Good evening, I posted on this lamp a long time ago. It's been standing for a while now and since I have time on hand I might as well get on with it! I've cleaned it up, oiled the pump leather (which looks dry but o.k.) and tried to build up pressure. Seems the NRV is not working anymore, so no pressure and no starting yesterday. Also since this is a petrol fueled lamp I don't really trust it unless the seals have been taken care of. And since the petrol that came out was liquor coloured (so a bottle as container seems appropriate) and the mantles that came with it where payed for in Guilders (F.) that must be a long time ago! So, the big question: Which parts and seals will need replacement, and where does a Dutchman acquire these? Kind regards, Bram van Houten
@Bram van Houten Hello, parts should be available from eBay for sure and other suppliers as well. You probably won't be able to determine what parts you will need until you do some testing first. I would start with the "dunk" test first; drain the tank, pump air into the tank and place in a bucket of water, and then look for bubbles. That should tell you to some extent what seals may need replacement. Give this a try and then let us know where, if any, bubbles are appearing.
Thanks @george Unfurtionatly there is zero buildup of pressure. I think the NRV is faulty or the system is so leaky that pressure buildup is not possible.. Should iIorder a NRV first and then start the testing?
Make sure your pump leather is soft. If it's hard then you can't build up pressure, put some oil on it and let it sink in.
@Bram van Houten Only one seal required on a Mil-Spec, the fuel cap seal. These can be obtained from fettle box, or ebay. The mil-spec is a simple lantern: a. Check the NRV is working by pumping pressure in. The NRV is a ball bearing within a shaft - if it is free you should hear a faint rattle when you shake the fount. If you cannot get pressure into the fount, spray the pump tube with carburetor cleaner to see if you can clear it, or use a thin wire to prod the ball bearing. In extreme cases I have soaked the inside of fount in citric acid to remove the crud and free the NRV. b. If the lantern still does not work I'd strip the whole thing down and check the fuel pick up (if you are able to remove from the fount). These can clog up with fuel residue, thus don't pick up fuel. I use citric acid to clean the fuel pick up, in conjunction with a brass wire brush and OOOO grade wire wool. On re-assembly I use copper slip grease on the joints to ensure a good seal. Once re-assembled remember for your test fire you only need 4 - 8 pumps of air to pressurize, they are a low pressure lamp.
@Bram van Houten What @Alex Smith has said, he’s spot on with his advice. The NRV valve is the earlier ball bearing type with a positive shut-off air stem. If the NRV is only slightly leaking the positive shut off should, when used, stop any pumped pressure from leaking back out through the NRV. After clearing the NRV ball, I would suspect the fuel cap seal and or the pump leather. As you work through the fettle, you may find that the generator is blocked. The 252A is made from aluminium tube and I would think it would be difficult to do the usual heat quench carbon removal technique. You may get it going using carburettor cleaner. Failing that, these generators, and all the seals you need are available from: OldColemanParts.com The 252A, when running will roar. I like this roar and quite often have a coffee while I listen to the “jet take off”. Good luck on your fettle. Cheers Pete
@Alex Smith Having never used citric acid to clean anything before, what proportions do you make your mixture to please? Regards Jeremy
@X246A Jemery, let me know how it works for you. I've thought about citric acid but just a little afraid to try it.
@george I have always used citric acid, the same that is used for cooking. I make a solution using hot water and only immerse brass parts for a maximum of 30 minutes. Dependant on the concentration, this is approximately the time that it takes to get a slight pinkish hue on the brass. Because citric acid will erode nickel, I’m a bit hesitant in immersing nickel plated parts into the citric acid, if I do it’s only for a maximum 10 minutes. Cheers Pete
@AussiePete Pete, How did the nickel turn out when you immersed it in the critic solution for about 10 minutes?
