Optimus 8R fuel cap problem

Discussion in 'Stove Forum' started by jkline, Sep 28, 2016.

  1. jkline

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    Hi all,

    My mini pump compatible fuel cap won't hold pressure. Replaced the gasket. The spring still works in the male part of the cap. I don't have a pentagonal wrench, so didn't mess with the female end. Anyway, hate to throw the cap away, so thought I'd solicit repair suggestions. Thanks, Jeff
     
  2. tofta

    tofta Subscriber

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    This little masterpiece have two seals, an ordinary pip in the NRV part and an o-ring in the SRV part. This o-ring sits around a funnel shaped little thing moving from the SRV spring action. The spring is seated in the bowl of the funnel and against the screw on top. The SRV o-ring seals against a seat formed by the cap itself. The NRV pip seals against the end of the funnel tube.

    I think this post should be a good starting point. Others might have more.

    I might have a source for those o-rings. Give me a hint if needed.

    You will need a proper tool to get into the SRV. There are also usually some sort of thread lock.

    All the best, e ….. and never throw away stove parts!
     
  3. jkline

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    Thanks. Any idea where I can find a 'pent' wrench?
     
  4. ROBBO55

    ROBBO55 Subscriber

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  5. theyellowdog

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    You can make one easily, file a bit of round metal, or grind a screw driver / Allen key.
     
  6. Funfundfunfzig

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  7. snwcmpr

    snwcmpr SotM Winner Subscriber

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    @jkline
    Don't be misled to think that the 'torx' tool, said to work with this 5 sided screw, will work. It will, most probably, bugger the hole. Use a proper 5 sided tool, or make a proper tool.
    As a side note: The original tool, designed by @exeter_yak had a taper designed into the 5 sides.
     
  8. Doc Mark

    Doc Mark SotM Winner Subscriber

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    @jkline

    +100 on what @snwcmpr wrote. "Make do" tools are rarely super effective, and even if they do work, they usually damage some other part, such as Ken mentioned. Good luck, and God Bless!

    Every Good Wish,
    Doc
     
  9. Longilily

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    We deliberated over this taper on the FB penta key for some time, whether or not to apply it to our tools (It's easily done), but we thought it better (in our opinion) to have more 'Surface Contact' to drive the screw with a parallel drive, rather than a taper drive with considerably less surface contact.
    The taper is a good idea to 'Fit all' though :thumbup:
     
    Last edited: Oct 1, 2016
  10. JonD

    JonD United Kingdom Subscriber

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    I suggest the taper is a bad idea. It will have little contact area and will try to split the brass at the top corners - exactly the weakest point. Asking for trouble. The exact fitting tools such as made by @Longilily are the only thing I would use for this.
     
  11. snwcmpr

    snwcmpr SotM Winner Subscriber

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    @exeter_yak must have had reason and I am not qualified to debate it.
     
  12. jkline

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    Thanks guys. I got out my stash of new pump caps I bought from A&H a few years ago. All leak through the end of the cap... all four. Guess I better buy a pent wrench... this is ridiculous.
     
  13. Longilily

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    Maybe, but at least when you've serviced your caps, you'll be confident that they'll do the job :thumbup:
     
  14. snwcmpr

    snwcmpr SotM Winner Subscriber

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    Too many years people thought that the SRVs lasted forever.
     
  15. jkline

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    Unused in a bag for five years is not forever. These were not made in the 60's; they were fabricated in 2011, according to A&H. As there is an obvious reliability issue with these, I'll start packing an extra cap in the repair bag.
     
  16. hikerduane

    hikerduane Subscriber

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    I received a Campingo 2 with the fuel cap soldered over. I thought parts might be missing, so sent it off to a master to repair. He just cleaned up the solder and serviced the SRV.
    Duane
     
  17. Longilily

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    keep us Informed of your finds Jeff :thumbup:
     
  18. snwcmpr

    snwcmpr SotM Winner Subscriber

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    I agree. My comment was, not to you personally, but that prior to a few years ago the SRVs were not serviced at all, except by maybe a few. Now, with the information out there it is a simple job to switch out the pip.
     
  19. Longilily

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    Isn't that testament to our community ! Putting our heads together and sharing info/experience and learning together !

    Great stuff if you ask me ! Well done to all of us far and wide :thumbup:
     
  20. SimonFoxxx

    SimonFoxxx Subscriber

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    I am sorry to say I had the same kind of problems as JKLine, with caps from the same supplier. Bluewater Stoves were able to fix them up for me, so all are good now.

    Cheers
    Simon Foxxx
    New Zealand