Dears, Petromax 2821 develops "fire ball problem", but quite unusual: - sometimes it runs OK, sometimes it "coughs/spits" and suddenly there is a "fire ball" around the mantle. Currently I installed new 150CP jet. I verified that there are no leakages. Inner casing, J-tube and the whole lamp seems to be in good condition. It received a good cleaning, so it should be fine and even was fine some time ago. The lamp was posted before here: Petromax 2821 I do not know what is going on, so maybe there is some blockage/fuel flow issue. The generator was cleaned, but not the Preston loop. I do not know how to make sure that there is no issues with that loop and clean it from inside (I do not own ultrasonic cleaner). I have read somewhere that lamps should be fine even with clogged loop, but do not have better idea what might be a cause of the problem. As always I would be grateful for all/any ideas/advices. all the best, Piotrek
They can be a swine to clean My preferred method is heating/quenching to shock crud loose, gently dry it and then blast what you can out with compressed air. Repeat until clear. A tip is to drop a ball bearing down the tube so that when you blow it/flush it, the water/air all goes around the loop instead of partly through the hole in the centre (for the cleaner wire). A section of bowden/brake/wire control cable (as mentioned above) on a drill used like a rotary wire brush inside the loop also helps but its often one-shot deal. After the cable comes out its impossibly spikey (and now invariably bigger than the hole) and you have to cut it off to try and get it down the hole into the loop again But it does work... Happy fettling! Alec.
Thank you @Rangie and @Fireexit1 . I have also some metal guitar strings, so maybe it will be easier to use them then a bicycle brake cable. I will try both. Shame on me that I neglected these loops so far , but obviously that part of restoration process is not popular on YouTube / in general and I was always keen to jump to another lamp waiting in the fettling queue.
To be honest a lantern normally needs to have done many hours of service before a loop blocks up - but we never know the history/use/misuse of most things we get. I have had the "flaring" you describe being caused by small pieces of carbon I assume going up to the jet and then falling back down. Cleanliness as ever is next to godliness. Good luck !
Piotrek, when using the cable be careful not to damage the threads in the top of the generator. I slide a piece of steel tube between the cable and the threads.
@ROBBO55 Thanks a lot Martin. Just in time, because I am quite efficient with damaging stuff while repairing them
Dears, Some update: 1. I cleaned Preston loops in two problematic Petromax 821 type lamps with steel cable. 2. To protect threading I used Petromax jet and drilled a hole in it. It can be screwed to the generator and cable goes through it - pics attached. 3. The lamp that "coughs/spits" had quite a lot of dirt inside. Dirt was removed during some tapping on the loop after wire cleaning - pics attached. Now that lamp runs great, no problem at all. 4. No dirt was extracted from the lamp with "fire ball" problem. Maybe it is clean, maybe I should try heating/quenching method. There is still a "fire ball" and "black mantle". It takes longer for these problems to occur then before cleaning. Also there is some small amount of white smoke visible after a while from the jet/J-tube inlet area. I sealed jets with thread lock or muffler paste, so that should be not a leaking jet. Lamp runs better without the top hood. With the top hood attached the mantle turns black very soon - seems like over heating of the J-tube. I changed the jet for another new one and no difference. Different air gap - no big difference. I expect that the problem has nothing to do with the generator but with the J-tube. I will swap whole inner hoods between lamps etc. test more and we will see. I will also try heating/quenching method on that Preston loop. Anyway, thanks for your help and attention. It is good to know that at least some of problems can be solved. I will add Preston loops cleaning as an obligatory point in my lamps maintenance. all the best, Piotrek
The inside of the loop is a passage for kerosene. I thought it was just a part that receives heat. I hope replacing the J tube will solve the problem.
