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Just another Dumb smoke question...

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Just another Dumb smoke question...

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Old 05-28-2013, 12:42 PM
  #1  
Lil Hoss
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Default Just another Dumb smoke question...

This really has me puzzled......
I have a Tams smoke pump with stainless nozzels.
The 2 nozzels are about a 1/2 behind the turbine just off center.
I taxi out to the runway, hit the smoke and it smokes like it's on fire. Looks good
Than I take off as soon as I lift off I loose the smoke. Even flying around I have no smoke.
Come in for a landing and taxing back I get smoke???????
I think these are questions that will be ask.......
Yes the smoke tank is full
yes the clunk in the tank is connected. Reason I no is I drain out the tank after flying.
Yes battery is charged. Before I even start the turbine I hit the switch for the pump and the fluid runs out.
It kind of seems that at full throttle I loose the smoke........
I do not have the smoke mixed with the throttle.......
Any suggestions guys???

Thanks

Hoss
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Old 05-28-2013, 12:54 PM
  #2  
smchale
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Default RE: Just another Dumb smoke question...

Hoss,
Can you get your injectors bent in more toward the center of the tailcone?
Do you have a lot of space around the outside of the turbine? Ie. is a lot of your inlet air bypassing the turbine? It may be that in the ground there is very little air moving through the tail so the injected oil gets right not the turbine hot exhaust, but as more air is rushing around the outside its not letting as much of the oil inject into the hot exhaust.
Old 05-28-2013, 02:08 PM
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Jetpilot24
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Default RE: Just another Dumb smoke question...

Put a check valve in line between the smoke pump and the injectors. I had the same issue and found that the pressure from the engine was pushing the smoke oil back past the pump causing the pump to loose its prime.
Old 05-28-2013, 06:18 PM
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Wayne22
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Default RE: Just another Dumb smoke question...

Sean hit the nail on the head....get your injectors right into the exhaust eflux. At low taxi speed, the bypass air and the exhaust velocity is minimal and the hot gas will expand outwards where your nozzles are currently located, giving you visible smoke. At high speed (in flight) the hot exhaust goes whizzing by without ever reaching your smoke nozzles, so no visible smoke. Bend them down about half way between the center and outer cone of your engines exhaust.

Also, it is generally not a great idea to turn the smoke on when on the ground at low speed. It can ignite, and on a boomer, that is a bad thing.........
Old 05-29-2013, 03:15 AM
  #5  
basimpsn
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Default RE: Just another Dumb smoke question...

What happen at full throttle with smoke on during ground testing ?? should get the same result in the air.

P.S first time using smoke and love it
https://www.youtube.com/watch?v=nU7wG_4mLrE

My Opinion.
Old 05-29-2013, 02:38 PM
  #6  
Dustflyer
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Default RE: Just another Dumb smoke question...

Put the injectors directly into the exhaust flow. For the best smoke, use Tamjet's Ultra Spray nozzles. Here's how it should look and some picture of the smoke it produces at max flow rate:

If you would like to see it in action, go to 1:30 on this video. I am using a Tamjets smoke pump with a Simjet 1200 on a Super Reaper. Believe it or not, my flow rate is set to half in the video! I plan to back it off some more.
https://www.youtube.com/watch?v=QDuD2G4mcuY
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Old 05-30-2013, 04:48 AM
  #7  
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Default RE: Just another Dumb smoke question...

Three things

Check valve
Bend sticks into flow
Open up the gap around your engine so it won't pull air in from the back at full throttle. Need an inch air gap around motor

I get plenty smoke out of one stick and the system pressure is higher. Personal pref

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