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03-22-2021, 07:08 PM | #1 |
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'30 under tank gas valve threads
Need the thread size for the in-tank hole and the fuel line connection end.
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03-22-2021, 07:24 PM | #2 |
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Re: '30 under tank gas valve threads
The tank threads are ¼" pipe thread. Sorry I don't remember what the fuel line is off the top of my head.
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03-22-2021, 09:08 PM | #3 | |
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Re: '30 under tank gas valve threads
Quote:
Further to YB, technical names for the input side thread is 1/4"-18 MPT (male pipe thread) or 1/4"-18 NPT-M (National Pipe Thread - male) for the fitting, and 1/4"-18 FPT or 1/4"-NPT-F for the tank. If you are going to use a tap to clean up the threads in the tank be careful you don't overdo it, with a tapered thread the farther you go in the bigger the hole, and you may inadvertently make it too large for the valve to properly seat. DAHIK. Don't forget to put a screen into the gas valve before reinserting it. JayJay
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03-22-2021, 11:27 PM | #4 |
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Re: '30 under tank gas valve threads
Haha, Have you ever seen a ¼" pipe thread that wasn't ¼-18 NPT? I don't need no stinky technical names...
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03-23-2021, 09:27 AM | #5 | |
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Re: '30 under tank gas valve threads
Quote:
JayJay
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03-23-2021, 09:59 AM | #6 |
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Re: '30 under tank gas valve threads
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03-23-2021, 10:19 PM | #7 |
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Re: '30 under tank gas valve threads
Thanks Jay Jay. So the thread into the tank is 14-18NPTFine and the output to the gas line is 1/4-18MPT, male compression end ? Knew they were different but couldn't recall without a valve or gas line on hand.
Last edited by duke36; 03-23-2021 at 11:12 PM. |
03-24-2021, 05:35 AM | #8 |
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Re: '30 under tank gas valve threads
Its 5/8" - 18
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03-24-2021, 06:21 AM | #9 |
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Re: '30 under tank gas valve threads
" Haha, Have you ever seen a ¼" pipe thread that wasn't ¼-18 NPT? ....Y-Blockhead"
Oh yes, in the wide world beyond the shores of the USA. |
03-24-2021, 06:28 AM | #10 |
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Re: '30 under tank gas valve threads
I think you need to back up a little bit.The tank thread size is 1/4 pipe.It is not fine.The outlet to the gas line is not pipe or compression,it is flare.
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03-24-2021, 08:45 AM | #11 | |
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Re: '30 under tank gas valve threads
Quote:
This is kinda getting way skewed. The output is ⅝-18 U.S.F thread, so it is not anything special -however where the issue can be found is modern fittings are not always manufactured to the same thread diameter as Ford engineers specified. Below is a PDF that shows a portion of the A-9190 print that gives exact specification of the threads. As shown in the print, Ford used special gages to verify fit for many pieces such as this in their QC process. . |
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03-24-2021, 10:43 AM | #12 |
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Re: '30 under tank gas valve threads
Ok I can make out 5/8-18 US fine. So I found this valve cut from the vendor's catalogue and have placed dimensions in order to chase the tank threads.
Last edited by duke36; 03-24-2021 at 11:01 AM. |
03-24-2021, 12:03 PM | #13 | |
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Re: '30 under tank gas valve threads
Quote:
1/4"-18 NPTF gas tank fitting, that's 1/4"-18 National Pipe Thread FEMALE, not fine. The NPT standard defines the taper and the pitch, and the F defines that it's a female (internal thread). The corresponding fitting on the valve is 1/4"-18 NPTM, with the "M" standing for "male" (external thread). Output to the gas line is (as noted above) 5/8"-18. But as I stated above, it's a flare fitting. I believe that a 5/8"-18 UNF (Unified National Fine, which is 5/8"-18) die should chase the threads if that's what you're after. And we don't even want to start a conversation about thread shapes... JayJay
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03-24-2021, 12:19 PM | #14 |
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Re: '30 under tank gas valve threads
I don't want to sound like we are ganging up on you as that is definitely not my intent, but look at the print above and I think you will see that it really is not smart to "chase" the tank threads unless you have the proper tap ...which Ford used a different thread pitch than what I think you will find in taps today. I have experienced many gas tanks that had the threads cut oversized due to an incorrect tap size.
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03-24-2021, 04:58 PM | #15 | |
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Re: '30 under tank gas valve threads
Quote:
BTW, same caution on "chasing" the GAV housing thread in a Zenith, that's a 1/8"-27 NPTF. JayJay
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03-30-2021, 09:46 AM | #16 |
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Re: '30 under tank gas valve threads
Inside steel fuel lines all 5/16" OD ?
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04-01-2021, 06:22 PM | #17 |
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Re: '30 under tank gas valve threads
Just found the parts in a box. The early valve is like the engin dwg. The later ones the handle nut has internal threads which I'm not sure what the threads are.
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