@Camp numao The bore diameter at the main, vertical part of the generator between loop ends is narrower and almost filled by the conducting rod, so fuel is forced to go through the loop. Smart design. Loop that only receives/transfers heat is in Hasag 102 Petroleum - Hasag N0. 102
Hi Guys, Some update regarding my fettling adventures. Might be helpful for others. After swapping inner casings between lamps I verified that problem had nothing to do with mixing tube as I presumed before. The issue was the leaking jet threading/connection with the generator. I tried to seal it again with: - thread lock - the connection was not tight after lamp was working for several hours. So the thread lock is not a reliable solution for so hot joints. - muffler paste -did not work either in that case - muffler paste mixed with copper grease (just to try it...) - did not worked either Then I remembered @MYN statement "Also, since the threads are straight, sealing is actually effected by sufficient pressure on the mating surfaces of the jet's seating on the vaporizer when fully-tightened. The threads alone are not expected to seal like those on tapered ones like BSP/NPT/NPTF threads." So I had a look at the rough surface of my generator top and polished it on 1000 sandpaper, so it had nice smooth surface: After that I installed NOS Radius 200cp jet and needle and screwed it really tight. Then the connection was air tight. Additionally I had to dismantle and clean the whole lamp again, because it sometimes turned into flame torch and required several turns of cleaning needle. I emptied its tank many times (when looking for leakages etc.) and noted carbon dirt/debris/dust at the bottom of the fuel bottle. I cleaned the lamp before, but obviously leaking jet caused other problems (my theory) that caused carbon accumulating in generator, falling down to the tank and contaminating fuel in the tank. Part of that stuff from the tank is visible on the pic below: If someone has other explanation for that, then I would be grateful to learn even more from that lamp. Now both lamps work fine and I can finally move to other projects All the best, Piotrek
Glad that you had it sorted out @Piotrek Loosened deposits from the Preston loop generator would always tend to foul up the remaining fuel in the fount. There is nothing along the fuel line to prevent that. It can happen both during operation or at shutdown when the unvapourized fuel would receed back into the fount. It still happens but to a lesser extent for units having a foot valve or a shut off valve.
Yes I am really glad that I am done with it. Thank you guys for all help and advices. I like to learn from other’s projects, so I confess some additional adventures with that Petromax 2821. Some may find it educational, some maybe funny. - I cleaned the tank from inside shaking it filled with small nuts etc. - When I was doing air tightness test after that, submerging the whole lamp under the water I noted a new, tiny hole in the tank side… The tank had a dent before. That dent, was filled in, polished, painted etc. by me months ago. Obviously, tank wall at the edge of the dent was very thin after polishing. The hole was created during nuts shaking process and/or just after when the tank was pressurized for an integrity test. One can imagine how happy I was about that new discovery… - I repaired the tank with approx. 50ml epoxy resin. I did not used Caswell epoxy dedicated for tanks this time (to expensive incl. shipping, border fees/duties etc.). I just took some “universal use” epoxy reign dedicated for steel, wood, concrete etc. - After two days of epoxy drying I tried to pressurized the tank again and discovered that pump did not work – NRV (left inside during epoxy sealing) was sealed with epoxy. Again, super happy about that new discovery… - I managed to remove NRV, cleaned it and put it back. Fortunately I did not have to remove the whole pump tube to do that… - Another underwater integrity test – everything was ok - Lamp assembled and running fine for approx. 3-4 hours. 2821 has a steel tank, so it is maybe even better, that now it is rust protected by epoxy from inside and enforced in dented area. But I would prefer to do it if/when I wanted it, not because I had to as a follow up of my mistake. I poured some kerosene into the jar with epoxy resin remains – I will check after several weeks and months if kerosene impacts epoxy or if that still holds good to the jar. If everything is fine, then I may use that type of epoxy in the future. Caswell lantern sealing kit incl. shipping would cost me more than my average lamp. Lessons learned for me: 1. Preston loop to be cleaned always 2. Jet tightness test to be done according to @Reinhard instructions before and after lamp works for several hours, because heat may make a difference in jet/generator joints sealing. 3. To be more careful with repairing tank dents, polishing etc. dented areas 4. To be more careful with epoxy resin 5. Check other possibilities and correct mistakes, before blaming Petromax J-tube for problems all the best, Piotrek
A general purpose epoxy resin should still hold up for quite a while with regular kerosene. It'd hold up even longer with odourless kero or mineral spirits which are mostly aliphatic/paraffinic hydrocarbons. It might not last that long if the fuel is unleaded petrol, which contains substantial low boiling point aromatic hydrocarbons. These have relatively higher solvent powers. It wouldn't last very long if you fill the fount with acetone or MEK. For epoxies, the Novolac or phenolic varieties usually have the greatest fuel and solvent resistance. These varieties aren't that commonly available. They are officially approved for use as tank lining on commercial / marine fuel tankers and fuel storage tanks.
