The Ford Barn

Lawson Cox · 10-28-2022, 02:14 PM

I guess the title says it all. Eyes are dim, hands are shaky so thread gauge sort of useless now a days. So, what is the thread size? Thanks.

Mart · 10-28-2022, 03:53 PM

1/4 npt*

*Well it is on the 85 horse motors.

Lawson Cox · 10-28-2022, 08:00 PM

Quote:

Originally Posted by Mart

1/4 npt*

*Well it is on the 85 horse motors.

Thanks Mart. I never have been able to get the pipe thread thingie straight in my mind without a lot of head scratching. Everything pipe goes by ID and not OD. Its corn fusing.

Bored&Stroked · 10-29-2022, 08:56 AM

Quote:

Originally Posted by Lawson Cox

Thanks Mart. I never have been able to get the pipe thread thingie straight in my mind without a lot of head scratching. Everything pipe goes by ID and not OD. Its corn fusing.

The easiest mental way to initially think about it is that the NPT pipe size (based on ID) is usually about 1/2 the size of the threaded hole it is going into.

It is not exact but gets your mind in the right place!

glennpm · 10-29-2022, 09:38 AM

I like B&Ss quick check, "The easiest mental way to initially think about it is that the NPT pipe size (based on ID) is usually about 1/2 the size of the threaded hole it is going into."

T Scott · 10-29-2022, 10:50 PM

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Quote:

Originally Posted by Mart

1/4 npt*

*Well it is on the 85 horse motors.

Checked my V8-60, 1/4 NPT also.

aussie merc · 10-29-2022, 11:29 PM

if ones 1/4NPT they all will be most likely as cant see henry buying 2 things to do the same job [the more you buy the harder you can tighten the screws]

Lawson Cox · 10-30-2022, 01:03 PM

Thanks again fellers. I'll check my taps and dies. I should have 1/4" npt but it's been so long since I had need for one I may have to head out fo da sto.

10-28-2022, 02:14 PM	#1
Lawson Cox Senior Member Join Date: May 2010 Location: Above the gnat line in Georgia Posts: 7,009	Thread size for engine block petcock I guess the title says it all. Eyes are dim, hands are shaky so thread gauge sort of useless now a days. So, what is the thread size? Thanks. __________________ Life is like a roll of toilet paper. The closer to the end, the faster it goes. It is better to be seen, than viewed. "We sleep safe in our beds because rough men stand ready in the night to visit violence on those who would do us harm". Last edited by Lawson Cox; 10-28-2022 at 03:26 PM.

10-28-2022, 03:53 PM	#2
Mart Senior Member Join Date: May 2010 Location: Solihull, England. Posts: 8,755	Re: Thread size for engine block petcock 1/4 npt* *Well it is on the 85 horse motors.

10-29-2022, 11:29 PM	#7
aussie merc Senior Member Join Date: Sep 2016 Location: sydney australia Posts: 1,034	Re: Thread size for engine block petcock if ones 1/4NPT they all will be most likely as cant see henry buying 2 things to do the same job [the more you buy the harder you can tighten the screws]

10-30-2022, 01:03 PM	#8
Lawson Cox Senior Member Join Date: May 2010 Location: Above the gnat line in Georgia Posts: 7,009	Re: Thread size for engine block petcock Thanks again fellers. I'll check my taps and dies. I should have 1/4" npt but it's been so long since I had need for one I may have to head out fo da sto. __________________ Life is like a roll of toilet paper. The closer to the end, the faster it goes. It is better to be seen, than viewed. "We sleep safe in our beds because rough men stand ready in the night to visit violence on those who would do us harm".