Having done 2 before, following guidance from the forum, I started the next. All washers changed Pressure and air test under water no leaks. No the issues First time fill tank about half to three quarter, pressure about 12 cycles, heat the burner with meths, meths bubbling at end, turn fuel on flames every where. Shut down, empty and recheck in water still no leaks, used meths to clean pre heat dish and tried again, same result. Today, was going to try again but pressed the tank before applying meths to pre heat dish. Fuel coming out onto pre heat dish. Any clues please?
That can only be out of the jet nipple, not vapourised. In spite of the 3-sided windshielding, the fourth, front, side is open. The slightest of breezes can divert the priming flame from the vertical and the paraffin fuel won’t get hot enough to vapourise. A sheet of metal serving as a temporary windshield just for priming is the answer. Also, twelve pump strokes (‘cycles’ you said) is about half of what’s needed and if the NRV is defective (spring too strong) even two dozen pump strokes won’t pressurise the fuel enough.
Many thanks as always for your advice. I stopped and posted here more for why fuel ending up in the pre heat cup. I can't find a leak with air test. I want this one sorted before I go into the next No2. Frustrating doesn't come into it as you think you have checked everything.
@Surveyor,, hi I had similar problem,, Presscall helped me big time,, with tips and advise,, very helpful guy,, there was lots I was doing wrong,,,, overfilling tank,, not heating burner enough etc,, For getting your burner hot try using a baked bean can for wind shield,,, Branston brand is perfect diameter,, cut slots with scissors one for control valve another for feed pipe,, lift to fill cup with meths light then push can over burner,, wait until flames are almost gone,, before slowly opening valve,,, I find 30 pumps sufficient prior to the above,, it works for me,, you can remove the bean can with pliers after lightning or just leave it on,, give it a whirl,, Good luck Neil
Neil Yes agree with your comments regarding Prescall, there are others as well, sometimes it's who answered first lol
Got back to this pumped nearly 30 times and fuel leaks very slowly onto the pre heat cup, before I start stipping is it possible I need a replacement part, like the needle that control the flow?
Hiya,,, turned out my burner had tiny leak inside the ring of the burner,,,yellow flame to part of the flame,,, would leak parafin into preheat cup,, gradually got worse until i would find parafin on my floor,,, i did submerge test in water,,, tiny stream of bubbles came from the join inside the burner circle,,, i managed to find complete new burner on ebay £50,,,,, its an awesome stove now,,, i got the square army pans for the number two,,,, im the only guy on the campsite that cooks fish n chips,,,, sounds like an f16 though,,, when it fires up i always get friends coming round to scrounge a plate of chips,,,lol,, i had issues when i first had mine,,, prescal helped me big time with advice,,, stick with it,,, its an awesome stove runs forever on one tank of parafin far mor efficient than the coleman petrol stoves. good luck Neil
Many thanks, I did a water test as well, no issues, but good point will try again, with the air test. I suspect it could be the needle and considering buying one in case. Got 2 more number 12 to sort.
Hi @Neil Headwhipper . Interested to hear of your leaking burner. Some time ago I had a burner leak problem with an Optimus 111 fiitted with a silent burner: Optimus 111T burner fault - A mystery solved! Best Regards, Kerophile
Hi, here is something else to check if you have a fuel leak from the burner of a No.12 Military stove: 1996 British Army No.12 @Trojandog Scan down until you see the photo of the leak location. These leaks can be challenging to locate as they only open up when the burner gets hot, the metal expands, and the crack opens up. Best Regards, Kerophile.
Thanks, the leak and when its flames appears around the pre heat cup. I hope to get back to the issue today, paid work permitting as away this weekend, looking for parts for my restoration projects.
