Help find a source for 1/4 inch straight pipe thread fitting

[Robert Bergeron]

Hi all . I am finished installing my second gas tank in my MKII Carrier . I need this fitting . The threads are straight not tapered like in today’s cars and trucks . Went to the hardware store , NAPA store , truck repair shop and machine shop. Thanks for your insight guys. Cheers. Bob

[Paul Singleton]

I am not familiar with carriers, but it looks like a standard compression fitting. If it has a ferrule it would be a compression fitting, if it has a flare it would be probably an SAE fitting. SAE is still used on oil burning furnaces.

[Jordan Baker]

I beleive you want these fittings. They are solder on pipe nipples with nuts.

I can’t remember if you need the 1/4” nipple for 1/4” BSP with 1/4” tube or 5/16” tube. The nipple and nut stay the same but the tube can be different sizes.

https://www.vintagecarparts.co.uk/pr...nut-and-nipple

I also used these fittings for hooking up the oil cooler lines. Although I think they were sized for 1/2” tube.

Last piece of advice when making these lines up. Put the nut on with the female end facing towards the end. Then solder on the nipple. If you forget the nut it’s easier to fix then the flared fittings.

[Lynn Eades]

I think they are called Rotherham fittings? (read Rotheram)
I believe the Brits set their sizes by the pipe orifice size,(about volume of flow, cross sectional area etc) so for a pipe with a 1/4" bore the fittings will be designated 1/4"
Someone can tell me if I am mis-leading?

Edit: there does not seem to be any support for what I thought, from a quick google.

[Ron Pier]

The tube is 5/16" from memory but easy to check so a solder nipple and a 1/4 BSP nut.
Available from here in UK
https://www.vintagecarparts.co.uk/pr...nut-and-nipple

or here.
https://www.gsparkplug.com/fuel/copp...ose-connectors

Ron

[Robert Bergeron]

Thank you Paul , Jordan , Lynn and Ron . Mystery solved thanks to you guys. Now what is the fitting that goes on the fuel tank selector valve please ? Stay safe ! Cheers. Bob

[Robert Bergeron]

Hi again and thanks for the replies . What fittings goes in the selector and a source please ?

[Ron Pier]

It was a long time ago when I did mine, but from memory it's all 1/4 BSP. Gas or Pipe threads are confusing because as already stated, the size ie 1/4" refers to the size of the pipe. The actual outside diameter of the 1/4 BSP thread is 1/2".
I had SS braided fuel hoses made up with male ends and 1/4 M&F fittings in the change over valve. Search through the Green Spark plug site for ideas. Ron

[Robert Bergeron]

Thanks very much . is it 1/4 inch BSP parallel or taper ? I had / have no clue of these British specific pipe / thread / sizes . The gas tank fitting threads look to me like they are parallel but i prefer to ask to be sure .

Cheers . Bob

[Ron Pier]

I can't remember if the valve threads are tapered? I got my flexibles made by a local hydraulics hose firm who also supplied the fittings. If you want to make your own with push on hose and jubilee clips or crimps, these would be the simplest system.

1/4 BSP threads x 5/16" (8mm) hose. Ron

[Lynn Eades]

Robert, look at how the fittings seal. If there is a seat of some sort the fitting will be parallel. I have no experience with that valve but the earlier (CO1UC?) valve has special fittings that are BSP/ SAE if I recall. You need to carefully establish what the threads are. The BSP is quite course while the SAE is relatively fine. I hope that helps.

[Robert Bergeron]

Thank you Ron & Lynn . I have everything i need to order now . Very helpful advice ! Cheers .

[Paul Dutton]

From a ‘Brit’ hydraulics engineer, BSP is parallel thread, BSPT is taper.
On the tube we measure the OD (outside diameter) and with hose / flexi we measure the ID (inside diameter) There are a ‘few’ times we measure the ID of tube, but on modern sizes it’s the OD.
As for the nut threads, yes a 1/4” tube can have a 5/16 thread, but normally they are matched. You can get BSP or METRIC in both, pre formed ends or compression olive (ferrule think you might call it in places)
SAE or flared ends as pre forming the tube ends into a flared face, like brake pipe flares etc.
All these are readily available over here if anyone has problems.
Instead of trying your Auto stores or truck places, try the smaller, longer established hydraulic places.
Hope this helps guys

[Robert Bergeron]

Thanks Paul , clear as mud now. Put in an order with Green Spark Plug .... Cheers .