electric fuel pump

[larrym 1]

My Avid came with an electric fuel pump in addtion to the normal pulse pump. Anyone know why? The fuel system is plumbed like the book, namely a pressure assisted gravity feed. I am redoing things, and am consodering the remaoval of electric pump.... ideas?

Thanks,

larr

[Av8r3400 1179]

I know several people who have had pulse pump failures. An electric backup will save you from an engine out in that situation.

I'm adding one to my project plane.

[C5Engineer 1170]

I pulled the fuel line off my pulse pump with 5 gallons on board to test the gravity feed and fuel shot 3 ft away. Do you have the wing spar header tank? Maybe those provide better feed than the kitfox tanks at the bottom of the fuse? Electric is a good back up I guess. Seems if it was really necessary Cessnas and everything else with a highwing would be running them too??

[Av8r3400 1179]

I pulled the fuel line off my pulse pump with 5 gallons on board to test the gravity feed and fuel shot 3 ft away. Do you have the wing spar header tank? Maybe those provide better feed than the kitfox tanks at the bottom of the fuse????/>/> Electric is a good back up I guess. Seems if it was really necessary Cessnas and everything else with a highwing would be running them too??

Cessnas don't have a header tank that can be mounted below the engine like a Kitfox or Avid. They also don't rely on pitot pressure to push fuel.

If you decide to add inline filters that is definitely reason to have a pump.

Edited 16 Jan 2013 by Av8r3400

[dholly 718]

If you decide to add inline filters that is definitely reason to have a pump.

^This.

I've resolved to add an ePump and fuel flow when the weather warms, plus a filter with a Jim Chuk style filter bypass. Will need to ditch my minimalistic 'center console' and re-route my fuel line to make it all work.

[akflyer 1427]

I thought about taking the electric pump out of mine when I was doing the rebuild, but I am VERY glad I left it in. I was taking off from a small lake and had barely cleared the trees when I saw the fuel flow start dropping big time! Just as the engine started to sag I hit the electric pump and got the fuel flow back. Turns out that the fuel filter was plugging off with little bitty hairs that were not visible when I was just looking at the filter during my normal preflight. I was able to swing around and land at a bigger lake and change the filter. Without that back up pump I would have been eating trees.

I am normally a "keep it light and simple" kinda guy, but the one time I really needed it, that pump saved my ass from a very long hike and a wrecked plane. We are really only talking about a few ounces here, not a few pounds worth of fuel pump.

[High Country 69]

what kind on fuel pump are you guys running or would you recommend? how many PSI

-Robert-

[akflyer 1427]

mine is a facet pump. I think it is around 4 PSI.

[EDMO 1078]

what kind on fuel pump are you guys running or would you recommend? how many PSI

-Robert-

The most generally used is the square Facet - probably cheapest and best at about $40 - But read on.......

Facet makes a ton of different pumps, with different pressures, fittings, backflow check valves, or not, and frontflow check valves, or not - all internal....You can download the list at the Facet website.

For mine, I plan on 2 pumps, in parallel, 4-7 lbs pressure, with backflow checkvalves, and no frontflow(flow-thru) checkvalves. Weight is 2 or 3 lb each. Should run 3/8 fuel lines for my Soob.

ED in MO

Edited 17 Jan 2013 by Ed In Missouri

[EDMO 1078]

I thought about taking the electric pump out of mine when I was doing the rebuild, but I am VERY glad I left it in. I was taking off from a small lake and had barely cleared the trees when I saw the fuel flow start dropping big time! Just as the engine started to sag I hit the electric pump and got the fuel flow back. Turns out that the fuel filter was plugging off with little bitty hairs that were not visible when I was just looking at the filter during my normal preflight. I was able to swing around and land at a bigger lake and change the filter. Without that back up pump I would have been eating trees.

I am normally a "keep it light and simple" kinda guy, but the one time I really needed it, that pump saved my ass from a very long hike and a wrecked plane. We are really only talking about a few ounces here, not a few pounds worth of fuel pump.

:BC:/>

What kind of flow meters are you guys using? cost & size? I have a pressure meter, but no flow meter. Guess this will be good?

ED in MO

[SuberAvid 617]

What kind of flow meters are you guys using? cost & size? I have a pressure meter, but no flow meter. Guess this will be good?

ED in MO

Ed, the MGL Flight -2 instrument with fuel flow sensor. This instrument gives you fuel flow, fuel remaining based on tank level sensors or you can preset your fuel amount at start of flight if you dont have tank sensors, fuel time remaining, fuel distance remaining, low fuel warning; all based on the fuel level, fuel flow and airspeed calculated by the instrument; plus all the other things it does.

