stunthanger.com

Engine basics => Engine set up tips => Topic started by: Allen Eshleman on February 23, 2010, 03:59:22 AM

Title: Needle Valve for McCoy 35
Post by: Allen Eshleman on February 23, 2010, 03:59:22 AM

I have several McCoy 35's.  At least one needs a needle valve.  I have on S.T. 51 NVA.  Could I use that?  If so, how? Any special instructions?   What are some other alternatives.   Thanks in advance.

Allen Eshleman

Title: Re: Needle Valve for McCoy 35
Post by: Jim Thomerson on February 23, 2010, 09:58:41 AM

My McCoy 19's have ST NVA's and run to suit me.

Title: Re: Needle Valve for McCoy 35
Post by: john e. holliday on February 23, 2010, 11:20:37 AM

Try the needle valve in the engine.  See if the holes line up in the center of the venturi.  If the spray bar has only one hole, aim it into the venturi and slightly towards the back.  You may have to fit some washers on one side or the other.  May have to try several needle valve assemblies to get one that looks right.  There are several sizes of Super Tiger needle valve assemblies.  OS needle valve assemblies may even work.  Let us know what you come up with.  By the way on spray bars with two holes, like Fox make sure you can't see the holes when looking into the venturi. 

Title: Re: Needle Valve for McCoy 35
Post by: RandySmith on February 23, 2010, 12:51:41 PM

Quote from: Allen Eshleman on February 23, 2010, 03:59:22 AM

I have several McCoy 35's.  At least one needs a needle valve.  I have on S.T. 51 NVA.  Could I use that?  If so, how? Any special instructions?   What are some other alternatives.   Thanks in advance.

Allen Eshleman

Hi
The ST NVA is much thicker than the stock McCoy 35, You can use it but it will make the ventuire area smaller, Or you can use a OS 20 FP NVA  these are closer to the size or the original. You will need to use a silicone sealer if you have to use washers or shims to get the spraybar in the correct position...make sure you have no leaks

Randy

Title: Re: Needle Valve for McCoy 35
Post by: Allen Eshleman on February 27, 2010, 05:09:33 PM

Thanks gentlemen,

           If I use the ST 51 NVA I will lose venturi space.  Does that affect performance? Will the power be the same? How is the hole placed? I am planning on using it for a rehabilitated Flite Streak.  It's one of the newer McCoys with the flames on the casing but it doesn't have much power. It starts easy and I have used it for sport flying.  However, it was on a very heavy old Cosmic Wind.  The Cosmic Wind has done much better with a B-40 that is now broken in and ready for a Nobler.  I haven't gotten around to trying any of your suggestions yet, but since I have the ST NVA, I'm planning to use it.   

Allen Eshleman

Title: Re: Needle Valve for McCoy 35
Post by: john e. holliday on February 28, 2010, 02:59:44 PM

Try is and let us know.  Should get good fuel draw.