Great-North

I was wondering how guys put the extension on their needle valve when the cowel is on? How do they tighten the set screw for the wire you put in end when the cowel is on? Thanks

RCKen

My Feedback: (9)

Because people have different engine/plane combinations it's a little different for every plane that you have. But here are the basics to get you started. First of all I use music wire for making a needle valve extension. Most all brands of engines will have hole in the needle valve that has a set screw in it for setting an extension in it. Cut a piece of wire long enough to extend back out through the cowl, and then build a 90° angle in it.

One of the biggest problems you will find when doing this is where to position the hole in the cowl. Trust me on this one, if you estimate or "eyeball" it you're going to end up with a huge hole in the cowl. The easy way to do it is to make a drill guide. Reference the attached picture. Cut up a manila folder and get a strip of folder and tape it to your fuselage back behind where the cowl will attach. Use this to locate exactly where the hole in the cowl needs to be. Once you are satisfied with the location then you can put the cowl on the plane, and the guide you have in place will lay over the cowl. Now you can accurately mark where the hole needs to be located.

As far as attaching the extension?? There really isn't an easy way to do it that I've found. What I do is put cowl in place and then put the extension in place through the cowl. You'll have to look through the front of the cowl to see the extension and guide it into the needle valve. Before you put the cowl on turn the needle valve so that the set screw is located towards the front so you can see it from the holes in the front of the cowl. Once you have the extension in place put a long handled allen wrench through the hole in the front of the cowl and use it to tighten the set screw.

Hope this helps

Ken

burgh_guy61

My Feedback: (11)

I make the hole in the cowl just large enough that the needle valve itself will fit. I put the extension wire in tighten set screw then slip it through the cowl and tighten it into the carb. Everything else i do just as Ken has described.

Great-North

Thanks Ken for the help. Till now i have been flying without the cowel which makes things much easier to get at. Now i want the cowel on and some of these little issues pop up. thanks again.

Mark

Cyclic Hardover

My Feedback: (3)

What brand of engine do you have?

Great-North

The engine is a TT pro .46.

daveopam

My Feedback: (9)

I normally make the wire stick out of the cowel a little bit. Maybe 1/4". This way the cowl can be removed with the wire in place. The last plane I did a little different. I drilled and tapped the end of the needle valve and installed a socket head screw. Now I just put the ball driver into the hole to adjust the needle.

David

Mode One

You guys are kidding, about how difficult this is, aren't you?!? Yes, locating the hole in the cowl, so it lines up, is done like Ken's outline. I make this hole large enough so the whole needle valve and extension assembly can be inserted through this hole. I assemble the needle valve and extension, off the engine. When putting the cowl on, remove the needle valve and extension from the engine. Put the cowl on, insert the needle valve and extension through the hole in the cowl and screw the needle valve in. Reverse the order, to remove the cowl. Pretty easy, unless you simply can't live with a hole big enough in your cowl to put the needle assembly through, in which case yes, this is a difficult proposition and I can't help you as I can't stand things made difficult just for esthetic reasons!