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WTB - M38A1 Fuel Shut-Off Valve
Posted: Mon Jun 19, 2017 3:23 pm
by w30bob
Hi Guys,
Anybody know where I can find one of those little brass shut-off valves that sits next to the radiator and frame so I can complete my fuel system install? The usual suspects don't list one online, so I'm asking before I start calling.
thanks,
bob
Posted: Mon Jun 19, 2017 8:16 pm
by RonD2
Hi Bob,
This is what I used. Made in South Carolina U.S.A. (company dates back to 1931). It's great quality at a reasonable price. And if it's not original, it's sure pretty close.
I didn't want to take a chance with fuel and a NOS or take-off valve, which are hard to find and kind of pricey either way:
http://www.andersonbrass.com/MARINE_FUEL.PHP
Posted: Mon Jun 19, 2017 10:36 pm
by wesk
Bob, I googled the PN and here's the results:
http://www.surplusjeep.com/M38A1/m38a1-group_3_fuel.htm
M 7346871 Valve, plug, shutoff, 1/2-20NF internal thread (fuel line) $32.95
Posted: Tue Jun 20, 2017 6:45 am
by w30bob
Thanks guys. Will check into both of them. Wes, I was aware of surplusjeep listing it, but my past dealings with them were let's just say significantly less than satisfactory. But maybe they've improved since then. Will get something ordered today.
regards,
bob
Posted: Tue Jun 20, 2017 8:16 am
by wilfreeman
Hey Ron,
That (the M670) looks like the one that is on my (very original) 1964 USMC M38a1. The handle is slightly different, but the valve looks the same. Dorchester County, huh? I am about 40 miles north of Columbia - in Chester Co.
Posted: Tue Jun 20, 2017 2:37 pm
by RonD2
That's about 150 miles from Summerville straight shot up I-26 to I-77......I'll look you up sometime!
I see on your blog you mentioned Wigington Surplus in Piedmont SC. Does he have any M38 stuff worth the trip?
Posted: Tue Jun 20, 2017 5:10 pm
by wilfreeman
Most of the Jeep stuff he has left is m151 although I've found some a1 (electrical mainly) stuff mixed in. He has a LOT of stuff! Be prepared to spend hours and hours rummaging over, under and through stuff - it is not organized. You might get lucky and find what you're looking for. Mostly good prices too.
Posted: Tue Jun 20, 2017 7:01 pm
by w30bob
Ron,
Can you help me out a bit here? From the ORD the fuel lines this shut-off valve connects between are listed as as inverted flare 5/16 tube. That size line uses a male flare nut with 1/2-20NF threads. So the shut-off valve needs to have both ends accept a male nut. I don't see any of the valves listed with 2 female flare ends threaded in 1/2-20NF. So which one did you buy?
Thanks,
Bob
Posted: Tue Jun 20, 2017 10:13 pm
by wesk
Just buy this one and use two pipe to inverted flare adapters.

\
M672C
Left Port________Right Port___Material____ Part Number___UL Approved
1/4" F NPTF_____1/4" F NPTF__Brass________M672C-L _________Yes
and two of these weatherhead inverted flare tube to pipe adapters:
Tube__Male Pipe__Catalog
O.D.___Thread___Number_____C________D____L
5/16_____1/4____202x5x4___19/32____.220__0.98
C = Hex size
D = bore
L = length

Posted: Thu Jun 22, 2017 7:35 am
by RonD2
Hi Bob,
I have a M38 so my fuel lines are 1/4-inch instead of 5/16-inch (except for the one line from the pump to the carb is 5/16-inch). I did buy the M672C as Wes pointed out, and also had to use a pair of inverted flare adapters.
Posted: Sun Jun 25, 2017 10:02 am
by w30bob
Hi Ron,
Yup........I hear ya. I'm doing it the same way. The only thing that sucks is the adapters only thread in a few threads on each side of the valve, so the valve with 2 adapters is almost twice as long as just the correct valve would be. Not a big deal, but looks a little bit jury rigged when done. These valves are sold mainly for marine (boat) fuel systems. I'm surprised that fuel lines in boats aren't inverted flare.
I called around and no one has the correct valve. All the brass fitting manufacturers have a minimum order of something like 1000 pieces before they'll make the correct valve. At some point in time I assume all the MV parts vendors will put their heads together and place an order. Until then it's either what we're doing or getting lucky and finding a decent used one.
Let me say thanks again to you and Wes for all your help.
regards,
bob
Posted: Sun Jun 25, 2017 10:20 am
by wesk
The only thing that sucks is the adapters only thread in a few threads on each side of the valve
Is the limiting factor the depth of the threads in the ends of the valve or the diameter of the threads on the adapters? If the only issue is the male pipe threads are too large on the adapters you can either chop a short bit off and re-thread with a pipe die or you can try re-cutting the original adapter male threads with several different brand pipe dies as long as the valve's female threads allow the deeper travel of the skinnier male pipe threads.
Posted: Mon Jun 26, 2017 8:05 am
by w30bob
Hi Wes,
Yes, I was thinking the same thing. My issue is the threads get tight too fast.........so cutting some off and re-cutting the threads will fix it. But I don't think we have pipe threading dies that small at work. I'll find out today. Right now the adapters only thread in about 3 threads and grind to a halt. No obstructions, just the taper doing its thing a bit early.
thanks,
bob
Posted: Mon Jun 26, 2017 8:39 am
by wesk
Before I cut any meat off I would get a couple of different manufacturer's dies and taps and try re-cutting the existing threads to either reduce the run-on diameter slightly of the adapter's male thread or increase the diameter slightly of the valve's female threads. If you can find some overseas produced taps & dies they are often not in spec size wise!
An alternative is to get an abrasive paste on the threads and screw them together a dozen times renewing the abrasive paste each time. Then clean all threads and check fit.
Posted: Wed Jun 28, 2017 6:31 am
by w30bob
Hi Wes,
Checked the dies we had at work and I see the problem now. I can cut material off the adapter, but when the threads were cut initially the die ran all the way to the portion of the adapter that a wrench goes on. So cutting it shorter and re-threading won't change the diameter of the threads remaining because the die won't be able to travel any further down the fitting to cut the taper closer to the area where the wrench goes on. There's just not enough meat on the adapter to move the taper back.
I decided to just put it together and live with it for now. I have to make the small hard line that's right after the valve (that connects to the rubber hose.......so I can just make that pipe a little shorter to compensate.
thanks,
bob