Hi all, I have been looking in the forum from quite a while, but now I have to ask a question. I have a juwel 34 stove, that I bought last year. It was working fine up until last month. I have used it for quite long- maybe an hour or even more, almost continuously. As soon as the petrok inside the tank finished, I just waited for it to get a bit cool to fill it up and start it again. But after using it like that for couple of days it just stopped starting. i mean, i heated the brass piece with a torch and when i turn the valve on, i can hear the gas coming out, and when i try to engage it, the jet starts only as long as the flame from the torch is hitting the crown. As soon as I move, the jet disappears and I can only hear the gas coming out, but no flame. What could the reason be. I have heated it for longer than 5 mins with no results, which time should be enough to reach operating temps. Last time it did engaged, but the jet was like a normal flame, no power or anything.
If you let the stove burn the fuel completely it is possible the wick is damaged. Disassemble the burner and inspect the wick.
To be honest, I did remove the wick some time ago, to clean the tank, and the wick was not in good condition. But as I couldnt find a wick localy, I used the old original one. I will run the fuel completely and inspect it then. But can a bad wick cause such a problem? I mean the gasoline inside turns into gas, and comes out from the fuse, but it cannot get into operating mode.
If I understand you correctly, you preheated the burner with a gas-flame. (The word "torch" can mean several different things.) This can be too much heath for the burner, carbonise the wick and make it insufficient. If the wick can not transport enough fuel to the burner head, the vaporizing capacity is too little. Check the wick and preheat with spirits. Regards Radler
Hi, i tried with spirits, but no luck. Wick is not in perfect condition, but it also doesn't look worse than it was couple of months ago, when the burner worked OK. I made a DIY wick using cotton balls. but still same. I am starting thinking that it might be the valve, as when i put the torch flame over it, it starts burning with a flame. So I am guessing the valve might be the reason, or am I wrong? PS where can I buy new wick from?
There is a small private seller in Germany who sells the original parts: https://m.ebay-kleinanzeigen.de/s-anzeige/brenner-fuer-juwel-34-barthel-kocher/926379706-230-3823 Last time I talked with him - 1 x original complete new burner with bell, regulator, jet and wick was 15€ A new wick was 1.5€ (plus postage)
Have forgotten about the stove for some time. So far, what I done- i disassembled the burner and took the valve needle out. Cleaned it with fine sandpaper and put it back. As I did not have original graphite sealant kit, I did DIY with pencil and oil. It looks like it worked, as when i heat the burner it did came into working mode, but just for one time. next time it did not wanted to engage. I could hear the gasoline fumes coming out, and when flame put over th bell, the jet starts, but as long as I move the lighter away, the jet stops. Not sure what else can i do, except ordering that new parts, that Harder Soerensen suggested
Sounds like pressure is being built, issue may be the wick, not enough vapor is coming out to ignite and/or sustain a flame. A too tightly stuffed wick or one not able to "move" fuel to maintain or allow a robust flame seems would be the issue. Sometimes a clogged jet/nipple will show same symtoms. Also make sure you are leaving space in the fount to be able to pressurize it. I've had to play with wick position on a few different stoves, one was a recent Juwel I acquired, I thought its flame should be more robust, wick wasn't bad, but I thought it was too tight in the vaporizer tube. Duane
Sounds like a classic case of an ineffective/charred wick. Definitely worth replacing Never run a Petrol/Naptha stove dry, and use a blowtorch for preheating VERY delicately, remember just a few flames from naptha or meths is usually enough, a blowtorch is many magnitudes more powerful. HERE are some tips Alec.
To be honest, I did ran it out of fuel once or twice, exactly before this happened. So, this might be the problem. Will try to get a new wick, and report to you soon. BTW how should I use the blow torch to heat it up- as what I do is put it on max. and then keep heating the burner for about a minute or more. Or should I do it on low flame?
The depression at the base of the vaporizer is for priming fuel such as denatured alcohol/meths/stove fuel. A torch is over kill, if the stove won't get pressurized without that extreme heat, something is wrong. If operated in cold temperatures, try a double prime or add priming fuel before the first goes out. Duane
Stove fuel or gasoline is ok, just leaves black soot. Some dip fuel from the fount to use to prime the stove or try warming the fount with hands or body heat to force fuel out the nipple with valve momentarily opened. If you care to get some meths/denatured alcohol to carry with you, that would be the cleanest. Duane
Hi all, few months passed, but still nothing. I couldnt get an original wick for the stove, so made one my self. I used some cotton rope, about 2-3mm in diameter, and built a wick out of 3 piece wrapped together with thin copper wire. The Stove did get pressurized, as I could hear the pressurized fuel coming out of the nozzle, but again- once I try to prime, it only start for as long as the lighter is next to crown, once I move the lighter away, it goes of, but the pressurized gasoline still coming out of nozzle. Is the wick no good, or I made it too thick. How thick should one be. Also, I can see some gasoline coming out of the valve once pressure is built, but will try to mix pencil graphite and grease, as I cannot find original graphite wrap for the valve.
@mybabybook , the wick should be a good fit in the tube, it shouldn't fall out but you shouldn't have to use great force to put it in place, just a nice light smooth fit. If you have gasoline coming out of the nozzle, it hasn't been pre-heated enough, it should be vapour before you try to light it. It's an unusual problem. However, I must ask, do you have a flame-spreader fitted? The flat brass plate that sits across/on-top of the burner bell/cup? Alec. Edit: This photo of Tony Press' J34 from THIS thread shows the flame spreader in action..
Hi, yes, I do have one fitted. To be honest, last time when it worked, the flame was coming ok from one side, and on the other, it was just a small jet, much smaller than what it was on the other. not sure if has to do with the flame spreader at all. I did order some graphite sealant that should come in a few weeks as ordered from China, and will than open and clean the valve, put new graphite sealant on it and will use gauze as a wick, as it seems I cannot find any. will report back. To be honest I also think it is an unusual problem and slowly I am getting desperate about being able to fix it.
@Trojandog is able to supply thin graphite sheet. You can cut a strip and roll it around the valve spindle to make up replacement valve packing. Worth contacting to see if he can send to Bulgaria? Alec.
Thanks guys. I will try with the graphite sealant I ordered, once it arrives, and if no joy, I will check with him. I will again disassemble the valve and clean the needle with fine sanding paper like 500-800 grit.
