hello everyone. There are two problems with the 252. the first After ignition, the fuel valve can not be opened because the fuel flooded the lamp, the light is reduced and the fuel burning outside the stockings. second If after firing, it does not open the fuel valve completely, the lamp burns readily, but after a while (a few minutes), the pressure drops, the light starts to blow. If I add more pressure, and still works well for a few minutes, then start it again. I do not understand why it would work differently if a tank pumped, and then let him out a little hole in the pressure, the pressure is reduced, of course, what would set pressure? Does anyone have any idea what could be the problem? Thanks for your help.
Hi Roy, I see you are in Budapest. What fuel are you burning in the lantern? While designed to burn gasoline the Mil-spec is a stubborn and finicky lantern. Yours makes a very nice light. For your first question. To start it only use around 10 pumps, these lanterns love low pressure to start and the flood quicker than you can say stop. Too many pumps and the lack of a burner screen usually results in a blown out mantle. Crack the valve open until you hear the fuel reach the generator nozzle then close the valve and preheat the generator with a couple of matches of a small torch. Be careful using too much heat as the generator is aluminum. The mantle will ignite and burn then open the valve. Once the burner heats up and you have a good burn you can add some more pressure. It's been a while but somewhere between 40 and 50 pumps should keep you in good graces with the lantern. For your second question. It sounds like you have an air leak, the very first thing to check is the fuel cap gasket. Pump up the lantern and spray a little soapy water on it. Odds are you will see bubbles. If the cap gasket is bad I will gladly send you some with instructions on how to install it. Please let us know how you come out on this.
40 to 50 pump strokes is too much. These are a low pressure lantern. 10 to start it and then when it is running a further 15 to 20 is max. Do NOT take a blow torch of any type to this generator. The generators are alluminium and will melt if you use a blow torch. I know this because I have done it and the result was interesting and exciting. Matches only or a blow torch flame to the mantle only. The lighting procedure is 10 pump strokes then open valve a half turn and light mantle. The lamp will splutter and flare and then settle. Once settled to a steady burn open the valve fully. The mantle will again splutter and flare. Once it settles again then pump a further 15 strokes which will probably make the lamp flare up slightly again but it will then setle and run. Because these are a low pressure lamp any leaks will mean it will fail quickly. An under water pressure test is therefore essentiall before trying to run one for the first time. ::Neil::
Thanks for the replies. The ignition is perfect for you as you suggested, but the sequel does not work. When the valve is fully open, it begins to be in flames, but there is no change, the flames remain. If you increase the pressure will increase the flame size, but the other does not change ...
Hi Roy, If you are using the correct fuel (what fuel are you using?) and there are no leaks (you have done what John and Neil suggested) then I think you may have a generator problem. First, have you cleared the generator jet with the pricker tool that comes with the 252? If so, and it still does not work well, here is my thinking. If you have a clogged generator, it can vaporize a low volume of fuel as when the valve is partially open. When you pump up more pressure and open the valve more, the clogged generator can't vaporize the additional fuel flow and you get a fire ball. Just a thought. Do you have new generator to try? Dan
Hello Dan D! The fuel variable, because in hungary no coleman fuel, so i try first is a normal car gasoline, but don't workin well, secondly i try light gasoline but not clean 100% just 81% 80/110 specbenzin and 19% isopropyl alcohol. I could only do that buy. I'll try the clean 80/110 specbenzin, because i think that is similary to the coleman fuel. What do you think? I used clean the jet, with blowtorch, in screwed out state. Heating to around 500-700C and drop in the water. I saw this technique in the very old catalogue.So it's clean. The generator is new i bought it from oldcolemanparts website. So i wrote this forum, because i haven't more idea, what is problem. p.s. if my english is not understandable, i'm say sorry, because i using google translator and i'm know a little english.
These generators are designed to run at the lowest temperature possible to vaporise the fuel. The idea was to keep it as cool as possible in use. That means the lamp is always running very close to failure. One thing that will affect the burn is the mantle shape. It has to be close enough to the generator to heat it. The wrong shape with too much gap and the generator will not work right. So try a rounder mantle that is closer to the generator tube. ::Neil::
Thanks Neil! I'll try it, and i thought of that. So i added a little heat to the generator tube, when is working, ( a match flame ) the heat help vaporising the fuel and the flame to be burning well.
I tryed the bigger mantle, and added some heat (with denaturated spirit) so the lantern is working from half hour. So you right Neil, i think this fuel what i use, have a higher boiling point.
Good to hear you got there. You need to be carefull applying heat to that generator. Aluminium melts at 660c and you can exceed that with some preheating methods. Alcohol is probably OK though. These are always tricky lamps to run and you have to use the right mantles and lighting method or they won't work. I sometimes wonder why the US used these for 40 years when they are such beasts to use. I guess it was the ability to use leaded gasoline that kept it in service rather than any other considerations. ::Neil::
I used alcohol at once, and now working the lantern normally, don't need nothing else just a matches. I have been thinking a lot, why this lamp was used for military purposes. It is difficult to operate.
The military liked it because it was the only lamp that could use leaded gasoline and they did not therefore need to carry a special lamp fuel. In the field it could be filled by syphoning off a little gas from a jeep or a tank. ::Neil::