@george I’ll keep you informed, however it will probably be a week before it arrives. Once I have it in hand I still have to pluck up the courage to do it. Guess it’s just me but I always feel the same when trying something for the first time. @AussiePete What is your preferred concentration please? Regards Jeremy
@george It turned out very well. The diluted citric acid removed all the crud and, after a thorough rinse in clean water, made it so much easier to final clean. @X246A I use approximately 1 table spoon to 2 litres of hot water, not boiling, but about 60C. The hot water speeds up the reaction relative to cold water. Cheers Pete
@AussiePete Hi Pete Your mix is dramatically weaker than the mix used by @Sellig33. I think I’ll start on the weaker side and experiment upwards. Thanks to all. Regards Jeremy
@X246A I tend to use "1 ish" (or 2 ish) table spoons to 500ml of hot water - we all have different "mixes". Some of my mixes are less scientific i.e. measured by eye, so may be stronger or weaker. Rather than focus on the mix itself I tend to keep an eye on what I have in the mixture - if it is brass and starts turning pink I remove it and wash off with soapy water. If the crud is difficult to remove from the item I'll bath it for a while, remove it, wash it then use a brass brush/OOOO wire wool to help the removal of crud. The key for me is keeping an eye on what is happening, rather than a specific mix. One point to note - critic acid destroys graphite seals/washers. I tend to keep graphite out of the mix, usually by suspending the item by wire to keep it out and dry. Hope this helps - this method works for me.
George I see no reason why you could not. You would need to keep an eye on non-ferrous materials like brass to make sure you weren’t, for example, leaching the zinc out. Tony
@Tony Press Tony, thanks! I often thought about trying that but I figured with my luck I would ruin the ultrasonic cleaner!
@george I never thought about using diluted citric acid in the ultrasonic cleaner. I can’t see any obvious reason why it shouldn’t work. As Tony said, one would need to keep a close watch on it, but with use, one would become familiar with the “how to”. Cheers Pete
@AussiePete I'm "gun shy", I already wrecked one ultrasonic cleaner by not draining the damn thing! My son managed to clean it up, so I gave it to him. I bought a small one and with what brain stem I now have left I manage to remember to drain and clean it when I'm finished. When I feel better I'm going to try the citric bath and see what happens.
@george Hope feel better quickly. Yes, it’ll be very interesting, keep us in the loop. Stay safe Pete
If your ultrasonic cleaner is big enough, you can fill with water, then put your small parts in a jar and fill the jar with citric acid. That way you only need a small mix, and it's easier to fish all the bits and pieces out. I had a lot of success with a few different chemicals in jars, degreasers, acids, etc. Just cycle the different parts through the various jars.
Has anyone tried vinegar/salt mixture? I have an old book that has a copper/brass cleaning formula. I have tried it on a brass fire extinguisher. The results are very quick.
@MarkC I don’t own an ultra sonic cleaner yet. Obviously something I need to invest in. @Rob Mikell I read you had used this method in another post on this forum. Would it be possible to scan or reproduce the instructions from you book please? Regards Jeremy
I've come to this thread late but a couple of points:- 1. Some of the seals etc. that are needed may be in the spares-caddy thingie in the tank; 2. Vinegar (the cheaper the better, I've found) is probably a good substitute for citric acid which is sometimes difficult to obtain in the UK; 3. I agree with Pete that heat and quench won't work on the vapouriser - being alumin(i)um, it'll melt before any carbon build-up is burned off. I got a replacement vapouriser from Leacock Coleman but I think I've seen them on eBay occasionally. 4. They're a low-pressure lantern so don't pump it any more than necessary - generally, once it stops getting brighter, stop pumping! Best of luck with your fettle...
We live in a hard water area and I used to de-scale a lot with vinegar, but it always took so long to rinse away the taste/smell. Started to use Citric acid instead and just transferred it to my other projects. Both do a good job, and can recommend to use whatever is the most convenient.
Both vinegar and citric acid work fine and not so corrosive aa to pose any serious risk in most cases. The latter might not be readily available in many areas. I've tested it(citric acid) at the highest possible concentration(saturated) without much problems other than unnecessary wastage. Not recommended on nickel or zinc-plated parts. Somewhat ok on chrome-plated ones. Not a good idea to immerse both steel and brass parts together in the same bath. You'll end up coating the steel part with some copperish layer, which can be troublesome to remove.
