I have been fettling Optimus 1551 lamps recently. They were my first addiction. Changed the fuel-lid gasket and after some moderate violence needed to check the NRV-valve since it was not pressurizing. After prodding the pip with a paperclip it finally came unstuck and the lamp lit up like a sun. The next step I'm looking at is to get the quick lighter to work. Is there a description of how these work? Nothing seems to be happening even if the pressure is 1 bar on the manometer. Does it need to be 2 bar (the red line)? I don't understand how the lamp can seal so well with the quicklighter not working.
May be the "rapid pre heater" (search forums for that expression) is just blocked? It will normally use kerosene from the tank, mix it with lots of air (also taken from the tank) and spray the mixture towards the generator. You will need to ignite it directly at the lever. The orifice may be blocked, the fuel pickup tube may be blocked, the small holes around the orifice which provide air may be blocked... Erik
The lamp is airtight because the air and fuel holes in the rapid preheater are clogged. You need to disassemble the parts,soakthem in citric acid to clean them,and carefully clear out these small passages-bu tunder no circumstances should you enlarge the hole diameters ,or the fuel-air mixture will be thrown off.Then, reassemble the United using New seals. Check the intake pipe and filter screen to ensure they are clear.Finally , pressurize the tank and check for leaks in a bucket of water;be extremely meticulous during this Stephan and do not tolerante even the slightest leak. The Red Mark on the pressure gaugeindicates the correct pressure for the rapid preheater , Provider the gauge is properly calibrated.
I will now start to dissassemble the quickstart. Do you need to remove everything else as well to remove it or is there a way to wiggle it out?
Ok, I removed the superstructure and then the quicklighter. I now have trouble unscrewing the quicklighter itself. The jet seems difficult to unscrew. Maybe I can still clean it attached. It certainly needs cleaning.
Into the citric bath it went. Looks better, but I wonder if there should only be one hole. I seem to recall other quicklighters with airholes around the fuel nozzle.
This was curious. After applying some 5-56 on the threads I managed to unscrew the top part. Underneath that copper-like part a more jet-like part was revealed. Could it be that this quicklighter was plugged?
No, it was not plugged. After using the blowtorch/quench method I managed to clear what I now read was the outer nozzle. It was completely blocked. I then put it back and tested it on the lamp after about 80 pumpstrokes. At least a lot of high pressure air came out and maybe a bit of fuel. It seemed to light up a bit briefly, but would not continue to burn. I suspect to little fuel, maybe the inner jet needs cleaning too or maybe the airgap between the jet and outer nozzle needs adjusting. I tested blowing air through the inner jet with a bike pump, but it was difficult to know if it came through all holes and not just the air holes on the side. I guess I could test without the outer nozzle and see what comes out. To be continued...
@kephart I suspect too little fuel . . At least half a tank full. Also, check that the filter on the fuel pickup tube is clean. maybe the inner jet needs cleaning too ALL holes need cleaning. maybe the airgap between the jet and outer nozzle needs adjusting. There is no adjustment !
Thanks! I did check the filter. I did some heat quenching also of the inner jet. My pricker is to thick for the orifices of this jet unfortuneately. I did a test with the outer nozzle off and at least fuel is spraying out of the middle hole. Will try now with more fuel inside. There wasn't much left in the tank when I tried.
It ain't over until the quicklighter roars. I can't seem to get the pressure to rise much over 1kg. Now I see it is leaking from the generator jet at the top, not the quicklighter. How can I fix that? Some graphite packing in the valve maybe or a new pricker?
The leaking at the generator is not that bad. Just sort of a drop forming. I have been able to blow air through the fuel tube of the quicklighter with a bicycle pump and air comes out of the jet. It seems to require a lot of pressure, a bit more than 2 bar which I gather is consistent with the required pressure for the quicklighter. The outer nozzle isdifficult to screw all the way down. Is all the way down the correct position? ?
It needs to be just a little bit more than finger tight. Having some thread showing underneath it is correct. If you cannot get the pressure to where it needs to be you have a bigger leak, or maybe a poor condition pump leather. Sometimes the gauge can be faulty. Do you have another one you could swap for testing ? The definitive leak test is to pump it up and hold it underwater. I have also had success using leak detector spray from the plumber's shop.
Thanks! That's a good idea. When looking closer at the outer jet I now see that I have probably broken it. There are cracks on two sides. It was very hard to remove and I think I might have done something stupid. I haven't been able to find a spare outer jet on fogas.se, but they had a complete quicklighter for 20 euro. Not as much fun though. Anyway, I still learn from trying as I am quite new to this domain.
It may be that a Chinese made Petromax one will fit ? - others here may know as I have never tried it.
I would think so. I think the 1551 is chinese made and I think the lighter is the same as for a Petromax 500. However fogas.se says this is the one for the 1551: https://fogas.se/shop/5123---2810-1-snabbt%C3%A4ndare-till-1551/ The one that is on my lamp more resembles this one: Tusentals gasolprodukter på nätet
Yes, sorry. Pasted the wrong url. I guess even if they look the same the length of the fuel tube and other dimensions might vary.
If the Px part is the same size/thread then: Detailseite: Ersatzteil- und Zubehörliste "Petromax 500 HK, Geniol 500 HK und Hipolito 500 HK or Petromax Spares Price List part no 221. But I have never tried this
