Optimus NRV Wrench

Discussion in 'Fettling Forum' started by LanceO, Apr 17, 2021.

  1. snwcmpr

    snwcmpr SotM Winner Subscriber

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    The reassembly is not a problem until it has been there another 50 years... :)
     
  2. hikerduane

    hikerduane Subscriber

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    NRV's are the same for the most part. I still have to place the "T" handle of my new tool in a vise, then twist the fount. Worrying if something will break besides the stuck NRV. Many of my 96's are over 100 years old.
    Duane
     
  3. Radler

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    @69T100C
    You are on a good way with your NRV-key.

    If you make a square ¼" drive on the key and place the socket the other way round, you would have a perfect centred, non rising NRV tool which can be driven through the pump-lid-hole. You could easily adapt for different lengths of some pumps by using some washers of suitable size.

    I published this tool about 3½ years ago, hoping, somebody would produce a few of them in a more professional way. I can't, my workshop is in my bedroom. To my disappointment I heard of no results in this direction. Most people seem not to understand, that every force, they use to push the tool down (to prevent rising), has the effect to keep the NRV struck down.

    Most of us meet NRV's which are very old and deformed by previous owners. It does not help to read about the success of those who are able to remove a new NRV with a standard tool.

    Quick Navigation Menu | Classic Camp Stoves


    Best regards
    Radler
     
    Last edited: May 2, 2021
  4. Radler

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  5. LanceO United States

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    FYI, this is the Tilley wrench I received. This thing fits on the NRV lug VERY tightly -- no wobble, no looseness, just a few microns of tolerance. (If the lug had been deformed by a prior tool to any degree, it probably will NOT fit.) It will not slip off once mounted.
    IMG_1312.jpg IMG_1310.jpg
     
  6. hikerduane

    hikerduane Subscriber

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    When you get a 100 or 2 stoves, you'll find they start wearing and a non-rising tool of some sort will be needed. Some NRV's are easy, leading neophytes to believe there is no problem.
    Duane
     
  7. 69T100C

    69T100C United Kingdom Subscriber

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    When i posted my first response on this thread, i had no knowledge of the existing problems faced by many.
    I did not intend or want to offend the "Greater Good".
    Looking at the two shown examples of non rising NRV tools, i can appreciate the thought and engineering processes that went into both.
     
  8. hikerduane

    hikerduane Subscriber

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    Myself, I'm just saying that usually just a tool like was mentioned is all that is needed, especially if only needed once. Many examples can be researched by members, just what can one come up with for parts or ability.
    Duane
     
  9. JP2

    JP2 Subscriber

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  10. 69T100C

    69T100C United Kingdom Subscriber

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    Thanks for the link, there’s so much information within this website :thumbup:
     
  11. snwcmpr

    snwcmpr SotM Winner Subscriber

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    A point I think is important is that sometimes the NRV is stuck so hard that a better tool will allow you to turn hard enough to break the bottom of the pump tube.

    Penetrating oil can sometimes help to reduce that force required. Hot water in the tank is another possibility.
    There is a lot written about removing a stubborn NRV.
     
  12. Radler

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    @snwcmpr

    The torque of the tool can not break the pump bottom. The NRV part in the the key would break off before.

    The problem is the force you apply to keep the tool down. This force goes to 100% on the bottom of the pump and can break the soldered joint. It also counteracts with your intention to move the NRV upward, when you have to press the tool downward at the same time.

    A non-slip NRV-tool does not apply any force on the pump bottom, except the torque. This is the secret, why a non-slip tool is much better and safer.

    Radler
     
  13. LanceO United States

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    Thankfully, I had a young Optimus 111 -- only 42 years of frequent use. To think the original NRV went that long, well, good stuff. Fifty years ago in Bolivia, I cooked daily on Primus kerosene stoves. And at that time, I had no idea what an NRV was.... The problem was just keeping something on hand to clear the plugged jet, which was a common daily problem with the fuel at hand.

    One other aside: I changed to using Coleman white gas in the stove around 1985. The Optimus dealer told me I only needed to change out the jet, and gave me one. I can say it has worked splendedly for many years. So is that the only difference between a 111 and at 111B -- the Optimus dealer told me it was back around 1984.

    When the NVR did start leaking a couple years ago, it did flame out the pump tube a bit, and was obviously a "wee bit" dangerous. But the leak was not massive. If I had the thing in a tent with that leak (as I often did in prior decades), it would have been a bad scene. My daughter just threw it in the lake, having a lake conveniently a few feet away.

    But so it goes. Most of the time now I am in the desert with it, and if flames out, I will step back, watch the fireworks, and eat a cold dinner.... I will trust the new NRV, be calm and carry on, with a careful eye to the possibility of another leak.
     
  14. snwcmpr

    snwcmpr SotM Winner Subscriber

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    Ok, if you say so.