I joined this forum a while ago, before even owning a kerosene pressure lamp. I have since picked up a couple, a Petromax that I believe to be from somewhere in the '50s (feel free to correct me) and a Wenzel that I found locally for a good price. While I've haven't posted anything previously, I've been looking around through the many posts and learned a lot. However, I'm now doing some repairs and have some questions before I attempt the 1st light: 1) Is the mixing tube supposed to have a dimple where the clamp holds it, or has someone forced the clamp screw and bent the clamp, causing the dimple? Setting the clamp at the point of the dimple only gives about 13mm of gap from nipple to tube, and if I move the tube and re-tighten the screw, it's going to make another dimple. From what I learned, its supposed to be at least 14mm, right? It may be that the half moon piece between the screw and the tube may be deformed from over torquing. 2) I had a hell of a time getting the pricking tool to pass through the little orifices in parts 221 & 225 of the Rapid Preheater. I finally got the pricking tool to pass through both fuel orifices and both the air orifices. I'm thinking that all the probing may have oversized the nipple as the flame seems to be very high and yellow. I'm really not sure what to expect as this is my first experience with these lanterns. Take a look at the pics and let me know what you think. I played with the pressure, but while the flame changed a bit, it was still real yellow and sooty. TIA
1) there'd be dimple for any new unit. Otherwise, the screw wouldn't be able to hold the J-tube in position. Check, that the J-tube is perfectly assembled straight/vertical with respect to the inner hood. A tilt would affect the air gap distance. Also check, you're using an original vaporizer. If it is from a clone, it might be slightly longer or shorter. That would affect the gap distance too. Also check, that the lower part of the vaporizer is screwed in sufficiently with the original lead washer. If it is not or a thicker than usual washer is being used, it'd position the vaporizer and jet too high up. That'd affect the gap distance too. Anyway, just try to light it up with its current air gap distance. If it works perfectly, just leave it as it is. 2) Check that the two, sometimes three air holes under the rapid preheater outer nozzle/cap are fully cleared. These are very tiny, hardly visible. From my experience, the gas tip or jet cleaning needle is too fat to get through any of the air holes. I used a 0.15mm wire for clearing those.
Hi @Paul R Welcome to the forum! Great advice from @MYN and plenty of other Petromax experts here to assist as needed. I’m always a little unsure with this style of lantern and have found this to be of great help for reference: https://www.eschaefer.de/hobbys/starkl/px-rest.pdf Good luck with your project and please keep us informed of your progress. Regards, Jeremy
1) that is a production mistake in my eye. The point of the screw holding/clamping the small bend metal piece against the J-tube should NOT dent the J-tube. Any denting or distortion of the diameter will cause the well known operating noise. Models that are way more quiet often do not have the adjustment screw in the J-tube. So making them not that noisy. 2) the air holes, 2 or 4, in the rapid base are very small like the jet on top of them they should NOT be pocked through with the normal needle cleaner. I have no actual bore size at hand, maybe a 150cp needle can fit. General any poking device should fit easy if not do not use it. It will damage the bore.
Thanks for the reply. I believe the vaporizer to be original as the jet is stamped "Petromax Germany". However when originally installed it was tightened down to the extent that it squeezed the lead washer almost completely out from under the vaporizer. That might be the 1mm difference in the gap at the top. When I reinstalled with a new washer, I went just a little under a full turn after contacting the washer to align the knob. The pricking tool is about .25mm(.010") and it seemed to go easily through the air holes once, lined up. I only saw 2 opposing air holes. Possibility when there are more than 2 air holes, they are smaller. I'm sure the the air holes are unobstructed, with the nozzle off, a few pumps of air in the fount and turning the lantern on its side, I got 3 streams of fuel shooting out from both the center and the 2 air holes. I was going to try the preheater nozzle off the Wenzel but it seems to be taller and won't align with the shut-off.
@WimVe Thanks for your input. I've worked on many motorcycle carburetors, I'm aware that forcefully probing an orifice can broach it out. I tried soaking, spray carb cleaner and compressed air with no avail, both the tip of the preheater and the nozzle were plugged solid. So the probing was worth at least a try before replacement. I'm wondering if the older type of shut-off lever will work with a current replacement lower preheater and nozzle??? I'd like to retain it as it is correct for the period of lantern.
That will happen if there's too much fuel in the tank. When planning to use the Rapid torch preheater the tank should be no more than 2/3 filled in order to have enough room for the air which is necessary to generate the spray mist.
For the lanterns made after the war you can maintain the lever even when replacing the lower part of the Rapid preheater (Part No. 225) which is screwed into the tank, and which has the tiny orifices which are essential to generate the correct fuel/air ratio. This part can be obtained separately, e. g. from hytta.de here in Germany.
@Martin K. I intentionally made the fuel come out the air holes by turning the lantern on it's side just to verify that there was no obstruction. I'm in the US, is that site available in English?
No unfortunately this site is in German only. You can use a translating machine, or drop them a call or mail (Fon +49 2330-892.894.9 · Fax +49 2330-89.29.500 · stuga@hytta.de) as they speak English fluently.
@Martin K. Thanks, the translator worked. I'll have to order by Email, I don't have overseas long distance on my phone account.
The complete constructionfor adjusting The Petromax J- tube from 1954 is a faulty construction.I prefer the older models with the two-nut center J-tube attachement. This dominorapid lever does not belong on this tank.Only a knee lever rapid fits on it properly.The tank is from 1966,by then this domino rapid lever no longer existed.So that the distance and the angle matches again , this ring was soldered to the base with the introduction of the new rapid lever.
