912 Return Fuel line from Distribution Block

Turbo_Boss

Air Boss
Joined
Mar 20, 2008
Messages
78
Location
Panama Rep. of Panama
Aircraft
Quicsilver MXII
Guys, please review the pic. This is how my fuel lines are intalled on my 912

On top of the 912 there is a distribution fuel block. Intead of intalling the
fuel return line to the main tanks, my mechanic recomend me this draw.

What you think. Its OK?

THX,

Isaac

xRansfuelsystemsimplificado.jpg
 
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Guys, please review the pic. This is how my fuel lines are intalled on my 912

On top of the 912 there is a distribution fuel block. Intead of intalling the
fuel return line to the main tanks, my mechanic recomend me this draw.

What you think. Its OK?

THX,

Isaac

xRansfuelsystemsimplificado.jpg



You can’t return your fuel to the supply line, the fuel return (if any in carburetors systems) has to go directly to the tank with a non return to valve in between.

Thanks
Albert
 
The scheme in the drawing might work, but it could reduce the ability of the return system to clear a vapor lock. Plumbing the return line back to the tank would be the right way to go, but would make the fuel flow senser inaccurate.

I think you'd need to replace the single, four-way passive block with a pressure regulator after the mechanical pump, which would have the third port feeding the return line, with the output port feeding the fuel flow sensor, then a tee to the carbs.
 
The scheme in the drawing might work, but it could reduce the ability of the return system to clear a vapor lock. Plumbing the return line back to the tank would be the right way to go, but would make the fuel flow senser inaccurate.

I think you'd need to replace the single, four-way passive block with a pressure regulator after the mechanical pump, which would have the third port feeding the return line, with the output port feeding the fuel flow sensor, then a tee to the carbs.

Hey Paul,

Thanks so much for your advise. I think I will follow your advise plumbing the return line back to the tank.

About the second paragraph, I dont undertand it. English is my second lenguage and I have read that second paragraph several times and I still dont undertand it......... I really apreciated if you can you draw me a schematic.

Thank you for your time and help,

Isaac
 
You can’t return your fuel to the supply line, the fuel return (if any in carburetors systems) has to go directly to the tank with a non return to valve in between.

Thanks
Albert

Hey Albert,

I dont undertand what you mean with: with a non return to valve in between.

Do yo mean that the return fuel line go directly to the fuel tank and do not intall anything in that line?

THX,

Isaac
 
Hey Albert,

I dont undertand what you mean with: with a non return to valve in between.

Do yo mean that the return fuel line go directly to the fuel tank and do not intall anything in that line?

THX,

Isaac


El retorno del combustible debería ir directo al tanque con una válvula de no re-torno(ve círculo rojo) a los carburadores, quiere decir, qué la gasolina sobrante no pueda volver a los carburadores. Estas valvulitas de no retorno las puedes compra en los negocios que venden accesorios de automóviles, y no cuestan casi nada. Ve el link abajo.

http://www.absngroup.com/Non-Return-Valve-Check-Valve-Fuel-Tank-Breather-one-way-valve.htm


Buena suerte
Albert


lacorrectamanera1.jpg
 
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2 sensor. Feed sensor. Return sensor. Wiring and plumbing techniques useful to all builders.
 

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I'm not a builder, but instead of using two fuel flow sensors couldn't you make the 'Fuel Distribution Block' a single output line and just put the EIS Fuel flow sensor before the 'T' to both carburetors?
 

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Bump. Has anyone installed a single fuel flow sensor successfully?
 
Hi

i never installed a single fuel flow sensor successfully at this time , but i have to with my setup

i will test my EFI with one and also with 2 fuel flow turbine with a return style and dead end fuel rail setup

i study many... type of fuel system... for my mogas turbo EFI setup because with mogas ethanol heat and altitude that can create many problem and engine stop that can be eliminated with good instalation and fuel problem understanding

i can try to help you if you explain to me your setup

you want to instal a single fuel flow sensor like a ft60 red cube on a rotax 912 ? or other engine ? efi or carb ?
 
