Dudeland Posted November 15, 2017 Share Posted November 15, 2017 I searched all over the forum and never found the answer, so I thought I would document it here. The input on a Weber 32/36 (with a threaded fitting on the end) is a 1/8 -27 NPT fitting. How do I know... i spent some time at Home Depot and the at Canadian Tire today going through the dies and taps. I happened to have a spare lid off an old junk carb that I could use. The interesting part is that the threaded bore seems to be tapered quickly, so if you put in a 1/8" pipe fitting you get two threads in and then it starts to bind... but if you match the bolt to a die, it goes on perfectly. So if you are running AN style fittings for your fuel delivery hose to your Weber, you need to get a 1/8" to -6 or -4 AN line. I will post pics once I have my line installed. As always use Teflon paste, not tape, to seal between the 1/8 fitting and the carb (if you feel you need to). Quote Link to comment Share on other sites More sharing options...
02Les Posted November 15, 2017 Share Posted November 15, 2017 Assuming the carb was manufactured in Europe, I would have thought the thread would be 1/8" bspt. Finding NPT fittings overseas can be as rare as rocking horse droppings. Quote Link to comment Share on other sites More sharing options...
Simeon Posted November 15, 2017 Share Posted November 15, 2017 (edited) BSP will be correct. The 'few turns and then stops' is the common sign between the two. More info: https://www.valvesonline.com.au/references/threads/ Edited November 15, 2017 by Simeon Quote Link to comment Share on other sites More sharing options...
Dudeland Posted November 15, 2017 Author Share Posted November 15, 2017 F'n shitty. How the heck do I get a 1/8 BSP to 6an fitting? And why did the die fit on the bolt? Quote Link to comment Share on other sites More sharing options...
Dudeland Posted November 15, 2017 Author Share Posted November 15, 2017 Ok I found one in Japan. We will see if it fits when I get it. Quote Link to comment Share on other sites More sharing options...
tahoedon Posted November 15, 2017 Share Posted November 15, 2017 Pegasus Racing has a 1/8 bsp male to 4AN male, part no. 3230-2-4AN Quote Link to comment Share on other sites More sharing options...
'76mintgrün'02 Posted November 15, 2017 Share Posted November 15, 2017 33 minutes ago, Dudeland said: why did the die fit on the bolt? (( I am waiting for the punchline )) " BSPT (British Standard Pipe Thread) is similar to NPT except for one important difference. The angle across the flanks of threads (if you sliced the fitting in half long-ways and measured the angle from root to crest to root) is 55 degrees instead of 60 degrees as it is for NPT. " 1 Quote Link to comment Share on other sites More sharing options...
Dudeland Posted November 15, 2017 Author Share Posted November 15, 2017 I know I just looked up the same article. That is why the bolt would go into the Die, Anyway. I learned something new today. I wonder if anyone else is looking for this info? Maybe I should corner the market LOL!!!!! Quote Link to comment Share on other sites More sharing options...
TobyB Posted November 15, 2017 Share Posted November 15, 2017 BSPT, Tom, isn't that British Standard Pipe Taper? Like NPT is National Pipe Taper? t Quote Link to comment Share on other sites More sharing options...
Simeon Posted November 15, 2017 Share Posted November 15, 2017 4 minutes ago, TobyB said: BSPT, Tom, isn't that British Standard Pipe Taper? Like NPT is National Pipe Taper? t It is. British Standard Pipe (Taper or straight) was chosen as the 'European standard' and even erroneously called a metric pipe thread. In Australia we even have BSP threads applied to metric sized pipes (internal diameter) - very confusing Quote Link to comment Share on other sites More sharing options...
Dudeland Posted November 15, 2017 Author Share Posted November 15, 2017 I once read that the thread was some "crazy metric thread" but I dismissed it as nonsense. Now it makes a little more sense. I just wish I didn't have to wait until Dec to get a fitting. Quote Link to comment Share on other sites More sharing options...
jireland2002 Posted November 15, 2017 Share Posted November 15, 2017 Just run a 1/8npt tap into the hole and you're good. If you are going to use an aluminum AN fitting you must support the braided hose or it's weight will fatigue the fitting and it will break and probably set the car on fire. It is actually better to just use a hose barb and rubber fuel hose. Quote Link to comment Share on other sites More sharing options...
Healey3000 Posted November 15, 2017 Share Posted November 15, 2017 And then there's BSW - Whitworth... Quote Link to comment Share on other sites More sharing options...
Dudeland Posted November 15, 2017 Author Share Posted November 15, 2017 Crazy... I don't know what other experiences are with running a 1/8 NPT tap, but from what I can find BPT has a different pitch than NPT. I have an -6 to barb that I will run until I can get the BPT to -6. NPT is 27, BPT is 28. Quote Link to comment Share on other sites More sharing options...
Simeon Posted November 15, 2017 Share Posted November 15, 2017 Having spent a bit of time googling it the only references to the threads on Weber inlets are M12 for the banjo inlets on side drafts and down drafts such as the IDF and M10. These are all shown as parallel threads with a crush washer. Could it be an M10? Quote Link to comment Share on other sites More sharing options...
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