British fuel valve

Jul 18, 2015
74
South P10 Pugetopolis
Our PNW based diesel sloop was built in the UK. We just enountered a problem difficult to repair here. The fuel shut of valve, a size 6 briiish valve, is threaded directly to the original fiberglass tank. Unfortunately the seals have worn out, causing a leak and air in the fuel system. We need a replacment fitting to the tank, to run the line to an inline valve on the bulkhead.

We were unable to locate a replacment or suitable fitting in BC. So we jury rigged a solution ro come back to Seattle. Now that we ar back for the wonter, I want to make a permanent repair. Anyone familiar with the british valve thread and pitch? Hopefully with that info in hand we can purchase or fabricatea replacement.
 

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Jan 4, 2006
7,268
Hunter 310 West Vancouver, B.C.
Anyone familiar with the british valve thread and pitch? Hopefully with that info in hand we can purchase or fabricatea replacement.
Is there any particular reason you would want to stick with such an unorthodox installation? From what I can see in the picture, it appears that you have a bulkhead fitting with what looks to be a less than fuel resistant rubber gasket.

Why not drain the tanks first and then permanently seal the hole (which will be a considerable undertaking). Others may be able provide an acceptable manner. Then install a fitting on the top of the tank with an internal dip tube.
 
Jul 18, 2015
74
South P10 Pugetopolis
The goal is to replace the mcgyver setup pictured, currently mounted on the tank bottom. However ar this time the only item available to fill the hole is the original valve plus a washer.

The priority is the same as you describe; to fill the hole. the easiest way being another fitting or bung with the unique thread diameter and pitch. Niether metric, pipe thread, or other threads fit.

Any idea as to the diameter and pitch for british fittings?
 
Oct 9, 2008
1,742
Bristol 29.9 Dana Point
With the fitting removed, you could use a caliper to measure diameter, and a pitch gauge, which you can get at a plumbing store or readily online. Then you will be able to search with more precision.

Or, you could re-tap the internal fitting to standard threads of a slightly larger size. I'm not saying you should, as I don't know the specs and integrity of the internal tank fitting. I'm just saying you might analyze the idea.

Also, is there a brand-specific forum online for your make of boat? People there might have your specs.
 
Feb 26, 2004
23,049
Catalina 34 224 Maple Bay, BC, Canada
It appears that this take off is in the sump of the tank. The sump is a great idea, but the wrong place for a fuel tap 'cuz that's where all the grunge in the tank will live.

Regardless of how you arrange your new fuel pickup, that's not the place to do it.

OTOH, it IS a great place to use for a tank drain. So when you do empty the tank to replace the fitting, by all means install a new SAE shut off valve there to drain the sump.

Many of us with plain rectangular tanks wished we had this little sump.

Good luck.
 

Apex

.
Jun 19, 2013
1,212
C&C 30 Elk Rapids
check for bspp or bspt: which is very common in all of Europe and can be had here.

BSPP is a straight thread form (aka G thread as well)
BSPT is a tapered thread. NPT fittings are VERY close the the BSPT.
 
Jan 30, 2012
1,144
Nor'Sea 27 "Kiwanda" Portland/ Anacortes
One expects that the thread form is plain vanilla Whitworth - that is British Standard Pipe Tapered. To obtain the correct diameter and thread form visit a hydraulic hose shop They will have a variety of BSP fittings. If not then purchase a suitable stopcock and BSP adapter. If it is a true mystery thread any machine shop can make an adapter.

National Pipe fittings thread form does not match.

As an aside the best idea is to remove it , replace it with a plug or drain cock, and make your fuel dip take off from the tank top as Ralph describes.

Start with Nebar in Ballard and let us know what happens.

Charles
 
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Nov 6, 2006
10,095
Hunter 34 Mandeville Louisiana
May be possible to easily put in new packing at the stem to stop air leakage? Normally, they use a small o-ring which can be accessed by unscrewing the top of the valve (after the tank is drained).
 
Mar 20, 2012
3,983
Cal 34-III, MacGregor 25 Salem, Oregon
unfortunately, the british have several thread/pitch combinations just like we do here. so it would be virtually impossible for someone to tell you what you have without gauging it... short of a very lucky guess.
the valve you have may be rebuildable,as most quality valves are and could last for years again, but if not or you choose to change it to an american type valve NAPA carries some of the most common thread adapters... you can also check with a kubota or yanmar or some other import tractor dealer for these adaptors.
another place to get odd thread adaptors is at a hydraulic shop. one that is a Parker dealer has direct access to all the different common thread styles of the world...
 
Jul 18, 2015
74
South P10 Pugetopolis
Thanks for the information everyone. We are moored near several heavy equipment shops including a shop that fabricate fuel and hydraulic lines and so I'm confident we will come up with a replacment part during our spring haulout.

I'll be sure to update this topic once the repair is complete.
 
May 24, 2004
7,174
CC 30 South Florida
I guess having an accesible drain plug facilitates maintaining a clean tank. The small sump even perhaps guarantees that almost all of your tankage is usable. If it has been working fine and no problems with clogging then get online with a UK chandlery or plumbing outfit to find a replacement.
 
Apr 8, 2010
2,120
Ericson Yachts Olson 34 28400 Portland OR
Is that a little gate valve? If so, drain the tank and replace it with a new quarter-turn ball valve. You might want to run new USCG-approved fuel hose all the way to the barb fitting on that new valve, while you're at it.
(been there, done that, alas, no T shirt... no fuel problems, either... !)
:)

ps: what kind of boat?
 
Jul 18, 2015
74
South P10 Pugetopolis
Yep, we will pump out, head over to the local Truck/heavy equipment shop to locate a barb fitting for the new inline quarter turn installed this summer. No one on the sunshine coast could come up with a new fitting, hence the message. We will trade out the temp repair for a permanent solution.

The 1980's vintage fuel line was replaced years ago, and again this spring .

Boat in a Pioneer 10, built in the UK

Give a shout if your up in the salish sea next summer.
 

jssailem

SBO Weather and Forecasting Forum Jim & John
Oct 22, 2014
23,170
CAL 35 Cruiser #21 moored EVERETT WA
Try Seattle Fluid Systems. (425) 825-1115

When I was looking for a fuel line connector for my Perkins the Kent engine facility manager suggested them as a fitting resource. They put the parts together and made the fuel filter install a breeze.