Optimus 8r first trip

Discussion in 'Stove Forum' started by Tez, Mar 15, 2026.

  1. ArchMc

    ArchMc SotM Winner Subscriber

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    I still think this sounds like a leak somewhere. Have you done the dunk test?

    I've only used the pump per the early '70s instructions. Caveat with those is only to give a couple of pumps with the stove 3/4 full. The idea is to create about the same amount of pressure in the airspace as will occur with normal heating.

    Another thought: Is the burner bell tightly screwed onto the valve assembly? I seem to recall another case like this where the threads didn't mate well, and there was insufficient heat transfer to the tank. But with that pot on the stove, I would think there's enough heat going to the tank.

    ....Arch
     
  2. itchy

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    Good suggestions by Arch. And prompts another -- what happens if you use a slightly larger diameter pot, the idea is to reflect more heat. Usually, the advice is to avoid prolonged use with a large fry pan due to too much reflected heat.

    Finally, has the source or type of fuel been mentioned/discussed already? The last video -- those spurts of yellow or red flame have sometimes been attributed to moisture contamination.

    note: in case I wasn't clear -- I would not trust the accuracy of the ChatGPT history I posted above. I was just having fun with it.
     
  3. Tez United Kingdom

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    Well thank you everyone and I am going to feel like an idiot here but that lack of pressure after 20 minutes or so was caused by low fuel :)
    If run flat out from the level I was using around 3/4 the level dropped down just below the pipe.
    Also the fuel I am using system 20 s200i/5 fast drying when compared with a tank of petrol the petrol gave 3x the roar and boiled water quick as hell. During the same 20 minutes and even burned a bit longer and hit 23-24 minutes. So going to try another fuel as apparently petrol is not recommended
     
  4. hikerduane

    hikerduane Subscriber

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    Many times issues are from the user, not the stove or lantern.
    White gas/Coleman Fuel\camp fuel etc.
    Duane
    PS: Also, running a stove that uses a wick can scorch the wick if it runs out of fuel, but I have only read that may be the cause for a wick showing blackening near the burner.
     
    Last edited: Mar 18, 2026