Fuel Flow - Recommendations

[scre80]

Hi All,

 

I have just purchased a recreation aircraft, and I was thinking about putting a fuel flow instrument in, that was until I saw how much the fuel flow sensors cost!!!.

 

Is there any recommendations / thoughts around this, and if anyone knows where to get them a lot cheaper than $325!! (I need to get 2 sensors)

 

I was thinking about the MGL Infinity one

 

Infinity

 

 

[rick morawski]

Hi All,I have just purchased a recreation aircraft, and I was thinking about putting a fuel flow instrument in, that was until I saw how much the fuel flow sensors cost!!!.

 

Is there any recommendations / thoughts around this, and if anyone knows where to get them a lot cheaper than $325!! (I need to get 2 sensors)

 

I was thinking about the MGL Infinity one

 

Infinity

You can get a fuel flow gauge with 2 senders for $325?, please tell me where!

 

 

[scre80]

You can get a fuel flow gauge with 2 senders for $325?, please tell me where!

Let me clarify, $325 each sensor and then the instrument for around $300, so $900 ish all up. Looking for cheaper options!!!

 

 

[rick morawski]

Here's a link to a good one, I have installed on a couple planes.

 

FC-10 Fuel Computer Totalizer Fuel Flow Meter | eBay

 

If you need an extra sender it's about $220 extra so $700ish plus freight.

 

Are you really sure you need 2 senders? If it's because of fuel return line I usually install the sender beyond the fuel return, it works.

 

 

[scre80]

I am still reading and learning about this all. I was reading if there is a return fuel line, you should have a sensor on it to gain more accurate readings.

 

 

[rick morawski]

I am still reading and learning about this all. I was reading if there is a return fuel line, you should have a sensor on it to gain more accurate readings.

Yes, but you can still get the same accuracy if the takeoff for the fuel return is before the fuel flow sender, so the one sender is then measuring the total fuel drawn by the carb(s). Hope you understand that, would be better with a diagram.

What engine is it intended for?

 

 

[scre80]

Yes, but you can still get the same accuracy if the takeoff for the fuel return is before the fuel flow sender, so the one sender is then measuring the total fuel drawn by the carb(s). Hope you understand that, would be better with a diagram.What engine is it intended for?

It is for a 912 UL 80HP

I found the below diagram. So in the below diagram, where would the return line sit between and the sensor? I am guessing the sensor is somewhere before the the elec fuel pump and the return line comes in inbetween the fuel pump and sensor?

 

 

 

 

[rick morawski]

The return line line is separated from the fuel spider and moved toward the mech pump to allow insertion of the FF sender. I will try and get some photos and post them up tomorrow.

 

 

[Jaba-who]

I'm not familiar with rotax so might be talking out line but I am pretty familiar with fuel flow sensor systems.

 

Something that can be an issue is that some brands of fuel flow sensor require physical positioning of the sensor so that the line leading in or out or both has a straight section for some defined length to reduce turbulence or pressure waves that will introduce inaccuracies. So that's something you'll need to consider.

 

I suspect that the cheaper you go the more this may become a consideration.

 

 

[scre80]

The return line line is separated from the fuel spider and moved toward the mech pump to allow insertion of the FF sender. I will try and get some photos and post them up tomorrow.

Cheers, from what I have read, you can have the return line going either back to the fuel tank or back near where the line comes out of the tank (Correct me if I am wrong). If you do the second way though, you need to have it on the correct side of the electric fuel pump.

 

 

[cscotthendry]

Here is another source for the FC-10

 

FLIGHT DATA SYSTEMS FC-10 WITH FT-60 TRANSDUCER from Aircraft Spruce

 

This is the gauge and sender. I think the one gauge will show two engines (or fuel feeds).

 

I have another Flight Data gauge in my aircraft and they work quite well.

 

 

[rick morawski]

Sorry I could not get any good photos so I have edited your drawing a bit primitive.

 

It can be achieved with various brass fittings (I use mostly 1/8" npt bits off eBay.)

 

 

[Old Koreelah]

I did some research and was told that marine units are the same, but cost far less. I didn't take that any further, having found an inexpensive used aircraft unit.

 

 

[scre80]

Sorry I could not get any good photos so I have edited your drawing a bit primitive.It can be achieved with various brass fittings (I use mostly 1/8" npt bits off eBay.)[ATTACH=full]48770[/ATTACH]

Awersome Rick, thanks for that. Totally understand!!! and makes sense. Thanks for this.

