Mechanical Fuel Pump required?

[dlomheim]

I have an RV-3 I'm restoring and I'm planning on flying it with just a facet electric fuel pump. My question is: Is there anyone else out there running with just an electric pump, and a fuselage mounted fuel tank? If so, I'd be curious to know if it gravity feeds okay at full power, and at VX type speeds / angle of attack...

I plan on verifying that mine will flow sufficient fuel during the testing phase while at a safe altitude over the airport. If this fails then I'll go ahead and put a mechanical pump on it...

Thanks for any info...

Doug
RV-3 Restoration nearing the end!

 

[Ironflight]

I can tell you that the O-290G in the RV-1 was configured that way Doug, and we didn't have any fuel delivery issues during the 80 hours or so that we flew it in 2011.

 

[mgon]

I owed an RV3A for 10 years - 0290D2 w/ Fuselage Tank.
I ran a engine driven pump and a back-up facet elec pump.
Gavity head pressure through the pump won't be enough.
if the pump fails - fill the tank to 1/2, disconnect the hose
at the carb and try it.
I believe you want 150% gal. per hr what you would burn.
If you can only use a elec. pump have two, one as a back-up.

MG

 

[fixnflyguy]

I do

I have an RV-4 running an O-320H2AD which I did not install a mechanical fuel pump on due to the unique location of the mount pad on that engine. I utilize 2 Facet electric pumps in series with the "boost pump" installed in the center tunnel per the plans, and a firewall mounted "fuel pump" just after the gascolator. Either pump will operate the aircraft normally , and I use the "boost pump " and "fuel pump"for take-off and landing as you would if there were an engine driven pump. The "fuel pump" remains running at all times, and both have their own switch, wiring and cuircut breaker. I feel they are as reliable as any engine driven pump, and future plans will install a back-up battery for any reason I would need to kill the main electrical system. There are others who run similar set-ups and seem satisfied. So for the RV-3, I dont see any reason you couldnt do the same. I know there are -3's with header tanks, and others with wing tanks similar to the -4.

 

[N941WR]

Why not change the accessory case and add the fuel pump?

Check out the engine page of my website, it details how to make the swap. While you are at it, you can add an oil filter.

 

[dlomheim]

Final Fuel Configuration

I finally finished up my fuel line configuration where I added a TEE to the supply hose to the facet pump in order to bypass it so fuel will gravity feed around it to the gascolator and carb. I also installed a check valve just to be sure fuel doesn't end up looping at all when the pump is running. I had hoped to begin taxi testing this weekend but now the weather has soured out, so will be delayed for a while...

https://www.dropbox.com/s/c89gkek81hrqxum/Fuel bypass.jpg?n=49338394]

Doug Lomheim
RV-3 Restoration nearing the end!