3/8 fuel lines are overkill for the EA81. I used 5/16 but when you look at the orifice that the fuel flow sensor has in it (placed upstream from the fuel pumps) it is probably only about 1/8" at the largest and has smaller inserts for readings at the lower fuel flows. I didn't install any restricting inserts in mine which may cause it to be less accurate at the low fuel flows but I wanted the larger size so I didn't have too much restriction.

[EDMO 1078]

Ed, the MGL Flight -2 instrument with fuel flow sensor. This instrument gives you fuel flow, fuel remaining based on tank level sensors or you can preset your fuel amount at start of flight if you dont have tank sensors, fuel time remaining, fuel distance remaining, low fuel warning; all based on the fuel level, fuel flow and airspeed calculated by the instrument; plus all the other things it does.

3/8 fuel lines are overkill for the EA81. I used 5/16 but when you look at the orifice that the fuel flow sensor has in it (placed upstream from the fuel pumps) it is probably only about 1/8" at the largest and has smaller inserts for readings at the lower fuel flows. I didn't install any restricting inserts in mine which may cause it to be less accurate at the low fuel flows but I wanted the larger size so I didn't have too much restriction.

The 3/8 Aluminum tube is about 5/16 inside - Dont think I want any 1/8 restrictions in lines. We used 3/8 on the C-90, and have the fittings and tubing, so going with the cheapest, easiest.

Thanks,

ED in MO

[thebriman 69]

Im down for maintenance right now and I want to add the electric fuel pump as a backup.  I know Leni and others with the 582 have the setup with dual pumps.  I guess series and parallel is my own choice as Mike Stratman said in one of his articles, how are you guys set up.  Pulse or electric first? Series or Parallel?

[allonsye 85]

RE: 582 Gray.

 

I thought I'd revive this thread.

 

I've a Facet Elec fuel pump on my firewall that feeds into the vacuum driven.  But I'm wondering if this "series" set up is optimum over adding extra lines and fittings to create a "parallel" setup.  Soliciting comments, photos of your setups and suggestions from the collective. eg. Should the elec feed through the vacuum pump (which it is presently) or around it directly to the carbs?

Edited 12 Jun 2015 by allonsye

[EDMO 1078]

I have a full page of Facet fuel pump models and specs - With a dual parallel pump setup like I was planning, I chose the ?---09 pumps because they allow free gravity flow and have a check valve to block reverse flow and match my 2-6 lb pressure range for my Holly 5200 carb.  There will be a shutoff valve in the single line to the engine.

     However, I planned this in Alaska Bush Country - Here in tame Missouri, I probably only need one, and that would save weight.

 

I guess you could add a check valve to a line that is connected to a Facet pump that don't have one.  I don't have a pump on my Soob engine.   I don't know about Rotax.

You can print this chart from their site.

EDMO 

Edited 13 Jun 2015 by Ed In Missouri

[Dusty 126]

I have a low pressure facet mounted before the pulse pump,(it is easer as the pulse pump is also the splitter).

This systym has served me well for 300+ hrs,

I am currently rebuilding a kf4 and was surprised to find in level attitude the tank flow is 22litres per hour at the carb with gravity alone!

With the exception of a real steep climb or a restriction, the flow is in excess of a 582's maximum requirement,

Also wing tanks possibly run slight positive pressure so don't frett too much about fuel supply,but redundancy is a good thing

[allonsye 85]

I have a low pressure facet mounted before the pulse pump,(it is easer as the pulse pump is also the splitter).

This systym has served me well for 300+ hrs,

I am currently rebuilding a kf4 and was surprised to find in level attitude the tank flow is 22litres per hour at the carb with gravity alone!

With the exception of a real steep climb or a restriction, the flow is in excess of a 582's maximum requirement,

Also wing tanks possibly run slight positive pressure so don't frett too much about fuel supply,but redundancy is a good thing

Thanks Dusty. I'll leave well enough alone.  This aircraft is set up that way as well and had 300 hrs TT.  When I received it, the motor and plumbing were off and I wasn't exactly sure how it was plumbed.  I have a fuel pressure gauge. I think I'll T off the elec pump to the gauge to monitor the pressure.

[EDMO 1078]

I haven't done any research on a fuel pressure guage - I would like to find a cheap one of course - I had a deal on a FC-10 flow meter and got burned by ad on ebay - Got money back, but FC-10 was a scam by someone who was listed as "mearoger" in Arkansas.

EDMO

Can you believe:  Spruce lists a fuel pressure gauge for about $8 - Maybe $10 in newer catalogs.

When "aircraft" gauges are $125 to $250 !!  Guess I need to visit my autoparts store...

EDMO

Edited 15 Jun 2015 by Ed In Missouri