cotman

My Feedback: (10)

Instructions in the kit I'm building suggest a 3 line fuel system... 2 vent lines and 1 filling line (see photo). 1) is there any advantage to this system over a 1 vent line. 2) I'm going to use a Du-Bro Fueling Valve because all fittings will be in the cowl. Any suggestions on plumbing will be appreicated. Thanks

DadsToysBG

My Feedback: (35)

Just follow the directions on the fuel valve. It works just fine. Dennis

Dr1Driver

Use a two-line system. Install the filling valve as per directions in the tank-to-carb supply line. Run the tank vent line to the muffler pressure tap.

Dr.1

rclement

My Feedback: (1)

I used to use the Dubro filling valves but found that after time they leak air and lean out the engine. There's a couple of o-rings in them and the constant in - out of the fuel fitting wears them out and makes them leak.
Anyway, an easier way and fool proof way is to use a fuel dot. You end with a three line system and the 3rd one goes to a fuel dot. Works great and doesn't leak. [8D]

pmw

My Feedback: (1)

Cotman,

I've used the three line system for ever. Most of my engines are cowled and I can't get to the lines to fill and de-fuel. I run the third line out the bottom of the cowl and use a plug to seal the line after fueling. If you run the line to the bottom of the tank as shown in your diagram, you can use this line to de-fuel without having to turn the plane over. But, the fuel will run out of the line until you plug it if there's fuel in the tank. I just pinch it with my fingers after fueling until I get the plug in. You can buy plugs at the hobby store or use a large nail cut down to about 1/2 inch length. Don't use a bolt. The fuel will seep out around the threads.

I've never had good luck with a remote fuel valve. They leak and replacing them is a huge problem once the plane is complete.

Good luck,
Paul

cotman

My Feedback: (10)

Tks Paul..sounds good to me. One further question.... normally I use a overflow bottle when fueling my engines, but because muffler and pressure tap is in the cowl, what do u do... just fill til it comes out the muffler or is there another alternative. Thanks... Dick

Gary L.

Dick, thats what I have to do , I just fill till it comes out my bission muffler.
It's pointed down, so no fuel gets in the engine..

camdyson

Or loop the pressure line outside the cown and back in, with a joiner tube on the outside. While filling, pull apart and overflow as normal without flooding the muffler, then rejoin.