Found search references to using a bit of Permetex on nipple threads to insure a seal. I'm having a problem with an 8R. Does Permatex seal the nipple so that it (the nipple) is hard to remove later, or does it release pretty easily? Thanks. Hank
Permatex will probably burn off leaving a goo that will make it hard to remove later and just make a mess - if anything try graphite paste etc. regular permatex black or orange RTV can withstand 400 deg F and the hi-temp copper can go to 700deg F the stuff isnt made for direct flame contact environments and will smell just lovely as it gets super hot and burns off Personally, I wouldnt use any permetex sealer on a stove jet nipple, I'd find out why it doesnt seal properly first. How are the mating surfaces? threads? Would it be easier to jsut replace the jet?
Bolexguy..... I need to check the threads and really clean them, which I have not. Stove was sitting in a shed for many years before being given to me. I will replace the nipple. Appreciate your help. Thanks. Hank
sometimes just a good cleanout and tightening goes a long way if its been sitting for a long time dirty there could be carbon and who-knows-what keeping it from seating properly generally a soak in some citric acid or vinegar will loosen it all up and off you go plus it makes it nice and clean I've used graphite cord in small amounts around the threads of worn nipple seats before with good results on stubborn stoves
Hey Hank, I permatex will definitely burn due to the heat output of the burner. I used graphite paste. At that time, the minumum order was 6 cans so I offered CCS members and a number of takers. Firstly the graphite paste once heated expands to seal whatever gaps on the threads then solidifies to a nice seal and still easy to remove albeit it will be gritty. You will just need a small amount so if you need any (I have a 1lb can) send me a PM with your address and will send you some in a film cartridge. You only need to apply it on the male thread sparingly since you mentioned its for mating the nipple to the burner. Of course you still have to tighten the nipple to seat it properly. Ron
Finally caught time to take everything apart. Nipple threads were gunked. Nipple hard to remove.Carefully cleaned threads on body and nipple. Reassembled and still have a leak. I have needle set at four teeth (I think) and there is still fluid running down into the cup. Did not attempt to light. Not yet sure if fluid is coming out of needle because I cannot fully shut off valve, or between threads of nipple, Need to recheck in the a.m. when I have more time. Hank
Hi Parable, the burner does not rely on the cleaning needle to shut off the fuel flow. The needle valve is on the same shaft as the pinion which drives the cleaning needle but when the needle valve is fully closed no fuel should come near the jet, so can't leak through the jet aperture nor the threads. The regulator mechanisn in this burner is very similar: https://classiccampstoves.com/posts/166304 Of course you can always leave out the cleaning needle for a time to test operation of the needle valve and jet. Best Regards, Kerophile
Hi! So you don't light the stove at all but you still have a leak? I bet this leak has nothing to do with the nipple threads, but with the shut-off valve. As you can see in the picture in the link suggested at the post before, the shut-off knob drives a stem with a conical tip that acomodates itself in a hole, sealing it and then shutting off the stove completely. I think you are not getting this sealed anymore. If this is the case, it may have some causes like: - Your cleaning needle was set too low, so when closed, the needle hits the bottom and doesn't allow the shut-off valve to close any longer. To solve this, you have to take the needle off and reassemble at the right point. There's a technique you can find searching here, in the forum, for: cleaning needle, clicks, svea 123 / optimus 8r (they share the same mechanism). This technique allows you to engage the needle at the right point so you can fully close the valve without the needle blocking the moviment. - There's a tiny chip of brass inside the mechanism. A little more complicated, since in this case, you'll have to disassemble some parts to clean it. - The conical tip of the stem is damaged, uneven, not conical anymore or even bended, probably due to overtightness. This may be the worst case, mas easily reversible anyway. In this case, a light repolish with a very fine grit pad (like 1000 grit) could be enough to get the tip even again (it doesn't have to be perfectly conical, but just even). I recall there was a fairly recent topic here talking about rebuilding or fixing a greatly damaged air pressure release valve tip with some detailed photos, but I coudn't find it. Hope this helps. Rafael
Hi, here are some instructions on re-fitting a cleaning needle correctly: https://classiccampstoves.com/threads/8843 Best Regards, Kerophile.
Thanks, each of you, for taking so much time to advise. Am taking a brief break from my "honey-do" list to read replies. Thanks, Ron, for the offer of some graphite paste. I need to take more time studying the problem before I attempt a repair. IF the problem of leakage does end up being caused by the nipple needing a better seal, I will gratefully PM you. I am now thinking that something is interfering with the shut-off, as was suggested. Will start fresh on Monday, when some projects are finished, and when the stove is burning as it should, post my first picture. This makes me appreciate even more how really great all of you are as fettlers. Hank
I disassembled the burner. Near the end of the shut-off valve stem, right where the taper begins, there was a ring of hard crud which was difficult to remove. After it was clean, I soaked the parts and burner, except the packing, for about 20 mins. in white vinegar. Then water washed and heat-dried everything. I polished the end of the stem with FLITZ (didn't have fine sandpaper) and re-assembled the burner, with the needle properly set at four clicks. Pre-heated twice with full dropper of denatured alcohol, so that the burner was really hot, and there was no leak. Fires up with strong blue flames. Immediately shuts off as it should. Sounds like a helicopter. One 8R and one 111T working to perfection. Thanks all for help. Hank
Hi Hank, I am glad it all worked out for you. Now that you are a fettling expert you will need to get some more of these great stoves to work on. Best Regards, Kerophile.
