How to Build Smoke Exhaust System on Yor RC Air Plane

you need to try baby oil

Not at first. It got better when I got the heat insulating tape over the tubing.

did that give a little more smoke by making the fluid going around the head a couple times

It worked, if you see my number II test you'll see smoke amount is pretty decent, it's a bit hard to see due to sun went down =), I think today it's going to be the fight test. Thanks!!, if weren't for your video I Wouldn't started with this project

well, I took my chances and dirlled the crankcase, and guess what, it produces pressure! after installing the fitting and closing the engine (the hard part was to select a spot to drill away from moving parts)I connected a silicon hose and turn the prop by hand and there was air (a fair ammmount) blowing thru the hose, I went to sleep happy hehe, I will continue today, I'm sure it will work! may be a check valve will help to maintain the pressure in the tank, like a YS engine fueling system does

I got the response from Dubro, seems that the problems is that 4 cycle engines don't generate enough pressure to make the smoke fluid flow to the exhaust, think I'm going to need a pump

I found the kit at a local hobby store, but when read the back label instructions saw a note "this product wont work on 4cicle engines". I sent a note to dubro asking them why, if it's because the cranckcase pressure o the exhaust temperature, I'd like to figure out because I really want my Piper Cub with the Saito to smoke, I am waiting for dubro to respond., by the way the kit comes as you showed in your video, valve,tubing, and fittings.

Partumber is DUB255. costs $10.99 at towerhobbies. Its not a comlete kit.
You'll need to add a Oil/gassoline proof tank, and a servo.
Remember, dont use nitro silicone tubing in the oil system at all. It will dissolve.
(also the one inside the tank)
The kit comes with the black heat resistant Neoprene hose. Use that.
You can also use yellow Tygon hose, but it's not that heat resistant. Use fuel line clips to avoid mess...
I'll think your Saito.72 will do better than mine.

hi, I found the product at dubro page, but it does not seem to be a smoke kit, they seem to sell valve, fittings and tubing separatelly. what is the dubro part number for the kit you bought?, I'd like to put the system on a Saito .72, do you think it will work?
Thanks

i have an idea of pressiuring a metal tank with somthing of a bike pump, and then using a servo to regulate te fluid flow.

I tried smog machine fluid, but then the engine RPM drops by 1500 rpm and then there is even less ''normal'' smoke.

Have not tried it yet. But I think it would do good. The fog machine liquid seems to be waterbased and made of Glycerol and glycol.

But on some web pages they say the oil based is more persistent than waterbased.
An oil based is ViCount.

what if you used fog machine liquid i know that heat causes it to turn from liquid to fog and a little goes a long way

I did not doit like you.

I have oil tank pressure from exhaust. I didn't want to drill in to motor. It's easyer to replace exhaust if something went wrong.

Engine runs fine with smoke on.
Yes, the engine rpm drops a bit. not much.
It's caused by the exhaust backpreassure like you mentioned. (it's the same with a Skywriter pump)
There is no negative effect using the crankcase preassure.
To much or to little oil will decrease smoke effect. Anyway, the two stroke engine hasn't the optimal exhaust temperature.

did the engine run just as good as before?
couse youre increasing the vollume of the crankcase with the pipe to the tank.
also youre changing the densety of the exhoust gasses when your injecting extra fluid in the exhoust, this may couse additional back pressiure.
I could be wrong, i havn't studied to make smoke systems.
I tried it with diesel injection at the same place you do, but i only got about 20% more smoke and a RPM drop of 300rpm