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i imagine Many here run rotax 912 - 914 with one ft60 red cube fuel flow sensor , it is a fairly simple instalation..

with a dead end fuel rail or carb setup with a fuel pressure regulator return to the fuel tank before the carb

with a efi system you have 2 choice , with fuel rail dead end like the yamaha nytro 3 cylinder NA

the fuel pressure regulator is on the fuel pump inside the fuel thank , you can run one fuel flow sensor only before the fuel rail

with the yamaha 3 cylinder turbo sidewinder , the fuel pressure regulator is at the exit end of the fuel rail with the fuel return to the tank , like the rotax 915 ?

normally you need 2 fuel flow sensor with a setup like this , one before and one after the fuel rail

the secont is substracted from the first or primary in your EFIS

for me i have one ft60 red cube and i order 2 other fuel flow sensor - from :KYIV Ukraine

the fuel flow sensor is to test on my engine dyno in the software for best accuracy fuel consumption at all power setting

and for BFSC brake specific fuel consumption , pound per horsepower per hour

with my efi system after the fuel injector characterization linearisation table info is correcly put in the software , maximum flow cc min vs pressure and dead time vs 3 D voltage table

the efi system can calculate the accurate fuel flow or fuel consumption with the fuel injectors opening time duration at all power load and rpm setting
 
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This is from an old post
 

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Hi

is this your setup ? and is it working ? like this , or it is only an example

i see only one fuel pump , the main fuel tank is gravity feeding the small half... gallon swirl tank ?

i will explain to you what i learn and why , in a engine out it is always the smaller things that ad up

and stack up , fuel system can look really simple , some say it work like this , but sometime it can work.. to the environemental condition it cant... fuel heating vapor lock , fuel frothing boilling , fuel pump cavitate

with mogas depend on many factor , fuel composition , state , season , state altitude , all can play on RVP reid vapor pressure

fuel volatility

i dont like small swirl tank , or small header tank with fuel return in it , fuel heating problem prone

fuel return is always for me in the main big fuel thank , bigger heat sink fuel mass

Steve Henry on his efi stol plane dont put smaller than 5 gallons header tank if he return fuel in it..

i know a small plane in USA heat with small header tank with 2 fuel pump that have an engine out and crash damage the

plane with a efi engine , the engine restart after the crash like there have never a problem...

i will monitor and data log fuel temperature , because i have it in my flex fuel ethanol sensor , and the fuel model in my efi system work with fuel temp to compensate for fuel density change..

is it for your raf 2000 subaru engine ?

is it your system in the picture ? before i can tell you my idea on the installation of your fuel flow sensor

and fuel system configuration choice
 
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Hi

is this your setup ? and is it working ? like this , or it is only an example

i see only one fuel pump , the main fuel tank is gravity feeding the small half... gallon swirl tank ?

i will explain to you what i learn and why , in a engine out it is always the smaller things that ad up

and stack up , fuel system can look really simple , some say it work like this , but sometime it can work.. to the environemental condition it cant... fuel heating vapor lock , fuel frothing boilling , fuel pump cavitate

with mogas depend on many factor , fuel composition , state , season , state altitude , all can play on RVP reid vapor pressure

fuel volatility

i dont like small swirl tank , or small header tank with fuel return in it , fuel heating problem prone

fuel return is always for me in the main big fuel thank , bigger heat sink fuel mass

Steve Henry on his efi stol plane dont put smaller than 5 gallons header tank if he return fuel in it..

i know a small plane in USA heat with small header tank with 2 fuel pump that have an engine out and crash damage the

plane with a efi engine , the engine restart after the crash like there have never a problem...

i will monitor and data log fuel temperature , because i have it in my flex fuel ethanol sensor , and the fuel model in my efi system work with fuel temp to compensate for fuel density change..

is it for your raf 2000 subaru engine ?

is it your system in the picture ? before i can tell you my idea on the installation of your fuel flow sensor

and fuel system configuration choice

This was a topic on the forum years ago. And for some reason all those post are not in the search.
This is Auzzie Paul's drawing I pulled using a Google search on the forum. The old guys may remember this.
 
El retorno del combustible debería ir directo al tanque con una válvula de no re-torno(ve círculo rojo) a los carburadores, quiere decir, qué la gasolina sobrante no pueda volver a los carburadores. Estas valvulitas de no retorno las puedes compra en los negocios que venden accesorios de automóviles, y no cuestan casi nada. Ve el link abajo.

http://www.absngroup.com/Non-Return-Valve-Check-Valve-Fuel-Tank-Breather-one-way-valve.htm


Buena suerte
Albert


lacorrectamanera1.jpg
I see from this upper old thread this 2011 post ? number 8

what look like the Ukraine flag color

on another experimental flying forum today i see a post from Our Friend Meglin (y)

1653863241896.png
 
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