The worst tank ever + UFO with yellow flames

Last summer I found a tucked away Radius no 5 s:or with ufo burner in a wood shed. Looked terrible and the tank was filled with alcohol (rødsprit). Probably been in the tank for decades. It was a lot of job to clean out the tank. Huge amounts of brown flakes kept coming. Finally it seemed clean, I decoked the burner and it was ready. It works ok, but the flames are very yellow. Tried new jet, still yellow flames even at low power. My guess is that there is something from that mistreated tank that affects the flame. Other thoughts?

 

I have same problem. Initially it had nice, blue flame but not since. I even tried a smaller jet and only had too small of a flame.
Duane

 

Strange, yes my also was bright blue and then turned yellow

 

I tried different caps and they did not help. Your flame is like mine.
Duane

 

And your stove is treated normally and not abused like mine?

I have another Radius, a 21, with ufo that burns just perfect so I got a bit disappointed with this one.

 

That flame will cook fine .

 

When I first fired mine up, it ran fine for a couple times, then started getting yellow in the flame after a short time. I have numerous other Radius stoves and they work fine.
Duane

 

Ed Winskill, you are right, it does not leave soot under a pot. But it is so frustrating when you dont understand why...

 

Hi!
Really nice stove.

I am not an expert.....
I would try do do a more thorough decoking, try to get plenty of air into the burner tubes while they are cherry red hot.

The yellow flames are due to unburnt kerosene getting past the UFO cap.

Just my 5 öre.....

All the best!
Lars

 

Hm, yes you are probably right. I will fire up the Primus blowtorch and the air compressor once more and try. It sounds logical with yellow flame due to uncomplete vaporization

 

Mine ran correctly a few times after acquiring, so don't know why it burned like above pic. Maybe it was border line getting coked up.
Duane

 

Does it burn better if you reduce pressure in the tank?

 

Runs blue for a short while when I start up at low pressure, then yellow no matter what pressure it runs at

 

Same here.
Duane

 

Without a endoscope or some other gadget it is hard to see if there is gunk in the tubes... if the vaporization is not complete it will lead to yellow flames. As a caveat, there might be hundreds of other reasons for yellow flames. So take my suggestion with a bag of salt. I used an old wire on a hand drill to brush as much as I could reach inside the tubes. Besides heat and blowing air that is.

But whatever the result, heating metal until it glows is always rewarding

/Lars

 

But if you heat too much you can damage the burner? How to know what is the right temperature?

 

Below the brazing temp. Obviously.
You just want to burn the combustable. See smoke.

There are old posts of the fixture that was used to heat and blow vaporizers. Much like bicycle pump.

 

My air compressor has a valve that can be adjusted to whatever pressure you want to release. I believe from old posts to use 10 lbs.
You'll likely need new heatproof washers when attaching the burner again.
Duane

 

Gustav Barthel where to start?

 

Thanks guys!