Fuel Pick-up

Tahorover

Chief Petty Officer
Joined
Mar 7, 2011
Messages
572
Re: Fuel Pick-up

1/4" NPT better known as national pipe thread
 

detrlions10

Cadet
Joined
May 18, 2011
Messages
24
Re: Fuel Pick-up

Thats what I thought, but that seems to be the size of the threads going into the valve. I bought a 1/4 NPT, and threaded it through, but it seems too small. The nylon tubing is too large to even fit down the tank, I had to turn it to thread it in. Has anyone here ever put one of these in? Was it difficult to get the nylon tube down into the tank?
 

soggy_feet

Senior Chief Petty Officer
Joined
Oct 10, 2009
Messages
713
Re: Fuel Pick-up

You're not making much sense to me...
You bought a 1/4NPT fitting, and a 1/4NPT tap... but your tapped hole is too small for the nylon tubing attached to your 1/4npt fitting?

Are you tapping a new hole, or 'chasing' the threads of the original hole? How thick is the material you're tapping into on the tank?

If this is a new hole, you should be using a 7/16ths drill. Test fit the fitting as you're tapping. Make sure it screws in more than just a couple turns. Youve got a bunch of threads on the fitting, might as well use them.
 

detrlions10

Cadet
Joined
May 18, 2011
Messages
24
Re: Fuel Pick-up

You're not making much sense to me...
You bought a 1/4NPT fitting, and a 1/4NPT tap... but your tapped hole is too small for the nylon tubing attached to your 1/4npt fitting?

Are you tapping a new hole, or 'chasing' the threads of the original hole? How thick is the material you're tapping into on the tank?

If this is a new hole, you should be using a 7/16ths drill. Test fit the fitting as you're tapping. Make sure it screws in more than just a couple turns. Youve got a bunch of threads on the fitting, might as well use them.

Yes, I am "chasing" the threads of the original hole. The last fitting that was in there got broken off flush with the tank. I had to use an easy out to get it out. Because it is aluminum, some of the previous threads were "smashed" into the old ones when using the easy out. I agree, something does not seem right here.

The tap that I bought came with the 7/16th drill. It goes through with no issues. That make that tube pretty thick if you look at the link. Maybe I should just force it in??
 

detrlions10

Cadet
Joined
May 18, 2011
Messages
24
Re: Fuel Pick-up

Here are some picks of the hole after I have tapped it. You call see that the original threads are wider that what was tapped...
 

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detrlions10

Cadet
Joined
May 18, 2011
Messages
24
Re: Fuel Pick-up

Any suggestions on the tap size? It has to be larger than the 1/4 NPT. I really want to get this done today. I tried called the tank manufacturer, but they are out of business.
 

Don S

Honorary Moderator Emeritus
Joined
Aug 31, 2004
Messages
62,321
Re: Fuel Pick-up

Depends on what you have, 3/8" or 1/2" NPT is the most common sizes of pickups. Measure your threads.
 

detrlions10

Cadet
Joined
May 18, 2011
Messages
24
Re: Fuel Pick-up

Should I measure staright across with a tape measure? Thanks for the response.
 

soggy_feet

Senior Chief Petty Officer
Joined
Oct 10, 2009
Messages
713
Re: Fuel Pick-up

Excellent.

its hard to measure NPT, 1/4 isn't really 1/4 in any way, and its tapered, so the bottom of your hole is smaller than the top anyway. Fortunately, like you found, there aren't that many options that it could be.

Hope you're on the water soon now!
 
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