Thanks for your reply and clarification on the date. I was basing the production date on that type of lever. As far as adding the ring to the top of the tank and under the Rapid heater, that would not change the alignment of the lever & seal to the nozzle. To change the alignment, the spacer would have to go just below the lever attachment and above the heater. If you think about it, the heater and all it's associated parts can be completely assembled while out of the heater to check alignment of the seal and heater nozzle.
The rubber seal of the rapidlever must meet the opening of the pre-heater nozzle at an exactly right angle.If this is not quaranteed,it is not really sealed at this point. However,the new 1964 lever(DE1228575) Was slightly lower than the old 1954 lever(DE951204) This height difference was made up for with the soldered ring.
I know you can't see it very well in the picture,but the picture gives you a better understanding of what I mean.
@Paul R The period-correct preheater lever for your lantern would be the newer all metal unit like the one shown on the right in the photo by Reinhard above. The domino-type(left) like the one on your lantern belongs to a Petromax from the 1950s. The rubber shut-off pip of the rapid preheater can harden or crack/partially crumble with age. It might also jeopardize the sealing. I suspect, the central fuel hole of the preheater has been enlarged. Not uncommon. It might have been done long before you even own the lantern. This can happen while clearing it with the cleaning needle. Since you're having a Petromax 829(500hk), the needle should be around 0.23-0.24mm to match the orifice of the jet/gas tip. It is a little too fat for the preheater fuel hole. I have done poking/clearing on a fair number of rapid preheaters for the Petromax 828(300/350hk) and similar clones with the jet cleaning needle. However, the difference is, on mine, the needle was 0.19mm(for the 0.20mm jet orifices). The resultant flames of the preheater torches should still be mainly blue, with at most, a tiny bit of pale yellow at the tips of the flames. It shouldn't soot up the generator or anything that it impinges on. Be aware that the rapid preheaters are the same for both 300/350hk and 500hk lanterns. If a replacement cannot be had, then you can still peen the central hole a little to make it slightly smaller. However, that requires some skills with a small pin-punch. If done right, it'd get the rapid preheater to function almost like new.
@Reinhard Thanks for the pic of the 2 levers. It's helpful figuring out an issue I was having. By installing the newer, shorter lever on my heater you can see by the pic that the alignment would be much worse. There must also be a difference in either the nozzle or heater height between the old and new. The height of the nozzle is .410"(10.4mm), see pic. I'm thinking that the whole preheater assembly must have came out of an earlier lantern. When I got the lantern the sealing nib lined up perfectly with the nozzle. After installing the new nib, it no longer aligned. The brass part of the old nib was a bit shorter than the replacement nib. If you look closely at the 2nd pic you can see where I added a .5mm shim (red arrow)to bring alignment close enough to work. The 3rd pic is of the old nib which measures .165(about .42mm). I didn't measure the new one but I remember it was longer. Concerning the washer upgrade that was added to the tank: You can see by the green arrow that adding anything at this point would not change alignment of the nib to the nozzle. It would just raise the whole heater assembly higher in the lantern.
@MYN Thanks for all this info. While the shorter heater lever would be the correct one, it would not align with this heater/nozzle, it would be way too short. If you look at the pictures in my earlier post, you can see the alignment issue I was having. I think the resolution at this point is just to order and replace the entire heater/lever assembly. It seems to be available from hytta-de. #226. I was looking around for something smaller that the .25mm pricking tool in my garage but the only thing I could was a strand of brass wire and it wasn't stiff enough to actually probe the hole, I hate when that happens. I was actually thinking about peening to try and resize the nozzle, but without something to get it back to the proper size such as a drill bit, it would be tough to get it right. I see that do make a .25mm drill bit though. Maybe I can get a 350/300hk needle when I order parts just to use for probing, or maybe see about getting a proper size drill bit. It's really hard to tell what all has been done through the years to something this old. Drill Bit Size Chart
@Paul R I understand you completely.You are right. I have now looked at my old spare parts and found that there were connection bodies of different lengths for Rapid lever.However ,it does not explaine why this ring was installed as standard when the new lever (1964)was introduced .
NO WAY ! 250hk is plenty big enough. Alternatively, part number 180 - Cleaning needle for preheater. Cleaning needle for RAPID pre-heater device-part#180 You'll find that most Britelyte spare parts / consumables are compatible with your Petromax. Up to you of course but you could save on shipping by buying "at home."
@Henry Plews I have that tool, it's what I used and the preheater is now over fueling. Of course the nozzle/heater tip may have been previously damaged. That tool is about .25mm. I can't seem to find anything is all of my junk that would be a bit smaller and stiff enough, I thought thinner needle would fit the bill. I've looked at the Britelyt site. I was wondering about the compatibility but seems most stuff will work. I also Emailed STUGA-CABAÑA 2022: Der faire Internetshop mit über 20 Jahren Tradition. HYTTA.DE Petroleumlampen - Petroleum - Eisenwaren - Haushaltswaren and they said that they don't ship to the USA. The parts from Britelyt are considerably more costly and some items are not even available. If there was a way to get the parts from STUGA-CABAÑA 2022: Der faire Internetshop mit über 20 Jahren Tradition. HYTTA.DE Petroleumlampen - Petroleum - Eisenwaren - Haushaltswaren the extra cost of shipping might be worth it. PreHeater Complete-Part#226-500CP It would be about $9:00 US less getting this from Germany and I wanted to order some other stuff for a Wenzel, plus some stuff just to have on hand.
Really ? I measured mine @ 0.19mm, perhaps my digital calipres aren't as accurate as I thought. I never compared Britelyte and Petromax prices so didn't know that even with postage, it would have been cheaper to get parts from Germany. Have you tried Base-camp in the U.K. ? Petromax Spares Price List
