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NEEDLE VALVE basics 101

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NEEDLE VALVE basics 101

Old 06-14-2009, 08:38 AM
  #1  
tony0707
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Default NEEDLE VALVE basics 101

hi a glo n/v is a tappered needle and seat design-so never turn it hard the last turn in- do it ever so slow and gentlyhave you ever taken the time to study the nv tapper with a loop (jewelers glass ) you will be amazed at how rough some areyou can use 600 emory to polish them you will experience a new smoothness to the engines performance- this applies to the top end nv mostlynot all nv from the same manufacturer are created equally-so find a good one-if you jam your nv into its seat you will create a ridge in it that will reduce its performance-the glo fuel flows over
whenever you choose to remove a nvalways turn it intothe seat -count the revolutions- you can now return it to the place it was-were the engine was running as it s/b- you do not have to go through the whole tune up process again -that can be a bit timely- mark the nv -so you always know its location-with a dremel-or install a marker-i use old allen keys on my OSengines-hope this helps some a bit REGARDS TONY
Old 07-04-2009, 06:44 PM
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TexasAirBoss
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Default RE: NEEDLE VALVE basics 101

Wowth at is so mereall y great advice, but ifyou don't use punctuationor spaces, its difficultto rea d.
Old 07-04-2009, 09:45 PM
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42etus
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Default RE: NEEDLE VALVE basics 101

No kidding. You don't take the time to make your posts readable by others, yet you expect a response.??? I may or may not be able to help you, but I won't bother trying to decipher your message.
Old 07-04-2009, 09:56 PM
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larrysogla
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Default RE: NEEDLE VALVE basics 101

tony0707 was offering some really good advice................but his grammar needs some tuning from the English class. 'Nuff said.
larry
Old 07-11-2009, 01:27 PM
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rpaulflyer
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Default RE: NEEDLE VALVE basics 101

I have a question regarding a needle valve on a os 61 max. I need to extend it out about 2" to fit the cowl opening on a super steerman plane. What I have on the engine right now is a 90 bend rod that is too short for this cowl. Need some ideas. Thanks Rick Flyer.
Old 07-11-2009, 05:39 PM
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da Rock
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Default RE: NEEDLE VALVE basics 101


ORIGINAL: rpaulflyer

I have a question regarding a needle valve on a os 61 max. I need to extend it out about 2'' to fit the cowl opening on a super steerman plane. What I have on the engine right now is a 90 bend rod that is too short for this cowl. Need some ideas. Thanks Rick Flyer.

Most OS engines' needle valve bodies have a hole in them with a gib screw to grip a braided wire extension. They also provide the wire and a collet to make the extension from. Need more length? Use a longer piece of braided wire. Where to find the wire? Some pushrod systems are a braided wire in a tube. You can find 'em in most LHSs.
Old 07-27-2009, 12:36 PM
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MadScientist
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Default RE: NEEDLE VALVE basics 101

That post hurts my eyes to read it.
Old 07-27-2009, 01:50 PM
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anuthabubba
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Default RE: NEEDLE VALVE basics 101

rpaulflyer,

A long extension adds a vibratiing weight to the N/V and can cause damage to the N/V seat. If you secure a small Allen head screw in the needle valve end (may have to drill it out some) it can be reached with a ball driver through a small hole in the cowl. Nothing hanging out. Have used this arrangement many times.

Terry in LP
Old 08-01-2009, 04:28 AM
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jaka
 
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Default RE: NEEDLE VALVE basics 101

Hi!
A much better way than extending the needle (Which is not a good to do it) is to mount a second needle (another needle) more conveniently.
The problem with extensions is that they will vibrate up the needle seating which will render the needle useless in a short time.
Also an ugly hole has to be taken up in the engine cowl...
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Old 08-01-2009, 06:10 AM
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da Rock
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Default RE: NEEDLE VALVE basics 101

Most of the needle valves on the engines I'm using (from .40 to .90) are designs with well supported needles. The threaded length is decently long. Further there is an o-ring seal that supports well, and there is also a ratchet that stabilizes and supports. I've had to rebuild two engines in the last year. They get flown a couple of times a week, least case. And the "new" one is at least 3 years old. They both have extensions. One is a solid piece of piano wire. The other is a longer braided wire with the collar at the end. I guess the wear would depend on the design of the needle body and maybe another important detail. Every prop that gets bolted on is checked for balance and balanced if needed. And the OS needle designs nowadays is as described and decently robust as well.

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