1/4 copper fuel line fitting

Discussion in 'Identification' started by robint, Oct 11, 2012.

  1. robint

    robint New Member

    Can anyone tell me the origin of the fitting used to connect the cu fuel line to the fuel tap and carb as used on a Lister D but also quite common on prewar machinery. The joint has a 1/4 nipple with a shallow cone seat (something like 25deg). This is soldered onto the 1/4 cu tube and the whole lot is clamped with a 1/4 bsp nut. Its a common fitting which i guess we all take for granted (till you havent got one). Where does it come from, whats it called, whats the design standard?
  2. Numpty1

    Numpty1 Member

    Try a vintage car specialist. You will pay the earth but they are available. Alternatively I think Rattlenackers on Ebay sells them. If you are anywhere near Oxford area, Enstone bring and buy on the 10th November is another good place to try, search Cotswold Oil Engine Society for details.
  3. lambe

    lambe Member

    Go and see your local Pneumatics dealer , quite few still stock solder olives and nuts
  4. robint

    robint New Member

    I was put on to a useful supplier of old bits who makes replica parts
    http://www.vintagecarparts.co.uk/produc ... ipe-nipple
    for those who are interested

    and, of course I can knock these up on my lathe easily (although the bsp nuts would be a bit more tricky).

    What interests me is where this design came from, whats its official description? Is there an acknowledged standard (must be surely?)

    The pic of the 3 way valve was said to have come from a DK and switches from petrol to paraffin but it differs from photos I have seen (on the back of the excellent Lister D history book) and also has a seat angle of 130deg which doesnt match the 55 deg angle of the nipple. Also the throat is too narrow at 10mm vs the nipple which is 11.2m

    So this is an odd tap but old, maybe war issue?

    All good fun


  5. boat_man

    boat_man Member

    Imperial Wade compression fitting nuts are BSP & readily available.

  6. robint

    robint New Member

    Hi Jim
    I enclose some pix of the offending fitting. I wonder whether the Wade nut would accept the width of the nipple, or do you have to drill the nut out?

    I have seen the other solution from Vintage parts. Its a recent commercial product but I can't remember the name to the manufacturer (used for pneumatics I seem to remember)

    IMHO, I dont like to see an engine with an obvious mixture of fittings or sprinkled with modern replacements. I dont think it would suit museum purists.

    I found this
    nut and nipple for $9 form an Italian Motto Guzzi specialist which seems closer to the original, but notice its a bullnose fitting.

    The plot thickens - see photo

    I think I may end up making my own copy :roll:
  7. boat_man

    boat_man Member

    Yes you would have to drill out so it bears on the shoulder behind the cone - thought it would save making a nut !

  8. Victoria

    Victoria Member

    I somehow think the Lister etc fuel line nuts and solder-on nipples were made by Simplifix and I believe they were bought out by Wade. The hex nuts for solder-on types are different to the ones for the later compressed-olive type in having a flat seat inside, whereas the later ones have a cone or countersink in them to accept the olive and make it fuel/air tight. You can, if you are lucky, drill them out to suit the body diameter of the nipple, leaving sufficient flat seat. The modern Wade ones have a turned portion in the hex and do not look right. When I worked in engineering, the solder-on nipples became unobtainable and we used to make them in batches - a nice job for the apprentices on the capstan. The best bet, as someone said, is to try a vintage car speciallist and be prepared to pay a premium to get the correct things.
  9. robint

    robint New Member

    HI eric
    Thanx for that info, its all coming together. The hex nuts can be made from 1/2in hex brass bar, I have ordered some. I too remember my apprentice days in the machine room on a capstan (Ward). these fittings were often used on prewar motorcycles and early post war (BSA Triumph etc).

    I found this, you can recognise the nut design.
    http://www.flightglobal.com/FlightPDFAr ... 202408.PDF

    There doesnt seem to have been any design standard associated with what I can a cone seat solder nipple. A version of an black iron cone seat union still exists in plumbing circle today
    A 1/4in screwed nipple connector was used on domestic gasfires on the final length between the gas cock and the fire (though I remeber the thread was much finer than bsp, probably bsf.

