F

Flyer68

Well Known Member
Has anyone tested their fuel lines for leaks, w/air and soapy water?
I am at the point where I will be covering access to the lines and would like to do it now, but have not seen where anyone else has done it. Maybe it's too easy to talk about, BUT, not for me.
Any help,w/pictures would be appreciated.

Bill
 
One method to pressure test fuel lines...

Flyer68 said:
Has anyone tested their fuel lines for leaks, w/air and soapy water?
I am at the point where I will be covering access to the lines and would like to do it now, but have not seen where anyone else has done it. Maybe it's too easy to talk about, BUT, not for me.
Any help,w/pictures would be appreciated.

Bill
Click to expand...

The fuel lines can be tested like any piping. Plug the ends, install a gauge and a means of pressuring the line. Wait 24 hours and check for pressure loss, keeping in mind that pressure will vary with temperature. Soap test all the connections. The best soap is the kind that comes in a little bottle with a hoop that the kids use to blow bubbles. There is one kind of kiddy soap that blows durable bubbles, don't use that, it makes a sticky mess on the fittings. Dishwashing soap in water mixture also works. You can experiment with soaps on an intentional leak to see how they work.
Here is one idea for a pressure testing set up. The gauge in the picture is a inches water column gauge, better would be a gauge so you can test the fuel lines to about 1.5 to 2X working pressure or about 5 psi:
[url=http://tonytessitore.smugmug.com/RV-12Project/RV-12-Fuselage/8010094_YTLQe#636959455_4jyFi-A-LB][/URL]
Note cap on the return line and schrader valve to hook up a bicycle pump. At the other end use fittings and a piece of hose to jumper between the fuel line and fuel return line:
632922991_NovC3-M.jpg


Caution note: When ready to test the fuel tank you cannot use much pressure or it will ruin the tank. The plans recommend a balloon test for the tank.

Tony
 
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I soap-tested my lines at 60 psi. I did this while the fuselage was on its side after connecting the gascolater and before running the wiring - while I had plenty of easy access. I used a rubber host to join the supply-return lines at the (future) tank like the picture above. (Tank is not yet built.) Then I borrowed a couple of fittings to be able to cap the exits - what you need is not in the kit. Found that the line connected to my upper forward bulkhead fitting needed tightening. Obviously this does not test the remaining firewall-forward lines or the fuel tank (which gets the balloon test later.) Bill_H.
 
Test pressure

I was not able to find a data sheet for the Facet fuel pump on the internet so was reluctant to use a test pressure for the fuel line system that was more than 2X the working pressure of the pump. The pump does not have a diaphram and probably is not easily damaged, but could be a concern when using a higher pressure to test for leakage.

Tony
 
Gauge and valve

Tony,

I'd like to purchase the gauge and Schroeder fitting you show in your picture. Where did you find these?

Thanks and regards,

Rafael

RV12 Installing Fuel System
RV8A Flying
 
Rapael,
The pressure gauge, brass tee, and Schrader valve were just hardware store items I found at my local Mcclendon/Ace hardware store. The blue aluminum aircraft fittings to connect to the aircraft piping I ordered from Aircraft Spruce.

Tony
 
Thanks to all who responded to my call for assistance. You all were a big help, no doubt. The pictures from Tony w/explanations were especially helpful.
That, plus my neighbor and friend, Jake (who knows all and can build any airplane)
saved the day. Now I have to do the return line.
(I didn't do the hose connection)

Thanks again.
 
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