Puttin this thing together and this is my first ARF. Does the fuel tank only need 2 lines (pressure and feed) or do i have to install my own vent? Fired up the os 61fx for the first time and when i went to fill it thru the exhaust pressure hose, it shot right thru and out the carb line (both were disconnected btw) on an empty tank. what am i doing wrong? i know the air in the tank has to bleed its way out but the only way i can think of fueling this every time is taking off the spinner, prop and cowl, and pointing the nose straight up. seems like a lotta work to refuel(as compared to my nexstar) do all enclosed cowl planes fuel this way? this is the stock tank that came with it (with 2 lines) and my nexstar has 3 lines. They should make these things a little clearer to noobs like me! PLEASE HELP! Thanks guys-

Cory

Use three lines with an extra clunk and a fuel dot. The extra clunk will allow you to defuel at the end of the flying day.

Fuel through the pressure line connected to the carb.

the fuel inlet line is at the bottom rear of the tank, filling through the muffler pressure fitting will force the fuel into the feed line as you have found out. a three line setup will let the tank vent through the muffler tap line while you fill the tank. I use a three line setup when I have a coweled engine. on an open front type airplane it isn’t necessary just fill through the carburetor line with the muffler line disconnected.

as stated above, the air has to go somewhere so when you fill throught the muffler pressure line it goes out the carb line, i just fill through the carb line with the pressure line disconected so when the fuel shoots out it is full

great now i hafta take the tank out now lol it just seems like a hassle to refuel a cowled airplane. either way- whether you have 3 lines or not- the cowl still has to come off just to take the muffler line off (at least in my case)- its the os .61fx the way the exhaust tap nipple is situated its too tight with the cowl on.[:'(]

You don't have to take the cowl off each time you fuel if you use 3 lines and a fuel dot. You will have to remove it to mount the fuel dot holder.
Mount the fuel dot holder through the side of the cowl, leave enough length in the fueling line so it can be pulled out through the holder. Once the tank is full, plug the line with the dot and push it back through the holder until the plug is seated in the holder. That is the way I have mine set up.

like this?? works great now! took out the tank, repositioned the vent tube in the tank, and got a dubro kwik-fill fitting. its neat cuz wen you plug the specially designed filler in it stops flow to the carb and bypasses to the tank!! thanks for the help guys! posted my arf pics too

Firestone,
When using that filler valve just make sure that it doesn't stick open when you remove the fueling probe. Those have a very bad habit of doing that which will wind up draining your fuel tank. I've completely quit using those fueling valves and now use fuel dots. They're a lot cleaner looking and work a lot better.

Ken

REALLY!? ure scaring me lol i will my friend. any chance that valve pops open during flight from engine vibrations?? i guess ill see how this works and definitely keep that in mind! i dont like surprises lol

Firestone. Another option to the fuel dot or quick fill valve is this pinch line. In the pictures
it is mounted directly after my pump before the needle valve. I don't know where my buddy
got it, but at the pattern competitions it is a lifesaver as I can remove the small line and use it to
fill my tank, then reinstall the small line and start the engine and do a pinch test before flying.
In picture one you can see it close, in pic 2 you will see it right behind the header.

Some people will say it's unsightly but you only have 4 mins at the contest to start the plane
make sure it's tuned. with this little pinch line setup not only is it easy to fill the engine but
a quick pinch makes sure the engine is close on tuning.