    Well, there's restorers and bodgers


  10. campingstoveman

    campingstoveman Active Member


    The one name you havent mentioned and I've used is "Enots", I buy my fitting from Marine Chandlers also.

    Martin P
  11. highrange

    highrange Member

    I seem to recall that Enots did a lot of chassis lubricators etc for commercial vehicles in the dim'n'distant.
  12. robint

    robint New Member

    Care to say which marine chandlers? :lol:
  13. campingstoveman

    campingstoveman Active Member

    It was local to me but found out recently they have gone but cant see why others cant help you.

    Martin P
  14. Victoria

    Victoria Member

    The engineering industry went over to mainly ENOTS ( Made incidentally by Benton & Stone and thus ENOTS is STONE backwards) and they are very different fittings to the ones used by RA Lister. The nut is a special metric internal thread - good fittings but not to replicate early Lister engines to original standard. There are different style nipples for plastic or for copper pipe. My former oil-fired CH boiler used Enots fittings.

    Should be easy enough to make the nuts, use a nice sharp new bottoming tap and even shove a two-flute cutter up first to make a flat bottomed hole; and certainly the solder-on nipples are simple enough. At U of B we made the nipples in their thousands in a few differering sizes and reused the nuts.
  15. petternut

    petternut Administrator

    I make my fittings but for only £8 you an buy a new Lister D fuel pipe with the right fittings from Mac McGowan who trades on Ebay as rattlenackers (sic).

  16. robint

    robint New Member

    Yes indeed, a faithful reproduction of a Lister D fuel pipe from a quality supplier, and whose photo I first showed, then I started digging into the origin of these cone seat fittings and discovered how little was known about these once ubiquitous fittings. I do have other bits of piping to do as well which I want to resemble the period

    My researches have shown that the fitting may have come from the Enots stable (also made fuel taps)


    btw, here is a useful compilation of threads


    Notice 1/4 gas thread No4 has 27tpi which I have also seen on petrol taps

    I think that these fittings may have provided a sound mechanical connection proof against vibration, but may not have been so good at sealing. Slightest imperfection or dirt on the seat would cause problems. The industry went on to discover the value of sharp metal edge joints (eg the development of the bullnose widely used on gas bottles for example) and the compression fitting which was called a bite type seal and may have been pioneered by Ermeto in Germany in the 30's as a development of the stuffing box concept (only they p[ut a gripper ring inside to stop the tube blowing out. They probably stumbled upon the case where the tube had sealed even though the stuffing had been forgotten. but it only became generally accepted in the 50's in the uk.

    Notice the similarity in the tube nut.

    http://www.hfifluidpowerproducts.com/co ... tings.html

    I remember from my biker days, that these cone seat fittings could be temperamental (as were the bikes). They had to be tightened just right right, but there was a tendency to over tighten particularly with old much used fittings and damage the nut. The slightest looseness and the joint would weep (just like petrol taps). There was no give in the joint

    I was wondering whether a suitable compromise might be a 55deg well angle mating with a 54deg cone angle (rather than a bull nose say which is more difficult to specify). Then you have a wedge circular seat mating.
    It would still be otherwise authentic but have more give in the coupling.

    I will knock one up and try it on some old taps, and of course it will have to be compatible with metric 6mm cu tube rather than 1/4" not generally available now



    PS Im going to start another thread on Taper plug valves (fuel and water for the use of) :roll:
  17. petternut

    petternut Administrator

    Attached is a table you may find useful. Its an early find amongst the Petter drawings though the nuts haven't yet turned up.
    At the present rate of progress I estimate I'll still be indexing when I'm 92 which may be well after my sell-by date :)

  18. robint

    robint New Member

    I suppose it makes sense that Petters would make their own couplings, simple job for an apprentice on a belt driven Ward capstan (as I remember - that smell of mistic mixed with cold tea slops in the suds tray)

    So a pt no for a 1/4 nipple would be SD-2/2
    We need drg SD-4 for the nuts

    Herewith a png as this board doesnt display Tif's


  19. petternut

    petternut Administrator

    I'm suitably overwhelmed. Don't hold your breath waiting for the nuts drawing.

Share This Page