M1950 - SMP 1982 (Box dated 8-84)

Discussion in 'Military' started by snwcmpr, Jan 13, 2012.

  1. snwcmpr

    snwcmpr Subscriber

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    While visiting in Southern California, I found a posting on Craigslist.
    Drove over and got a brand new in box M1950 with (2) copies of the technical manual.
    40 USD.

    1 question:
    How is the lower pump cap properly threaded on so that the upper pump cap properly seats?
    The manual mentions to be sure the pump tube gasket is seated properly after attaching the lower cap. It came properly seated.
    Where do you thread the lower cap to be in the proper position for the upper cap to ensure sealing properly?
    If you own one, I think you will know what I mean.

    Thanks,
    Ken

    Here are 4 photos I took today.
    1326497473-M1950__0__001_opt.jpg
    1326497484-M1950__0__002_opt.jpg 1326497494-M1950__0__003_opt.jpg 1326497503-M1950__0__004_opt.jpg
     
    Last edited by a moderator: Jun 27, 2015
  2. itchy

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    I don't have one in front of me, so I don't want to say something that is wrong -- but the directions make it sound more confusing than it is. Give it a try and it will make sense.
     
  3. toonsgt

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    The upper and lower caps screw together snug and then act as a single unit. An odd design, but it works. Since it's new and an SMP, it may need to be broken in a bit. But once it is, it should be fine.

    Don't go fueling it up until you do a pressure test first. The NRV at the bottom of the pump tube is an area of higher than average maintenance(CRAP design) compared to the permanent Coleman pump tubes. But once it's sealing well it is ok.

    I could go on and on, but there is a TON of information on these stoves here. Read up on it. It's a really neat, dependable unit.

    Mike
     
  4. snwcmpr

    snwcmpr Subscriber

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    Thank you,
    I did tighten and loosen it a few times.
    It just seemed that there would be a 'sweet spot' to have the lower cap positioned to better attach the upper cap to it. Like if the lower cap is too high, will the upper cap still seal, or vise versa.

    When I get home, I will test it, take apart the NRV, and possibly (??) light it.
    I've never had an unlit stove I didn't light.
    Never saw the purpose, till now.

    Ken
     
  5. toonsgt

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    The caps don't seal on these. The seal is on the rim of the pump tube. The two piece cap allows you to take the pump apart if you need to, yet be captive to the pump so parts don't get lost while refueling.

    Again, unless something is wrong with it, the pump tube slips into the lower ring holds the top cap and pump captive. Snug ring into the cap and just tighten both down on the filler neck as a single unit. The seal in the pump tube lip/rim will seat on the rim of the filler neck.

    Mike
     
  6. RonPH

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    I agree with toonsgt. One thing I noticed is that the thread on the outer cap is so fine (and shallow) that it takes a certain technique (or sweet spot as you put it nicely) to close the cap thus sealing and keeping the pump tube firmly in place.

    Forcing the cap which is not properly in the grooves will deform the threads on the cap eventually.

    Congratulations on your recent acquisition :thumbup:

    Ron
     
  7. HercL4D2

    HercL4D2 Subscriber

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    I still have 2 left from a lot of 10. All 1950 dates new in box, sealed in military plastic.

    DSC00669 - Copy.JPG