Blow torch "check valves"

Discussion in 'Open Forum' started by j.brown, Sep 13, 2020.

  1. j.brown Australia

    Offline
    Joined:
    Sep 13, 2020
    Messages:
    7
    Location:
    nsw
    Hello everyone. I have some old blow torches ( 1 veritas 'pink'and 2 companions ) I would like to get some new check valves for them. I put some new cork in the valves yesterday and one of them worked for a while but because I bought them partly disassembled I'm not sure I have assembled them correctly. I'd be grateful for any advice . Thankyou.
     
  2. Tony Press

    Tony Press Australia Subscriber

    Offline
    Joined:
    Aug 28, 2012
    Messages:
    6,386
    Location:
    Stinkpot Bay, Howden, Tasmania, Australia
    The check valve (or NRV = non-return valve) on these blow torches should be pretty straight forward, and you probably don’t need to replace them.

    Disassembled they should look like this:

    A765E5A1-0149-4004-B524-611E3ECF1F2D.jpeg

    You will need a lead or HDPE washer here:

    0559CBF8-1677-4878-920D-870CA46E73AA.jpeg


    If your spring is a bit slack, just stretch it about 15%.

    Use good quality cork (not the modern rubberised gasket cork) or Viton to make the pip for your NRV. It must sit flat against the mating surface, and not have grit or dirt.

    Tighten the re-assembled NRV to tight but don’t force it.

    Good luck

    Tony

    @j.brown
     
  3. george

    george United States Subscriber

    Offline
    Joined:
    Nov 8, 2011
    Messages:
    2,348
    Location:
    USA
    All good advice, especially the cork replacement. I had to replace the cork pip in my Petromax 821. Viton just won't cut it!
     
  4. Tony Press

    Tony Press Australia Subscriber

    Offline
    Joined:
    Aug 28, 2012
    Messages:
    6,386
    Location:
    Stinkpot Bay, Howden, Tasmania, Australia
    Well, I have to confess I’ve never had any problem using high quality Viton in an NRV. The trick is to make sure the surfaces are clean and square on, with no grit.

    Cork is a bit more forgiving in that when wet with fuel it will “give” more than Viton does. But good quality cork is hard to come by these days.

    Cheers

    Tony
     
  5. j.brown Australia

    Offline
    Joined:
    Sep 13, 2020
    Messages:
    7
    Location:
    nsw
    Thanks Tony and George, great photos Tony very much appreciated. I really like the idea of the lead washer. I've been trying to make some leather washers with mixed success I think I'll give the lead a go. It might be ok for the fuel cap? The NRVs I have are all a little different. A couple of needle and seat types, the cork / viton type that I guess mates up against the small flat disc on the end of the retainer nut? The other retainer nuts have a stainless steel sleeve fitted in the end. Is this where the little brass mating disc goes? I have Know idea! I just used some cork from a sparkling grape juice bottle for the nut with the disc. I also have a Coleman kerosene lantern model 214A700 I haven't used for many years that still has fuel in it, I don't know if it's ok to leave the fuel in it? Anyway I've gone on too long about nothing of any great importance. Thanks for the feedback it was nice to hear from you.
     
  6. Tony Press

    Tony Press Australia Subscriber

    Offline
    Joined:
    Aug 28, 2012
    Messages:
    6,386
    Location:
    Stinkpot Bay, Howden, Tasmania, Australia
    @j.brown

    A couple of phots from you might help.

    Cheers

    Tony
     
  7. Sedgman

    Sedgman Subscriber

    Offline
    Joined:
    Nov 19, 2012
    Messages:
    258
    @Tony Press
    Companion kerosene blowlamps are generally 1 US pt (Model 42) or 2 pt (Model 43). The fibre washer that fits the pump assembly to tank is between 25 and a max of 27mm OD and 21.2mm ID. You will need to replace the filler cap washer (23mm) and viton is best but any rubber will work for a while but deteriorates quicker. You will need a pricker for the jet.

    The NRV pip is 0.166" diameter and is fundamentally a common size used in Austramax Brand lanterns or even say Veritas 350 lanterns. The lead washer on the NRV is the same as is on common stoves such as Primus, Burmos or Radius ones at about 12.5mm OD and 7.75mm ID. The examples Tony has provided above are excellent and give you the idea of what is involved. The pump tube is a smidgeon under 17mm and the pump cup washers usually come in a small mounted assembly but other equivalents can work too. The fettlebox, advertised top right on this site should be able to assist.

    20200914_203513 - Copy.jpg

    Check for leaks first and check the pump is not rising after you pump it, if it is then you have a problem. Half fill the fount (tank) and then make sure it is WELL preheated and pointed away from your car, just in case. Good luck.
     
  8. j.brown Australia

    Offline
    Joined:
    Sep 13, 2020
    Messages:
    7
    Location:
    nsw
    Thanks Sedgman for the parts information that's really great. I'll definitely order the parts and get some viton o-rings. I wish I knew how to upload photos, as Tony suggested, because I'm unsure of the different NRVs I have. I'll ask someone and try and get that done. Thanks again.
     
  9. Tony Press

    Tony Press Australia Subscriber

    Offline
    Joined:
    Aug 28, 2012
    Messages:
    6,386
    Location:
    Stinkpot Bay, Howden, Tasmania, Australia
    @j.brown

    To upload photos:

    1. Click on the “Upload a File” button at the bottom of the dialogue box.

    99968CC6-99C3-47BE-9889-3DE7C1C6C01E.jpeg

    2. Load your photo from your file.

    3. Place it where you want by putting the curser at that point.

    8C57DC4D-BF0A-4612-9B43-E1AA027954D0.jpeg

    4. Click on “Full Image”.

    328AC447-B46E-4147-AA66-06A394F8AC3C.jpeg


    Cheers

    Tony
     
  10. j.brown Australia

    Offline
    Joined:
    Sep 13, 2020
    Messages:
    7
    Location:
    nsw
    Thank you Tony I shall take some photos and give it a try.
     
  11. j.brown Australia

    Offline
    Joined:
    Sep 13, 2020
    Messages:
    7
    Location:
    nsw
  12. j.brown Australia

    Offline
    Joined:
    Sep 13, 2020
    Messages:
    7
    Location:
    nsw
    Sorry Tony I stuffed up putting the photos up please feel free to delete them. You might be able to see the three different end nuts for the NRVs. One has a brass disc on the end (no air can go through this one! ). Another one has a brass end machined for a needle. And the third one has a stainless steel sleeve through it (a bit sharp on the end) The three brass "pip" holders - one has the cork, another is a machined brass nipple with a thin rubber ring around the base and the last one is a non brass needle. Not to worry I might have to put them back in the shed till I can find some new NRVs Cheers for now.
     
  13. Tony Press

    Tony Press Australia Subscriber

    Offline
    Joined:
    Aug 28, 2012
    Messages:
    6,386
    Location:
    Stinkpot Bay, Howden, Tasmania, Australia
    Over the weekend, I’ll look what I have in my shed...

    Tony
     
  14. j.brown Australia

    Offline
    Joined:
    Sep 13, 2020
    Messages:
    7
    Location:
    nsw
    Thanks Tony but don't worry I'm going to my uncles place he has some in his shed. Many thanks
     

Share This Page