Is This Dangerous, or Am I Just a Nervous Nellie?

Discussion in 'Stove Forum' started by E.B., Dec 12, 2019.

  1. E.B.

    E.B. Subscriber

    Offline
    Joined:
    Jan 19, 2017
    Messages:
    14
    Location:
    Kittery, Maine, USA
    I had an issue and was conversing with Doc Mark. He gave me some great suggestions, but also recommended that I post my question to a wider audience, so here goes.

    I got an excellent deal on a 1974 Coleman 413G which I was going to part out on another 413 and other stoves. Of course, I had to try it after a little minor cleaning (blew out manifold and aux. feed tube and flushed tank out) and testing (oiled leather, verified check valve held and filler cap gasket was good). When I attached the tank, I did notice that the generator entered the manifold at somewhat of an angle.

    7940DB05-22D0-4B87-B241-CB9DDF8B920B.jpeg

    It lit right up and burned brightly with no fuss at all, but I could hear random very soft pops from time to time. I assumed there was a small amount of fuel in the manifold that was igniting, so I shut it down to empty it out. Nothing came out.

    I re-lit it and ran it for approximately 20 min with no change. There were soft pops the whole time. The flames were blue and steady the entire time with no flare up or sign of excessive fuel.

    I don’t recall hearing this popping with my other Colemans.

    Thoughts?
     
  2. snwcmpr

    snwcmpr Subscriber

    Offline
    Joined:
    Nov 16, 2011
    Messages:
    13,022
    Location:
    North Carolina
    Do you have it turned all the way up?
    Does it do it if you back off?
    Does it do it if you light the second burner?
    You may be giving it too much fuel for one burner.
     
  3. E.B.

    E.B. Subscriber

    Offline
    Joined:
    Jan 19, 2017
    Messages:
    14
    Location:
    Kittery, Maine, USA
    Snwcmpr,
    I was thinking similarly to you, but “throttle” position and second burner made no difference.

    Doc Mark suggested that since the generator is not aligned longitudinally with the manifold, maybe the proper mix is being disrupted.

    I am going to do a proper tear down and clean, then align things upon reassembly. This is what I should have done to begin with.

    BTW, I attached the tank to my 426D and it functioned flawlessly, so the issue is definitely within the 413G.

    I appreciate your response, EB.
     
  4. Jim Lukowski United States

    Offline
    Joined:
    Jul 13, 2015
    Messages:
    148
    Location:
    New Jersey, USA
    When you state that you blew out the manifold, if you only used a compressor and there were spider webs in there, they probably still are. I would at least ream out that burner tube with a wire or cable tie.
     
  5. E.B.

    E.B. Subscriber

    Offline
    Joined:
    Jan 19, 2017
    Messages:
    14
    Location:
    Kittery, Maine, USA
    Jim,
    Excellent idea! I guess I was just too impatient to see what exactly I had hauled home...
     
  6. snwcmpr

    snwcmpr Subscriber

    Offline
    Joined:
    Nov 16, 2011
    Messages:
    13,022
    Location:
    North Carolina
    Spider webs are the most likely cause. Nasty buggers like to crawl in there.
     
  7. geeves

    geeves New Zealand Subscriber

    Offline
    Joined:
    Sep 29, 2009
    Messages:
    5,226
    look around the manifold entry point for a small flame when it pops. My 533 does this around the bottom of the burner due to surface corrosion causing a bad seal bad its only cosmetic so wont be fixed
     
  8. presscall

    presscall United Kingdom SotM Winner Subscriber

    Offline
    Joined:
    Aug 25, 2009
    Messages:
    8,720
    @E.B.
    Your photo’s a good shot and reveals, to my eye at least, that the ‘square’ part of the mixing chamber is out of alignment with the rest of the metal pressing. How can that be I wonder?
    If that’s so it’s unlikely that loosening the mounting screws and attempting to align the components will work.
    Those spiders have been working out somewhat to knock that mixing chamber out of shape!
     
  9. ArchMc

    ArchMc Subscriber

    Offline
    Joined:
    Jul 25, 2004
    Messages:
    2,742
    Location:
    Mojave Desert, California
    While I think it's always a good idea to check for spider webs and such, it looks like the manifold is out of square. I'm going to second (third?) that proper mixing is disrupted. It may be that some of the spray is hitting the side of the manifold and the pops are actually small explosions as liquid fuel collects and ignites. I think your plan to try to carefully realign it is a good one. It's just pressed sheet metal, so check for cracks and separation before you relight it.

    ....Arch
     
  10. E.B.

    E.B. Subscriber

    Offline
    Joined:
    Jan 19, 2017
    Messages:
    14
    Location:
    Kittery, Maine, USA
    Well, the verdict (at least in my mind) is in.
    Spiders - 0
    Mixture - 1

    I tore things down and did a thorough cleaning. The manifold and aux. feeder were clear. I even pushed a cable tie through with a piece of string attached. I then tied a wad of rag to the string and hauled it back through to be sure. Still soft popping.

    A close inspection of the manifold showed definite out of line mixing chamber. Unfortunately, the parts are welded and quite thin material so I was very reluctant to reef it back where it belonged. Instead, I bent the manifold mounting tab on the back of the case to the left (and therefore the manifold itself), then I tweaked the valve/stem assembly on the top of he tank to the right a couple degrees. The result was a much better alignment of the generator with the back of the manifold. As Doc Mark suggested and presscall posted (and Arch seconded), the issue seems to have been a mixing issue, because now it is a thing of the past.

    Thank you all for helping me to figure this out. You guys are the BEST!
     
  11. Doc Mark

    Doc Mark Subscriber

    Offline
    Joined:
    Dec 12, 2004
    Messages:
    16,998
    Morning, @E.B. ,

    Glad you posted this here. One man's opinion, even if correct, is still just one man's opinion! As you can see, we've a ton of good Stovies here, eager to lend their experience and suggestions!! Glad that we were able to help out on this! As Grandma once said, "I'd rather be lucky, than good". Hummmm.... I know know, Grandma! I would rather be lucky AND good!!! From our mouths to Gods Ears!!! Take care, and God Bless!

    Every Good Wish,
    Doc
     
  12. Jim Lukowski United States

    Offline
    Joined:
    Jul 13, 2015
    Messages:
    148
    Location:
    New Jersey, USA
    Good job and thanks for the update.
     
  13. snwcmpr

    snwcmpr Subscriber

    Offline
    Joined:
    Nov 16, 2011
    Messages:
    13,022
    Location:
    North Carolina