A tractor tire question

I had a Schrader valve go bad in a tractor rear. When I tried to pull the core the wings broke off the top of the valve. "No big deal" I think, "I'll just put in a new body." This is the 2 piece type that allows for loading the tire and uses the TRCH-3 type insert. The valve body didn't want to come out. I assume that was because of corrosion from the tire being laded with calcium chloride. I finally got it out by gripping the outside of the inner tube part with Vice-Grips and using a small set of Channel Locks on the valve body. The threads were pretty mangled looking on the old valve body and I wanted to run a tap in there to clean the female threads up on the tube side of the assembly. I checked the new valve body threads against everything I could find. Even a Starrett thread checker was no help. Grainger had a blurb stating the thread on their valve bodies was .305-32 but my mic says the major thread diameter is almost .375 and the minor diameter didn't look like it was that much smaller. I also found reference to the cap end of the valve being .305-32, so I'm still unsure what thread it is. I finally drove to town, checked with my local auto parts store and they were no help. Went tot he long time Goodyear farm tire dealer and the old gent there said he'd looked into the same thing many, many years back and never found an answer to the question. So on his advice I lubed everything up and, using Vice Grips and a small set of Channel Locks, got it back together. This was not my preferred solution to the problem at all!

Would anyone have an answer to the thread of the 2 piece tractor valve type set up? It doesn't look like a pipe thread and it's a very fine thread in the 28-40 TPI range I'd guess. I thought for sure there'd be a tool like the 4 way valve service tools Milton sells, but no such creature seems to exist!

If you have ever seen a 4way valve core tool you have seen what it
takes to rethread your stem, They are made in different sizes

Bret The thread figure I got when I looked into it was a pitch of 9V1 .375x32 tap tube was a 12V1.482x26 Mcmaster-carr was Part number 26005A213 $47.63 for that. And a 9V1 2521A447 $8.23 this was for the pipe molded into the tube for a rear tractor tire with the air water stem. The 482x26 was for the outside and the 375x32 was for the inside thread.
I hope this helps with your problem.

504 I think he is looking for the tap to thread the stem into the pipe on the air water stems for rear tractor tires. Not the valve core.

As 504 told you. Ebay has all of this stuff. I must have four of them laying
around.

Right track, OP needs to look for one of these for ?large bore? valve stems. Large bore valves are used on earth moving equipment, but it?s the same size as the big side of an Ag air/liquid valve.

Ok. but that is the size on everything I have. Oh well. That is also why all of my garden and lawn tractors have loaded tires with windshield wiper fluid instead of that highly corrosive stuff. Incredible how much difference it makes on lawn mower type machines. Machine is sooo much more stable. Far less tippy and much better traction.

(quoted from post at 17:36:54 01/03/20) As 504 told you. Ebay has all of this stuff. I must have four of them laying
around.
<img src="https://www.yesterdaystractors.com/cvphotos/cvphoto1170.jpg">

Click to expand...

That's for a passenger car/lite truck type tire. I also have several. I'm looking for one for this type core- https://www.miltonindustries.com/tire-hardware/tire-valves/tr-ch3-valve-core-housing.html

(quoted from post at 17:13:23 01/03/20) Bret The thread figure I got when I looked into it was a pitch of 9V1 .375x32 tap tube was a 12V1.482x26 Mcmaster-carr was Part number 26005A213 $47.63 for that. And a 9V1 2521A447 $8.23 this was for the pipe molded into the tube for a rear tractor tire with the air water stem. The 482x26 was for the outside and the 375x32 was for the inside thread.
I hope this helps with your problem.

Click to expand...

3/8-32 tap, I think that's what I want. Thank you, I'll see what I can find.

(quoted from post at 16:58:29 01/03/20) If you have ever seen a 4way valve core tool you have seen what it
takes to rethread your stem, They are made in different sizes

Click to expand...

If you ever run across one for the tractor rear tube using the fluid fill type valves, please let me know. I'd buy one for sure.