Arne, Glad to know you were able see my thanks. Useful is an understatement. Without your pics of the disassembled cap and the drawing I would have been lost. I would not have known how the NRV shaft/tube was attached and if it was safe to try unscrewing it, not wanting to try at the risk of breaking it off. I wouldn’t have found the seal/pip was disintegrating and that the hole running through the release value "cup" was completely blocked with remnants of the pip and it was safe to use a paperclip to clear it. Again, I can’t say thanks enough. So now that I’m looking back at Arne’s old post I’m a bit confused when reading Doc’s 03-02-15 05:19 PM - Post#319967 above. I see Arne’s caption for the second picture says “The NRV parts left and the parts for the pressure release to the right.” I took that to mean the tube/shaft, spring, and seal/pip are the NRV. Doc says the pip is for the SRV (safety release valve) (which I assumed are the parts to the right in Arne’s picture). Can someone clear me up on this? Tanx, KMK
Morning, KMK, I've always called the valve in the bottom of an actual pump tube, the "NRV"; for the same thing, used in a fuel cap, I call it the "SRV. The NRV keeps fuel from seeping into the pump tube, and allows you to use a built-in pump, like the 111 family of stoves has, to great effect, allowing air into the tank as you pump, and blocking fuel from coming out of the tank when you stop pumping. The SRV serves a similar, but to me, distinctively different function. As you use your stove, the fuel tank builds up pressure inside it, either from heat, or from pumping. IF the pressure gets too much for the rated safety margin of the stove, then the "SRV" in the fuel cap opens up, and releases that over-pressure. Sometimes, you just see a candle-like flame at the top of the fuel cap, and other times, a flaming stream of gasoline can be spewed out that same area!! So, an NRV keeps the pressure of pumping inside the tank, and the SRV (in the fuel cap) releases pressure when it gets to be too much. Your 199 does not have an NRV, per se, as there is no built-in pump. So, with your mini pump, the fuel cap SRV performs both functions: allowing pressure to be added when you pump, and also releasing that pressure, if it gets too much. I hope that helps you. But, if I've only further muddied the waters, please give a shout, and I'll try again. Your SRV pip should be arriving any time, now, if it hasn't made it already. Good luck, and God Bless! Every Good Wish, Doc
Doc, Thanks for the explanation. Based on Arne's old post I was able to understand how the whole fuel cap works. I was just trying to reconcile the differences in terminology the two of you were using. Hey, as long we understand how it works that's what really matters. About the mini pump, does it have two O-rings; one on the open end that fits over the fuel cap and another inside around the shaft? I haven't yet figured out how to safely remove the end as you describe. I can get a good grip on the flat side with a wrench, but I'm afraid I'll damaging the other nice round smooth "half" of it if I grab it with anything other than my hand; and that's not working. Tanx, KMK
Howdy, KMK, I dug up an old Optimus Mini-pump that came with a SVEA123 that I bought many years ago, but have never used. The pump is dirty, and needs a good cleaning, and lubing. So, I took it apart, using a large crescent wrench, and some rubber mat that really grips things tight, and keeps them from slipping. No vise was needed. Here's how it turned out: You can see the dirt and grit on the pump shaft, and all that needs to be removed. You can also see that there are two o-rings, and the only one that is easy to service, is the one on the pump shaft, which can easily be removed and replaced. The other o-ring is pretty much captive, inside the end piece that I unscrewed. I've never had to replace one of those, but I think it would be done, with a very steady hand, and an awl that would allow you to pry it out, if necessary. Putting it back in, however, is going to be a challenge, me thinks!! I hope the photos show you how it all looks, and that, using some non-slip matting, as shown in the photos, you can easily remove the threaded end cap on your Mini-pump. Now that I have this one apart, I'll do a nice clean-up, and then lube with powdered graphite. Once the pump is reassembled, it will work like a champ for many years, with no further service necessary, unless you tear the pump shaft o-ring, which, if you lube it properly, should not happen. We're down to being able to use only one computer at a time, as our router looks to have died on us. So, after I send this, I'll have to let SB have the model connection for a few hours, at least. I'll check back later this afternoon, or this evening, and see if you have further questions. Hope this helps, and God Bless! Every Good Wish, Doc
KMK, If you don't have the mat Doc shows, maybe a piece of silicone bakeware. If you can find a 'strap wrench' at a hardware store, that will grip round surfaces. Ken in NC
Doc, Thanks for the pics. Yours still has a readable label. I'm sure me or my son have something around the house that will work like the mat. Now that I see how it comes apart I feel safe trying. The pip didn't come in yet, maybe tomorrow. If it does, it'll be a top priority to put it in the cap and work on firing up the stove. I'll take some pictures then and come back and post them. I'm just hoping that the o-ring in the SRV is still good. From what I can see it still is. I just haven't been able to unscrew the top part of the fuel cap to inspect it to be sure. Unlike the six point top in the pictures in Arne's old post that probably just takes a common size allen wrench, mine is five-sided and I haven't been able to find the tool for it. With the pip in the condition it was in, I wonder how far behind the o-ring is. Tanx, KMK
Hi, KMK, Yep, you need a special tool to service the o-ring in the SRV setup. It's called a "Penta-wrench", or something similar. A former member here used to make and sell them, and you can check Bluewater Stove Restoration, to see if those are still being offered. I've seen them on eBay, too, but very, very seldom. I seem to recall that our own Presscall, a fine fettler if there ever was one, filed a regular hex wrench to size and make it fit. Don't quote me on that, but that's what I seem to remember. Anyway, yes, there is a little bit still to learn, and a few more tools to gather. Talk soon, and God Bless! Every Good Wish, Doc (now the computer setup goes back to Sweet Bride!)
The 5 sided tool is very easy to make with some round rod and a file. I made mine from an old screwdriver.
YOOOOO HOOOO. YES, YES, YES. I was like I kid on Christmas morning. You might gather I got the pip that Doc sent me and I got my stove working. And you would right. The temperature was in the low fifties yesterday afternoon, and it didn’t want to light with just a preheat. So, hoping that it was just a little too cool, or maybe just I little bit clogged somewhere, and not something else that was too worn out on it, I closed the regulator and let it set a few minutes, gave it a couple pumps, repeated the reheat, and then… it lighted. I was exuberant. It did a lot of sputtering and coughing for a couple of minute, it hadn’t been lit in the last 3-5 years after all. But then it smoothed out and got into that beautiful, low, mini jet engine, sounding roar... So I had to get the pot out of my 40+ year old Boy Scout mess kit and boil some water. I put in about 12 oz. of water; it took about 1 ½ minutes to get to full boil... I shut it down and let it cool of for over an hour. I was able to light it again without pumping, just the preheat. Could be that after sitting unused for so long, it just needed a good burn to clear out the plumbing (i.e, the sputtering and coughing for the first couple of minute). One more shot out of the sunlight to better see the flame... THANK YOU one more time Doc. You helped make my weekend like Christmas in February. KMK
Hey, KMK, Outstanding news, Sir!! I'm so glad that everything worked out well for you, and that your great little 199 is singing the "blue flame song" once again!! Well done, and I'm glad the pip worked out for you! Thanks for sharing the good news, and have fun with your 199! God Bless! Every Good Wish, Doc
