How deep is the charcoal that air is penetrating into and out the other side of the charcoal on the grate side? Burning moist charcoal up to 15 % should be no problem.
A white smoke, might be seeing steam in the smoke. I would using drier charcoal for your gasifier. A thick oil vapor could be white also.
Bob
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Hi Bob
from the tip of the nozzle to the grid there is 9"
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thierry, make a try without oil, than you see from where the smoke comes…
maybee the reduction area is too short…the glow under the nozzle will shure occupie 5 inch or more, depends on air flow and than for reduction remains not much
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I agree remove the oil and see what happens. Easy first step here. If you get a flare you know it was the oil.
Bob
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What happens when you pour oil on charcoal? I tried this on my tractor and expected it to produce rich gas, but alas, only white smoke came out, which did not want to burn, and the gasifier needed a much longer start-up time. It is likely that the oil would enrich the gas if it were added after the gasifier is well warmed up, but not at the beginning. Oil has a high boiling point and requires a lot of energy for gasification, and then takes a lot of energy from the coal during reduction.
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thanks for the tips and info guys. Giorgio and Bob my nozzle is cooled by the oil bath. I can’t test without oil without risking destroying the nozzle.
Tone, interesting info for me, “only white smoke came out, which didn’t want to burn,” that’s exactly what happened on my last test
I tested again today with new carbon. I got a flame after several tries… finally a little hope.
I believe that the oil vapors will condense on the charcoal when the gasifier cools after working. Restarting the gasifier releases a lot of white vapor. I will have to send the vapors into the air inlet of the gasifier.Or also abandon the oil bath nozzle
Thierry
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Can you put water in it instead of oil. I know the water will boil off unless you keep replentishing it but at least you will know if the oil is causing the problems. Water vapor will help with dry charcoal.
Bob
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Bob I’m pretty convinced the white smoke is from oil vapor. I don’t want to build a water cooled nozzle because here the thermometer is below 0 at least 6 months out of the year 
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thierry, ash water not freezes immediately, i dont know how much under zero remains liquid…maybee coolant for your nozzle??? my son used it as electrolyt and has observed that not freezes in winter…
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what do you mean by “ash water”?
take a half bucket with ash( we have hard wood ash) and fill the bucket completely with water… mix it with a stick from time to time, after some days is ready, let settle the ash down and take away the liquid…this is a lye…we use it for dirty from oil or grease hand-washing…it stands always outside never seen frozen, of course we have never so much degree under zero as in your place…try it out how much under zero (celsius) it remains liquid- would be interesting…for our motorcultivator gasifier we will make a water-cooled nozzle like gohin-poulenc or the design from chuck whitlock (forum member here) and use this ash lye for coolant against frost…but i think components must be in stainless steel .but i dont know if the structure of the ash water changes with heat…
a solution for you can also be using the antifreezer from car, in a closen circuit, but for this the nozzle design of chuck will be better, as a verical nozzle, because it makes the coolant draft by thermosyphon-physically…
why you use a vertical nozzle from top? what advantage you see with this nozzle?
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thanks Giorgio for the info
I use a vertical nozzle for 3 main reasons
1: it allows me to modify the distance between the nozzle and the grid, by sliding it from bottom to top.
2: it allows me to easily see the color of the flame
3: it seems easier to build than a ring of nozzles
PS: I decreased to 8" (9" before) the distance from the grid to the nozzle and the gas is lit quite easily. I guess the oil vapors bypassed the hot zone (the nozzle being too far from the restriction)
the gas and the bottom of the gasifier remained surprisingly cool. (the vapors no longer mix with the gas and therefore no longer heat it)
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