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Author Topic: Cox reed needles  (Read 3613 times)

Offline Bootlegger

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Cox reed needles
« on: November 06, 2015, 12:06:18 PM »

 Are their an differences in the reed needles in the Cox engines with tank? The reason for this question is I have a couple of the reed engines that the needle as lost over the years I ordered replacement needles (short) and they will not close down enough to be able to get the engine to run.

  Any help will be appreciated...

  Oh, what is the thread size for these needles?
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Offline Chancey Chorney

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Re: Cox reed needles
« Reply #1 on: November 06, 2015, 02:44:40 PM »
I am in no means an expert, but it sounds like you lost the needles a while ago. If so, could it be a possibility that the threads in the backplate are dirty and require a good cleaning? Just a quick thought here.
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Offline Bill Adair

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Re: Cox reed needles
« Reply #2 on: November 06, 2015, 05:19:41 PM »
Gil, Chancey,

No expert here either, but I know of three different needles for the Cox .049/051/.09 series of engines.

1. The reed Babe Bee type .049/.051 engines, with round tanks.

2. The reed product type engines, with square back plates.

3. The .049, .051, and .09 Medallion engines.

Wouldn't it be nice if someone (Hi Bernie?  ;D) made a needle valve conversion chart, with thread pitch and diameter, plus Cox part numbers?

Then there are the aftermarket fine pitch needle/spraybars like KirnKraft, and others. It's a virtual quagmire of choices, but Bernie probably has a needle that will work for most of them, and his prices are very reasonable!

Bill
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Offline Chancey Chorney

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Re: Cox reed needles
« Reply #3 on: November 06, 2015, 06:33:56 PM »
Hi Bill. I do believe that we are on the same wavelength. He mentioned Cox engines with tank. I too was about to make mention of the possibility of a fine thread needle, but I believe that they were available/only came on the postage stamp engines and a few with the horseshoe backplate. I could be wrong. A chart would definitely be helpful, and informative.
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Offline Phil Krankowski

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Re: Cox reed needles
« Reply #4 on: November 06, 2015, 06:56:47 PM »
I am not aware of a tank back using a fine needle except with a insert, which makes it look pretty obvious.  (I don't remember who made the inserts, I never had one)  The short needle should fit just fine, the long needles will extend past the cylinder of a bee tank engine, which is not good.  As far as I know the thread is the same.  If you have one of each needle then flip them around and lay the threads on each other and you can immediately tell if the pitch is different.

if all else fails

coxengines.ca
exmodelengines.com

if you have a fine pitch then you will be limited in choices.  I do not believe either company has fine pitch needles. 

texastimers.com has fine pitch, but I know for a fact that their pitch is not the only one used as I have 2 fine TD NVA's that have different thread pitches.  One is a TT, the other is unknown.

Phil
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Offline Bill Adair

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Re: Cox reed needles
« Reply #5 on: November 06, 2015, 07:40:04 PM »
Phil,

A few years ago I picked up a TD with a KK needle valve, but the needle that came in the box with the engine would not fit, nor could I find one that did fit! The needles from Texas Timers would not fit either, though Ed says they are from KK. Don't remember what I did with that TD, but it may still be around here some where.

Anyway, I may have run into the same problem you had with your 2 different TD NVAs.

Bill
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Offline Phil Krankowski

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Re: Cox reed needles
« Reply #6 on: November 06, 2015, 08:08:46 PM »
Quote from: Bill Adair on November 06, 2015, 07:40:04 PM
Phil,

A few years ago I picked up a TD with a KK needle valve, but the needle that came in the box with the engine would not fit, nor could I find one that did fit! The needles from Texas Timers would not fit either, though Ed says they are from KK. Don't remember what I did with that TD, but it may still be around here some where.

Anyway, I may have run into the same problem you had with your 2 different TD NVAs.

Bill

Glad I am not alone on this.  The oddball nva came on the used engine so no history at all on it.  I have a few TT NVA's for both TDs and for the back plates.  At least those are interchangeable needles!  (they say the non-TD nva is not for the reed engine, but it went into a cox back like it was made for the job.)

Phil
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Online kenneth cook

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Re: Cox reed needles
« Reply #7 on: November 15, 2015, 03:58:29 AM »
                If it screws in, it's correct. A fine threaded 128 won't screw into the 80 tpi without forcing it. Stock needles for integral tank bees can break the point off inside. Does it screw in? If it's not screwing in enough there certainly is a good possibility that the point of a possible older one is broken off inside.

             The KK needle and the Cox postage stamp needle are one in the same. Cox makes two types of needles that were used in the postage stamp and horsehoe backplates. I use a KK spraybar to always verify as they're the 128 TPI needles. You can interchange the two as I do frequently due to them getting damaged from a crash. The two needles look the same but they're not. The 128 TPI in my experience never had a knob of any kind on the top. The other I believe is a 80 TPI threaded needle. That particular needle will fit a stock TD spraybar but the tapered end is different and I can't comment on whether it works or not. I do know it screws in.
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Offline Mark Mc

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Re: Cox reed needles
« Reply #8 on: November 15, 2015, 12:53:22 PM »
Just looking at it sideways here.  You say it won't close enough to run, as in it's too rich.  Are you sure it's the needle valve?  Have you checked the venturi gasket inside the tank?

Mark
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Offline Daryll White

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Re: Cox reed needles
« Reply #9 on: November 15, 2015, 05:51:02 PM »
Bootlegger,I was in a similar situation,ordered a new reed needle for one of my older reedies and it would not screw down all the way.I then took one from my older  Babe Bees and it worked fine.I have found that the tolerances in some of the newer manufactured parts are not as close as OEM parts.My suggestion get some used Bees on the bay and use them as parts engines.
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