Ok, started to install the Autometer snubber, 3279, today on my fuelpressure guage to stop the needle bouncing. Just to clarify, the threads are 1/8" male by 1/8" female on the snubber, right? The guage sending unit and the snubber threads into the fuel line without any issue. I attempted to thread the sending unit into the snubber outside the truck just for ease of install and it only went about one thread and stopped like the thread pitches were different. I didn't use wrenches on the pieces because I didn't want to screw anything. The female threads look great. Is it just me, or maybe a tapered female thread? Anyone else have this problem?

 

the 3279 is defiantly 1/8" npt, every gauge i have seen is npt. you may have to run a bottoming tap in to finish the threads. try to screw a nipple in it and see what happens

 

I'm gonna give that a whirl...thanks.

 

Yep, mine was just like that. After determining that the threads do match and the pitch was the same I just went ahead with it. That was a year ago and it's fine. If I remember right one was NPT and the other just pipe which didn't make sense as I never knew any different. Bottom line is the guru at the International/Case dealership I've known since I was a kid told me to screw them together tight and don't look back. I did and all is well.

 

Grabbed a tubing fitting today and it went in a little further by hand. I'll try and "loosen" the threads up a bit before I go and crank on the sending unit...

 

FYI, NPT is pipe.

 

NPT means it is a tapered thread so it gets tighter the farther in it goes.

 

Bingo. The thread pitch is the same one is just tapered. I learned something new that day.

 

That is correct. But what everyone commonly refers to as "pipe thread," is NPT. aka national pipe thread