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sparkplugs
#21
OR SAILBOATS!!!!!!!
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#22
turboeddie - 6/1/2011 7:28 PM

OR SAILBOATS!!!!!!!

Nice....

Looks like a Hunter, but hard to tell from this angle.

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#23
Holy crap TurboEddie! I'd venture to guess that you have at least $300.00 tied up in that sailboat! Would dearly love to go out on one someday! They say you never forget the sensation.
Rob2
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#24
Speaking of sparkplugs, has anyone tried E3's in a mosquito yet? I know they make them for just about everything imaginable, so I'm sure there's one to fit. Of course, what do I know? I'm just a car guy dreaming of the open skys lol.
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#25
Knock, knock, who's there? It's Dave, let me in man. Dave's not here.
OK Skeeter I bought the $8 fancy Iridium magic plugs, it's a sunny day so I thought I'll put 'em in.
When I removed my NEW old standard plugs that have run for less than one hour - they are black. I'm running 50:1 TTS, my Bing mid-range needles are set for max rich. I think my other jets are what everyone else is using. Temps are very normal 315-340 and 1100-1200 if I remember right. Should I go as-is with the Iridium's or lean down the mid-range? What Bing setting do you have? Rob1?, Rob2? Rob3? Thanks.
-larry,
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#26
I'm using 165 mains, the needle jets that came with the thing, needles in highest position. My plugs get black too, pretty quick. My EGT's are runniing around 1100, CHT's 325/350. I really don't know why I can't get good looking plugs, temps appear to be good.
Skeeter
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#27
Skeeter - 10/19/2011 3:32 PM
... needles in highest position.
Skeeter

As in the keeper clip is in highest slot of needle (leanest)? -thanks Dave, -larry,
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#28
Pfranc - 10/19/2011 9:02 PM

Skeeter - 10/19/2011 3:32 PM
... needles in highest position.
Skeeter

As in the keeper clip is in highest slot of needle (leanest)? -thanks Dave, -larry,
No, lowest clip position, or my EGTs spike in decent.
Skeeter
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#29
Hey fellas,
I would like to humbly add my lessons learned using the Bing 54's in a helicopter, in flight.
First I'll start with a few facts that everyone will agree on:
* After a couple of hours, your plugs should look slightly tan with some black (not soot or oil foul or carbon buildup)
* Your EGT's should be where the factory says, If they are low or especially high, FIX IT.
* A 2-stroke needs to operate at a hot enough temperature so as to not gum-up the ring grooves.
Second I'll touch on how to use plug color and in-flight EGT behavior to tell WHICH JETS ARE not correct.
* IDLE JETS are EASY. If your RPM is constant while the engine is idling for a several minute period on the ground, they are right! If RPM is decreasing (loading up) they are too rich. If RPM is increasing with time, they are too lean.
* MAIN JETS ARE EASY. While you are flying at a safe altitude and enter a FULL THROTTLE climb with MAX PITCH the rotor blades will take without RPM dropping, observe EGT's and jet for factory spec temperature. If your EGT's are lower than the factory target, FIX IT because your engine will reward you with more power, less gumming up. If your EGT's are higher than factory target, FIX IT because you are risking siezing yor engine.

NOW THE NEEDLE-JET AND JET-NEEDLE PAIR IS THE COMPLEX, CONFUSING ONES, AND UNFORTUNATELY THE MOSQUITO IS PROBABLY USING THE NJ/JN TEAM DURING 70% of normal flying, unless you are a BIG guy and cruise-power is above 75% for YOU.

The first thing to understand about NJ/JN jetting is this. Air Volume entering the carburetors is metered by the throat baffles. They are hooked to the throttle, open linearly as you twist the grip, and are full open at one extreme and almost closed at the other extreme. There is no adjustment for them. Air/Fuel Ratios are changed only by varying the Fuel Volume, by jetting.
The second thing to understand is THE NEEDLE JET IS AND OUTSIDE JET, THE JET NEEDLE IS AN INSIDE JET.
The jet-needle is long and skinny and the needle-jet is short, blunt, made out of brass, and rattles around in a confined area and is not connected to anything. The long jet-needle penetrates the needle-jet and the air space between the O.D. of the jet-needle and the I.D. of the needle-jet, meters the fuel into the engine between 25% and 75% throttle opening. +/-.
Bing makes many many jet-needles which have larger/smaller O.D.'s, Different heights where the tapered part starts, and different rates of taper.

