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Old May 02, 2005, 12:21 PM
nexxa is offline
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Montreal, Qc, Canada
Joined Oct 2003
106 Posts
Experience with Smoke System

Excuse my English! (I’m French)
I spend a lot of time on forum, searching for smoke system for small engine (.40) and I found nothing. I would something easy to install, tune and a lot of smoke. On big engine like gas, it’s easy (more than a small), but with a small engine there are many problems…. Like not enough heat, the smallest pump delivered too much oil, market smoke injector to big….

I decide to equip my Hangar 9 Arrestee .40 plane with a smoke system. Just for the fun. I fly this plane 1 year without, with different prop, must of time with a 10X7 for speed on 30% nitro gas. I prefer speed to pattern...
Now I equip it with a 12.75X3.25 prop and add my smoke system in it. All modification add 1.2 pound to the plane (oil tank, tubing, pump, extra batteries, muffler modification) Ready to fly weight is 7 pound now! But with this prop, this not a problem!

Firt, I install everything like the pump manual explains.... I only put a smoke injector on the muffler. Result.... Bad! Not enough smoke, the pump running to its minimal rate delivered to much oil... not enough restriction on the injector, and the oil arrive in the muffler to cold.

The second version, I install 12" copper tubing in the muffler to preheat the oil and make the output hole very small. I squeeze the end of the tubing with pliers... to reduce the amount of oil and mount the pressure in the oil line. Yes the pump speed can be reduce or increase by the transmitter, but at minimum speed, it still delivered too much oil. But it's working better. Now I can tell I have a smoke system, but not suffisant for the time I spend to install the system. The 4oz oil tank takes 3 minutes to be empty...

But I was not satisfied enough. I need to preheat the oil more, and I need to increase the pressure in the line to make possible to increase or decrease by the transmitter the pump speed.

I make a third version! (time to loose!). I buy a 36" copper tubing and make a lot of spiral with it. I squeeze the last inch of the tubing with pliers to be sure it takes a lot of pressure to make the oil come out. The pump I’m using is very powerful!
I try my new setup yesterday... Not bad, but it could be better. Too much oil... when the pump and all the tubing are primed, I need to reduce the pump rate to minimal... TOO MUCH OIL! It takes 5 minutes to empty the oil tanks and it supposes to take about 8 to 9 minutes when everything is tune perfectly.

The only thing is missing on my system is a regulation valve on the output line. I already buy it, and plan to test it next weekend....

To be continued… If somebody already install and test a smoke system on a small engine like .46 and less…. Let me know!

Some picks and one small video....
Small Video 1 min
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