
www.buy-ei.com
[email protected]
Tech Support: 877-318-6060
 
Last edited:
Mathew Sharp said:
Hi guys,

I am a sales and tech support rep for Electronics International.

You are going to want to install the flowscan transducer after the fuel pumps. Ideally the flowscan should be mounted in flex-line just prior to the carb.

Failure to do so could lead to very peculiar readings.

Oh well, so much for following the instructions that came with the darn thing. :confused:
 
I had one event that I attribute to vapor lock. But it involved mogas with 15% ethanol. Got to burn that american corn!
 
szicree said:
Oh well, so much for following the instructions that came with the darn thing. :confused:

I am interested in what unit/model might suggest placing it somewhere else :confused:

Anyhoo, I was speaking in general terms of how I would recommend to a customer proper installation of a flow sensor with our FP-5(L) unit. Our FT-90 and FT-60 units are interchangeable with the Floscan units. Therefore I'd think the installations would be the same.....or atleast similar. :D

Mathew Sharp
 
I have the FP-5L and love it! I put the transducer in the cabin between the electric pump and the gascolater with about 6 or 8" of aluminum tube on either side. Works perfect, FF increases when the electric pump is on but other than no problems whatsoever.
 
Wanting to install my FP-5L

OK, come on.... Which is it?

It's best to install BEFORE (as in the cockpit) OR AFTER the mechanical fuel pump....

I'd like to install my EI FP-5L and get the most accurate use of it.
 
Ideally the flowscan should be mounted in flex-line just prior to the carb.

Failure to do so could lead to very peculiar readings.

What fuel flow indicator will you be using?

Mathew Sharp



Mathew - thanks for your input.

I used to fly an RV that was organised Fuel valve / electric pump/floscan/ mechanical pump and it worked extremely accuratelt. I always wondered though what the issues were around blockage. How sensitive it was to small particles in the fuel. I never had a problem but that was the reason for my query. The instrument was a Grand Rapids 4000.

Now I am building an RV4 and in view of the comments I will do it the same, except the instrument will be different. Perhaps Dynon or AFS. Those instruments are the attractive ones to me. (Sorry!) I struggle as to why EI thinks you would get 'peculiar readings' organised this way. Fuel is a non compressible fluid so it must all move in unison.

To me for many reasons it seems better to only put things in with the engine that have to be there. In this case the mechanical pump and the gascolator, not least for reasons to do with minimising the amount of heated fuel.

Thanks for your input. Regards, Steve.
#4478
 
K-Value for Dynon

I bought a Floscan 201B-9 to use with my Dynon. Install Manual asks for a K value that you get from the TICKET attached to the Floscan. I had no ticket attached when it arrived.......does every Floscan have a different K value or are they similar? If they are identical what is the K-Value for this model?

Thanks,
Dean
40449
 
FloScan mounting

I mounted my FloScan on the firewall between the Gascolator and the mechanical fuel pump, with 5" inches of aluminum tube before the sensor, and with Aeroquip hose after. When the electric fuel pump is on, the FloScan as read by the GR 4000 reads 50% high. The electric pump is quite a thumper and I presume the pulsations trigger false signals in the FloScan.
Leland
 
Ram Air Cooling?

Leland said:
I mounted my FloScan on the firewall between the Gascolator and the mechanical fuel pump, with 5" inches of aluminum tube before the sensor, and with Aeroquip hose after. When the electric fuel pump is on, the FloScan as read by the GR 4000 reads 50% high. The electric pump is quite a thumper and I presume the pulsations trigger false signals in the FloScan.
Leland

Did you provide any type of cooling such as cooling shroud and ram air? Currently I have gascolator & mechanical fuel pump (of course) forward of firewall. Both have shrouds and ram air ducts.

My biggest concern is creating a vapor lock problem.

Thanks,
 
201B-9 K value

K value for 201B-9 is around 42,000. The specific number range changes from unit to unit. Near one of the bolt holes, you will see a letter stamped on the body. You will need to contact Floscan to obtain the more specific range to your unit.
 
FloScan shrouding

BillyBob said:
Did you provide any type of cooling such as cooling shroud and ram air? Currently I have gascolator & mechanical fuel pump (of course) forward of firewall. Both have shrouds and ram air ducts.

My biggest concern is creating a vapor lock problem.

Thanks,

No BillyBob, I did't cover the gascolator or FloScan with shrouding. I do have ram air on the mags and the alternator, but nothing special with the fuel system. So far no vapor locking, but then most of my flying is in Northern California and I only use 100LL. Vapor locking is more common with fuel injection after heat soaking on the ground.
Leland
 
A couple of things on fuel systems from somebody who ran MoGas in an RV-4 for 1000 hours in hot surroundings. First, I only had vapor lock twice in 10 years, both times not following good summer practices. One is I always open my oil door when I shut down to allow heat to escape from the cowl directly above the fuel system. Second, I use a 30 second runup at 1700 rpm before T/O with a hot engine/hot day to get cold fuel into the system. In the RV4 builders manual they have drawings for a vapor pressure release line plumbed into the main fuel line. I didn't install it but used the runup which worked well. Since I have installed a 170HP (9.3:1 comp)0-320, I run an AVGas mix which hasn't shown any vapor lock tendencies.
I use a blue gascolator mounted on an angle bracket very similar to the H2AD installation pictured in the gascolator thread above.
I mounted my Fp-5 flowscan per EI's instructions between the mechanical fuel pump and the carb with good results. I fire sleeved the flowscan and put a heat shield on the nearest exhaust pipe. I also put a cooling shroud and cool air blast line to my mechanical fuel pump.
My 2 cents..

RR
 
Put the gascolator inside the cabin?

The issue of the -4 firewall and the gascolator has been preoccupying me the last few days. I would like to float an idea and see the reactions I get. I am seriously considering putting the gascolator in the compartment beside the stick, right by the fuel pump. My logic for this is as follows:

1. I don?t see it as a water collection point since any water will appear at the wing drains. I would not plan on draining at that location every flight. Just the occasional inspection for crud.
2. I do see it as a filter and that is where an injected engine filter would be?or thereabouts.
3. If it is not on the firewall the connection to the fuel pump is simple and a small amount of fuel is heated if running Avgas. (Vapour lock issues.)
4. Simplicity of installation.
5. I would quite like to put a ?C? piece on the firewall to smooth the exit path for air. It would simplify that.
6. And there is another reason which I have forgotten.

Thoughts?

Thanks, Steve.
#4478
UK
 
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