 

 

[techie49]

If you need fuel flow sensors, have a look at Futurlec Electronics. They sell a variety of flow sensors for under $20. They are generally a three wire device, open collector and you will need to calibrate them yourself but it's quite easy. You end up with a 'k factor' which reflects the number of pulses output from the flow sensor when you pass 1 litre through it. I use one on a MGL fuel gauge.

 

Paul

 

 

[rick morawski]

Sorry I could not get any good photos so I have edited your drawing a bit primitive.It can be achieved with various brass fittings (I use mostly 1/8" npt bits off eBay.)[ATTACH=full]48770[/ATTACH]

I should have said 1/4" npt fittings

 

 

[facthunter]

Fuel flow readings are a good thing. Having a total flow indication as well is even better. It doesn't eliminate the possibility of a fuel leak upsetting your day or someone stealing fuel from you overnight. It's also good if you have a manually controlled mixture on the carb, to help you quickly get your settings. Nev

 

 

[scre80]

Fuel flow readings are a good thing. Having a total flow indication as well is even better. It doesn't eliminate the possibility of a fuel leak upsetting your day or someone stealing fuel from you overnight. It's also good if you have a manually controlled mixture on the carb, to help you quickly get your settings. Nev

Agree. Check fuel level (actual) before each flight.

 

 

[pluessy]

I have a JP instruments FS-450 fuel flow and totaliser with only one sensor in the line between electric fuel pump and mechanical fuel pump (Royax 912ULS, similar plumbing as shown by Scre80). My fuel flow meter has been calibrated to read the correct fuel flow at cruise power and will read a bit high at WOT and a bit low on descent/low power. This is due to the fixed amount of the returned fuel (3-4lph) compensated at the cruise fuel flow of about 18lph.

 

I have suggested to JP Instruments to provide a calibration function to off-set the return fuel from the total fuel to give a more accurate reading. They replied that they would look into that. Calibration would be easy: electric pump on, engine off, measured fuel flow is return volume.

 

A word of caution: if you have a LSA aircraft, you will need the approval of the manufacturer to change any of the plumbing or instrumentation.

 

Cheers, Thomas

 

 

[scre80]

I have a JP instruments FS-450 fuel flow and totaliser with only one sensor in the line between electric fuel pump and mechanical fuel pump (Royax 912ULS, similar plumbing as shown by Scre80). My fuel flow meter has been calibrated to read the correct fuel flow at cruise power and will read a bit high at WOT and a bit low on descent/low power. This is due to the fixed amount of the returned fuel (3-4lph) compensated at the cruise fuel flow of about 18lph.I have suggested to JP Instruments to provide a calibration function to off-set the return fuel from the total fuel to give a more accurate reading. They replied that they would look into that. Calibration would be easy: electric pump on, engine off, measured fuel flow is return volume.

 

A word of caution: if you have a LSA aircraft, you will need the approval of the manufacturer to change any of the plumbing or instrumentation.

 

Cheers, Thomas

Thanks Thomas. My aircraft is a 19 registered, and I am not doing anything without speaking to our local Lame

 

 

[waraton]

I have taken on a new project which has one of these Mizer Northstar fuel flow monitors installed, it is unserviceable. The company is long gone so replacing it with a new model is not an option. Is there an automotive or marine unit which is functional and sidesteps the aircraft price tag ? I have had a google sqizz and not had any joy, so all gems of wisdom will be gratefully received.

 

 

 

[Roscoe]

I have a JP instruments FS-450 fuel flow and totaliser with only one sensor in the line between electric fuel pump and mechanical fuel pump (Royax 912ULS, similar plumbing as shown by Scre80). My fuel flow meter has been calibrated to read the correct fuel flow at cruise power and will read a bit high at WOT and a bit low on descent/low power. This is due to the fixed amount of the returned fuel (3-4lph) compensated at the cruise fuel flow of about 18lph.I have suggested to JP Instruments to provide a calibration function to off-set the return fuel from the total fuel to give a more accurate reading. They replied that they would look into that. Calibration would be easy: electric pump on, engine off, measured fuel flow is return volume.

 

A word of caution: if you have a LSA aircraft, you will need the approval of the manufacturer to change any of the plumbing or instrumentation.

 

Cheers, Thomas

I have the same in my Jabiru 170, fitted by Jab Factory.

Very happy with it, and their is a kit available from Garmin which connects to s portable gps giving you fuel etc to next waypoint.

 

From memory, the FS 450 cost USD $549 from Aircraft Spruce in USA

 

 

[Yenn]

I think the metering provided by Vans Aircraft would come out at about the same price,

 

MGL make the same sort of gear at about that price.