Thank you @MYN I will google these epoxy resins. To be honest it is hard to get detailed specification of kerosene available from different shops in Poland. Different names, very often no detailed specification provided. The one I currently use is from the main Polish refinery and described as follows: "Kerosene for lighting is a deeply purified mixture of simple and branched saturated hydrocarbons. A multi-stage, catalytic treatment and the way this process is carried out allowed to obtain a product with a mild odour. Our kerosene is almost completely free of aromatic compounds and sulfur that can cause corrosion." and from MSDS: "A complex combination of hydrocarbons obtained from the starting petroleum by treating with hydrogen to the transformation of organic sulfur compounds into hydrogen sulfide, which is then removed. It consists of hydrocarbons having carbon numbers predominantly in the range of C9-C16. It boils in the temperature range from about 150°C to 290°C. " Orginal "PETROMAX" kerosene is much more expensive. Could you please comment on this product as a fuel for pressure lamps? It works, that is what I know. Piotrek
If any of the kerosene that is sold or available is provided with the MSDS, I'd say it is already sufficiently detailed and reasonably trustable. In my location, a lot of products have unknown sources and without MSDS. No addresses, contact numbers, or whatsoever to enable traceability. That is:- "Use at one's own risk." The stated description of the fuel you are currently using is in general, what would be usual for kerosene and similar fuels. In the MSDS, the composition would usually be provided together with the content percentage range. The CAS No. of the content(s) would also reveal what is the specific substance, chemical or material in the product.
I wondered if that deposits from generator may be caused by wrong fuel. I was trying to find in Poland that "famous" 1-K Kerosene or Kleen Heet or jet fuel that are often mentioned here on the forum, but gave up. Yesterday the lamp was working again for several hours - no issues and no new deposits in the tank discovered. So that was not the fuel problem. It is all right now, so it will go on the shelf to gather dust. Anyway I agree with the following:
Have you tried online from this site?: Buy Crown K1 Clear Pure Petroleum Based Kerosene Case of Four 1 Gallon Jugs Online at desertcart Poland
Approx 400$... Not even sure if duty taxes are included or not. Usually there would be additional VAT and approx. 30% custom fees for new products from USA. The same applies for shopping in UK (thanks BREXIT). Maybe as a X-Mass gift for my wife? But wait... just this morning I bought some small, petrol Maxim lamp "for her" , so she does not need Kero Being serious about fuel, I will stick with Polish Kero that can be bought with MSDS, so quality is assured. Maybe one day I will try Petromax fuel to check the difference. Regarding epoxy resin - I will not use universal/multi purpose epoxy in any future projects if there is a chance that this is not just a marketing bullsh.. and dedicated epoxy can make a difference. I still have some from Caswell kit and that should last for several small projects if needed.
I think 1649zł for 4 US gallons of 1-k kerosene would be way too expensive for me too, even with VAT, custom clearance and other charges inclusive. Anyhow, if you are specifically looking for true 1-k kerosene, then do check that the composition has the CAS No. 8006-20-6 stated clearly in the MSDS. Preferably at or close to 100% by weight or volume of the total content. Klean Heat isn't 1-k kerosene but a variety of odourless mineral spirit. It has a different CAS no. 64742-47-8. It is near-odourless, more refined and produced and treated differently. It'd be informative to check the Physical properties stated in the product's MSDS too. The boiling ranges, flash points, etc should be revealed as well. Even with the same cas no., the stated boiling ranges and flashpoints can be significantly different for different product names or brands.
