Just a quick note with some pics on a fix for a recent acquisition (Optimus No. 1). Love this stove, but found that it started suffering the dreaded NRV leakage in the pump well. I was initially saddened as I didn't think I had the mechanical skill or tools to effect a proper repair. But I was WRONG! Thanks to you wonderful folks here, I was able to craft my own NRV removal tool, fashioned from an old spare screwdriver: It was easy to make using a hacksaw, Dremel, and small flat file. The result was a perfect fit on the NRV's small brass head at the bottom of the pump well. A simple counter-clockwise twist and the NRV came free, unscrewing easily! The leakage problem? Apparently, the NRV spring was broken in two places, resulting in an improper seal with backflow through the NRV: Thanks to you folks here, I knew *exactly* what to face, how to extract the NRV, what the NRV was going to look like, how to disassemble it, and how to do a repair. The pip seemed fine, so I reached into a treasured Mom-and-Pop hardware store find (Tom's Hardware, downtown Hamilton, OH) - my 'Bag O' Springs': I dug in and found a similar diameter spring with a slightly stiffer, but equivalent 'spring' to the original, and then clipped to length, reattached the pip, screwed the NRV back together, added a small Viton washer (in lieu of a lead washer), then re-installed the NRV. It took less than 60 minutes from starting to make the NRV tool to completing a newly refurbished stove! So my advice to anyone out there facing a similar, seemingly daunting task: Give it a try, but do your research here on SB first! Thanks, folks! [off happily enjoying a cup of java on the lanai, made on a (somewhat)-new Optimus No. 1]
Good job. And, the bag-o-springs pic, with an appropriately obtuse title, could be hung in a New York photo gallery.
you're too kind - but believe it or not, that bag, purchased six years ago, has come in handy a number of times... the cool thing is that the place is *still* in business - and i'll be visiting there during the next week! now i wonder if i'll be able to find some nice pump washers or pressure-stove parts...
You did a great job on the wrench considering the tools you worked with. I have to tackle the NRV on my Hipolito, what is the width of the slot/gap on the wrench? Thanks
little over 5mm - once i got close i was careful to file square, test fit, file some more, and so on until a good fit... tks for the kind comments, all - i'm just relieved to know that i can fully maintain the stove, including making my own pump leather, as i have quite a bit of material on hand (12 years ago i found a Tandy Leather shop in Fredericksburg, Va. that was going out of business and spent beaucoup dinero on hide, punches, etc.)
Well done Linux!! Keep that great NRV tool you made as it will probably come in very handy when you buy some more stoves that need a little fettle . I made one very similiar to yours out of a 1/2" impact extension and have used it numerous times with great success. Have a great evening, Dan
Hi Guys I am a newby here and was wondering if this site contains a step by step for renovating a primus #1 .. how to remove the NRV, how the NRV works and how to make the tool that removes the NTV? Cheers
Welcom Grbeiz, there are lots of topics on NRV's and the Optimus 1, just do a search on both and you will come up with a lot including tutorials. Ron
