Manaslu 96 Disappointment

Discussion in 'Fettling Forum' started by Greeley, Jun 7, 2019.

  1. Greeley

    Greeley United States Subscriber

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    Hello all, the used Manaslu 96 stove from the 'Bay arrived in the mail yesterday in what seemed very nice shiny condition, and very shortly I put in some kerosene and fired it up. Primed with alcohol it soon gave out a satisfying roar. But within a half-minute the roar began to subside to a simmer, and needed pumping again to bring it to full flame.

    So I shut it off, let it cool. This morning I gave it the dunk test, found no evidence of air bubbles or leaks anywhere. Fired it up again with same results. Took quite a while to boil a pint of water (I did not time it), and had to pump up pressure six times before it got to a rolling boil.

    Any suggestions? I have a Primus 96 and 210, a SVEA 121 and an Optimus 00, and none of them exhibit this kind of pressure loss. I'm stumped.

    Tom
     
  2. snwcmpr

    snwcmpr SotM Winner Subscriber

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    Re do the dunk test.
    Cold stove hot water.
     
  3. Tony Press

    Tony Press Australia Subscriber

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    It sounds like a leak of air pressure. Do the dunk test with the pump out of the pump tube.

    Tony
     
  4. Radler

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    You can also make an improved test with pump pressure.

    Put a tiny bit of candle wax on the (dry) jet. Melt it with a lighter, it will fill the orifice. Let cool down. Now you can pump to operating pressure and remove the pump rod. Dunk the stove. Look for bubbles.
    If the pump valve is leaking, take out the stove from the water and fill only a very little bit of water in the pump, just to cover the valve. If you see bubbles coming out of the valve hole, the pip is leaking, if they appear from the side, the gasket leaks.
    With this method you can also detect leaks from the nipple thread and fissures in the brass.
    The wax will melt and vaporize when priming the next time.

    Radler
     
    Last edited: Jun 7, 2019
  5. Wim

    Wim Subscriber

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    Nice trick using wax @Radler ! Never heard of it before. Thanks for sharing!

    Best regards,

    Wim
     
  6. Tinus Netherlands

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    Hi @Greeley, if you find no leaks and if the tank released air upon shut off ( could not determine that from your post ), you may have to prick the jet/nipple, many times. With my new Manaslu 96 I had the same problem of a strong flame going down to a small blue flame within a minute with no chance of getting it back to full flame. Some crud or industrial residue was in the burner and partially blocked the jet/nipple. After a dozen times of pricking and lighting the problem was over. Hope this helps. All the best, Tijn
     
  7. Afterburner

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    @Greeley If above doesn't help and you are not happy with your Manaslu 96 many members would be ready to help you to get rid of it. I am sure they are ready to pay P&P also. :!::lol:

    I have had same symptoms with few stoves and tank lid seal or NRV pip replacement has normally solved the problem. With Manaslu 96 one place for leaks is tank to riser and riser to burner joint. 'Dunk test' should indicate where the leak is.
     
  8. Simes

    Simes R.I.P.

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    I'd vote for the 'creeping crud' suggestion myself if dunking isn't showing leaks and there's still pressure in the tank when you shut down. 'Lurking Grollies' are also known to cause problems.
     
  9. Greeley

    Greeley United States Subscriber

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    I could not find any leaks even with several dunk tests, and was about ready to consign it to the 'bay and get rid of it when I had a Eureka moment.

    My ancient Primus 71 suffered from very low pressure and I knew it was the filler cap seal, so had ordered some from Fettlebox. Since replacing that solved the 71's problem I thought hmmmm, maybe on the Manaslu?

    So I replaced the filler cap and -- great results! Maintains nice steady flame!

    Now for the other issue - the flame is quite orange, not blue. Previous owner said he used the stove "quite a bit", so I am wondering if replacing the jet is in order? Does the Manaslu 96 use a standard jet? What size would the orifice be?

    Thanks to all.

    Tom
     
  10. Tinus Netherlands

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    Hi, nice that you resolved the Manaslu mystery. So was it a leak afterall, sort of?

    An extensive review on the Manaslu 96 by @presscall , also on the jet and steel flame ring:
    Manaslu 96

    Tijn
     
  11. Tony Press

    Tony Press Australia Subscriber

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    Tom

    My Manaslu 96 pricker is 0.30mm in diameter, so the jet would be a standard 0.32mm jet.

    I don’t worry too much if the tips of the flame are a bit yellow. My test is whether the stove leaves wipeable soot on the bottom of the pan.

    Cheers

    Tony

    @Greeley
     
  12. JP2

    JP2 Subscriber

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    Hi
    Any pictures of the yellow flame? I would love to see a Manaslu 96 running. Never seen one before.
    Thank
     
  13. Tony Press

    Tony Press Australia Subscriber

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    Mine is unfired.

    Tony
     
  14. Ed Winskill

    Ed Winskill United States Subscriber

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    Behold:

    [​IMG]
     
  15. afoton

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    It is not the same threads. So a Optimus/Primus jet will not fit.
     
  16. JP2

    JP2 Subscriber

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  17. JP2

    JP2 Subscriber

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    @Simes
    Hi
    What is, Lurking Grollies? I don't know what that means.
    Thank
     
  18. Tony Press

    Tony Press Australia Subscriber

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    @afoton

    I’d forgotten that the threads are not compatible between the Manaslu nipple and the standard Swedish thread.

    But we do have a terminology issue: I always refer to the hole that the vapour is emitted through as the “jet”; and the piece of brass that the jet is drilled in as the “nipple”.

    Cheers

    Tony
     
  19. Simes

    Simes R.I.P.

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    @JP2 Bit of a Brit term for random small bits of rubbish. I was using it in this instance to suggest there could be some small bits of dirt in or around the burner. Pricking the jet just pushes them back in to then come back and partially blovk the jet all over again. It can be an infuriating issue to clear up.
     
  20. ArchMc

    ArchMc SotM Winner Subscriber

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    Take the nipple out and pump the stove so fuel will force the bits out.

    ....Arch