When you reach approximately 75% throttle, the air space between the needle jet and jet needle is larger in area than the orifice in the main jet. Beyond that point, the mains are doing the metering and the NJ/JN pair have no affect.

As you can see, if your ship and butt are "average," in weights, you will more than likely be hovering above 75% power and spending time on the main jets. For you fortunate, smart folks that are skinny and don't load up you ship with 50 pounds of avionics, it's possible you may be hovering around on the NJ/JN's, below 75% power. The amount of time you spend hovering vs. cruising around, combined with your takeoff weight, may have something to do with your black or tan plugs?

Now I'm gonna focus on proper jetting of the NJ/JN circuit. It is very complicated and confusing to me, even with my experience because there are 5 variables that interact. Each one has a different effect on the air/fuel ratio. 1) clip position 2) Jet Needle O.D. on the big end 3) how far from the top the jet-needle taper BEGINS 4) the RATE of taper toward the skinny end of the jet-needle 5) I.D. of the needle-jets.

There are very accurate charts in the back of the CPS Catalog that shows graphic plots of all the jet-needle variables to get you in the ballpark. Each needle is shown with a plot of fuel vs. air ratios for the various needles available.

THE REAL INDICATOR OF THE NJ/JN CIRCUIT BEING JETTED CORRECT IS AS FOLLOWS:
If you are cruising around above 75% (on the mains) and begin to lower collective to descend, and your EGT's rise, you need to adjust one of the 5 variables in the NJ/JN circuit. If your EGT's do not increase as you lower the collective to descend but stay near factory spec, you are pretty close. If the EGT's continue to drop as you lower collective to descend and the engine begins to act like it's loading up, you are too rich on the NJ/JN circuit and need to adjust one of the 5 variables.

The goal should be mostly tan/slightly black plugs across all throttle zones, a smooth consistent idle, a good POWERFUL full throttle climb at max pitch, at factory EGT/CHT spec., and a smooth descent engine at factory spec. EGT/CHT that does NOT require constant "clearing" on the way down.

My suggestion is to get the CPS Catalog and STUDY STUDY STUDY The bing 54 Needle-jet/Jet-Needle graphs to grt your PhD. on this complex, 5-Variable circuit. Knowledge is power and ignorance is danger!
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#30
Not sure if this go on the post on jetting or this one - no matter

In the way of for what its worth its my understanding the Bing 54’s on the Mosquito are not "stock" as the throat is different also the jet needle is not listed in the standard replacement parts chart. The stock jet needle size is 8F6Z - the 8 indicates richer mixture above half throttle the F indicates a leaner mixture below half throttle not sure leaner or richer relative to what probably another numbered needle but I couldnt find a reference or elaboration

The numbers on the Bing you present are different from the Pro Carb Shop Tuning and Parts Manual for Bing Carbs, diagram page 11 which offers a very comprehensive “how to” on tuning Bings and is worth the 10 bucks as a reference manual/guide. (procarbshop.com)

There manual show a slightly diffrent range of operation though not significant:
Main jet operation between 60 and 100%,
Needle jet/jet needle between 80 and 15 %
Idle between 25% and 0%

One thing to remember is the carburetor only reacts to air velocity not the weight of the air. The carb will flow the same amount (by weight) of fuel/oil, which is why the mixture becomes richer with altitude, and requires jet changes.

Not sure I understand “The amount of time you spend hovering vs. cruising around, combined with your takeoff weight, may have something to do with your black or tan plugs”. It’s been my understanding that if it hovers it can fly with no appreciable increase in power. The power applied in the hover should be your normal take off and climb power, and in some aircraft taught as the normal take off (no applied power over hover).

Think I've posted this previoulsy, on the mosquito, normally the stock 2.76 mid range needle jet runs hot at flat pitch and require a change to 2.78’s to lower the temps, I've not had a requirement to change the jet needle size, on occasion a clip up or down – the mains require adjustments to meet the altitude stocks are 195 which is usually rich for most applications, think I've got 165 installed and probably not vaired more than 5 either side

Mike
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