now what??
#1
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You can put me on the list of people that hate remote needle valves. These are pictures of the firewall and cowel of a Sig King Kobra that I am building and as you can see I have the engine as far back against the firewall as I can get it. Even with this I still had to extend the cowel aprx .500". With the remote needle valve all the way against the firewall I will not be able to get to the carb line to fuel the plane so I was wondering what other methods would work the best. I thinking of using a 3
line system where I can fuel and defuel form the 3rd line, If I do this do I need to have 2 clunks in my tank? Or is there a better way that I am not seeing.
line system where I can fuel and defuel form the 3rd line, If I do this do I need to have 2 clunks in my tank? Or is there a better way that I am not seeing.
#2
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Use a fuel dot, that way you do not have to disconnect the fuel line at all.
What engine are you putting on that King Kobra? I have always LOVED that plane, and plan on getting a couple of more in the near future.
Would you mind posting pics of your progress?
Thanks
What engine are you putting on that King Kobra? I have always LOVED that plane, and plan on getting a couple of more in the near future.
Would you mind posting pics of your progress?
Thanks
#3
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In case you are not sure, a fuel dot is a 3rd line system.
I use 3rd line systems in all my planes.
Without 2 clunks it requires that you stand the plane on its nose to defuel the tank. (The 3rd line goes to a metal line similar to the vent line, except it goes to the bottom ot the tank at the front of the tank.
I use 2 clunks in my tanks and have not had any problems with them or fueling/defueling.
Another option you may want to consider is to run the fuel line from the tank OUTSIDE the plane, cut it and insert a piece of brass tube about 1 1/2" long and then run the fuel line back into the plane and to the carb on the engine. To fuel/defuel the plane just disconnect the fuel line from the piece of brass tube (and yes, they do sell commercial versions of this ).
I use 3rd line systems in all my planes.
Without 2 clunks it requires that you stand the plane on its nose to defuel the tank. (The 3rd line goes to a metal line similar to the vent line, except it goes to the bottom ot the tank at the front of the tank.
I use 2 clunks in my tanks and have not had any problems with them or fueling/defueling.
Another option you may want to consider is to run the fuel line from the tank OUTSIDE the plane, cut it and insert a piece of brass tube about 1 1/2" long and then run the fuel line back into the plane and to the carb on the engine. To fuel/defuel the plane just disconnect the fuel line from the piece of brass tube (and yes, they do sell commercial versions of this ).
#4
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There is a much better way than using two clunks.
Think about it, a clunk is used so you can draw fuel regardless of the planes orientation (Upright, inverted, etc.) You won't need to de-fuel when the plane is inverted, right?
Just bend the third line down slightly and put a piece of fuel tubing on it. It will stay on the bottom/back of the tank - just where you need it for de-fueling
Think about it, a clunk is used so you can draw fuel regardless of the planes orientation (Upright, inverted, etc.) You won't need to de-fuel when the plane is inverted, right?
Just bend the third line down slightly and put a piece of fuel tubing on it. It will stay on the bottom/back of the tank - just where you need it for de-fueling
#7

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Remote needle valves are a good idea. FIXED remote needle valves are not!
The needle valve on the OS .46 AX can be removed and reconfigured. Works great, keeps your fingers safe and allows you to make it fit the airplane.
The needle valve on the OS .61 AX is a fixed casting and you're stuck with the configuration. I tried shoe horning one into an old airframe and it just wasn't possible without cutting the nose off and rebuilding. I returned it and went with a different engine.
Dave
The needle valve on the OS .46 AX can be removed and reconfigured. Works great, keeps your fingers safe and allows you to make it fit the airplane.
The needle valve on the OS .61 AX is a fixed casting and you're stuck with the configuration. I tried shoe horning one into an old airframe and it just wasn't possible without cutting the nose off and rebuilding. I returned it and went with a different engine.
Dave
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Thanks for every ones advice. I think I will go with three lines the way minnflyer suggested. I actually have not worked on this plane since around Thanksgiving. I clenaed it off my bench to assemble an ARF and have not worked on it since but I made good progress before that. The wing and tail group are complete now I just need the fuse. The elevator stock that came with the kit was of poor quality so I sanded and shapped my own and even routed out some lightning holes while I was at it. Oh, and foam core wings are a hell of a lot more work than they look
. The engine I will be useing is an OS 61 FX
