I have a cowled engine that really needs 3 fuel lines to fill. How are you running the 3rd line. Are you using a T to come off of the carb inlet line?

Line to the carb, line to the exhaust pressure, and the 3rd/ fill line to a [link=http://www3.towerhobbies.com/cgi-bin/wti0001p?&I=LXD745&P=0]fill valve[/link] ..

If you install the valve into the cowl it will need some liteply or other type of support epoxied onto the backside. This will stop the glass from cracking around the whole you make for the valve.

If you install in the fuse through a piece of 1/8 liteply be sure you do some extra fuel proofing of the area. Sometimes the valves leak a little after you first remove the fill line. Fuel proofing the wood is a must if you choose this option.

Just install the third line into the tank the same way you do the carb line.

On the fill line are you doing it the same as the line going to the carb. i.e,. running a line inside the fuel tank with a clunk on the end?

what they said......

I use 1 line to carb, 1 line from muffler...bent upward inside of tank of course, and the 3 rd line is from a second clunk to a fuel dot....have done this on several airplanes without a problem....

Same here. It is simple and reliable. I tried doign the 3rd line without a second clunk once. Filling was no problem but draining was a pain so I now use the second clunk.

I have had bad luck with the fuel fill valves on the market but I knwo some people like them. I just figure a simpel plug in the 3rd line like a fuel dot is nearly foolproof.

This is all on a typical glow engine of course. On a gasoline engine or glow engine such as a YS with a pump-type sytem I just T into the line coming from the tanl to the fuel inlet.

Main line and vent line as usual, third line with a clunk so you can get all the fuel out of the tank. I have the third line run out through a dot. The dot mounts in the fuse, not the cowl.