Can't remove valve stem cores

[JazzDad]

So, there are lots of posts about leaking valve stems. I have a stem that I can't get air in or out. The core depresses, but I can't move any air past it. I suspect the ballast in the tire has clogged (maybe corroded) the core. I also can't unscrew the core. I've tried soaking the inside of the stems with PB Blaster. I sure would hate to have to take the wheels off and replace the tubes. Any thoughts on how to remove these cores?

 

[Coyote machine]

What are you using to try to unscrew the valve stem? Have you tried removing it when it's at the top of the wheel rotation with less pressure from the liquid in the tire?

 

[SPYDERLK]

So, there are lots of posts about leaking valve stems. I have a stem that I can't get air in or out. The core depresses, but I can't move any air past it. I suspect the ballast in the tire has clogged (maybe corroded) the core. I also can't unscrew the core. I've tried soaking the inside of the stems with PB Blaster. I sure would hate to have to take the wheels off and replace the tubes. Any thoughts on how to remove these cores?

Fluid valve stems are usually 2 part. With them the core is in an outward part that screws into the part that is vulcanized onto the tube. Pls confirm that you have the regular automotive type valve stems and not the 2 part liquid stems.

 

[JazzDad]

Yes, I have the tire at the 12 o'clock position. Remember, I can't get air in or out.

Yes, common-type stems, that are a part of the tube. The tractor was previously owned by a couple of knuckle-brained brothers, so who knows what they may have done.

I am trying to get the core out to ream something in there to break whatever is clogging the stem behind the core. The front tires are fine.

 

[SPYDERLK]

Yes, I have the tire at the 12 o'clock position. Remember, I can't get air in or out.

Yes, common-type stems, that are a part of the tube. The tractor was previously owned by a couple of knuckle-brained brothers, so who knows what they may have done.

I am trying to get the core out to ream something in there to break whatever is clogging the stem behind the core. The front tires are fine.

OK. I think you should drill it out, but 1st a question. When you failed to remove it did you turn hard enough to break off the tab portion that the tool keys onto?

If not - before you do, first get a metal cap and cut off its top. Then screw it onto the stem until its threads are over the portion where the threads on the valve core engage. Now squeeze the cap with vise grips [an old pair with tips worn smooth would be best] to distort the stem slightly around the core. The aim is small distortion to disturb the internal corrosion on the core threads. Set grip pressure prudently and repeat grip several times at different points. You might try removal torque during and after and while gently applying different squeezes - oil up the grips so they work smoothly. If it moves youre home free.

Good luck​

 

[Steave]

I've had some luck with one of these if the inside of the stem tabs break off.
The tapered end is backward threads and will sometimes grab the stem but if its stuck with some kind of flat fixer upper it may never come out.
The straight threaded side is for re-tapping the threads if you ever get the old one out.
It also has a re-tapping part for the outside of the stem where the cap goes.

SLIME 4-way Valve Tool - 33M173'|'288 - Grainger

 

[JazzDad]

I have not put the full mojo on it, so have not broken anything off inside the stem. I'll try what you suggested, Spyder - that makes good sense. If it doesn't work, the screw extractor will be tried. I have a set in various sizes.

Thank you much, all!

 

[JazzDad]

I sprayed PB Blaster into the stems and let them soak for about a week. The cores came out. However, no air did. I found a small screwdriver that would fit within a stem (tested on a stem not installed in a tire, so as to not damage those internal threads). Inserted it, but it didn't budge beyond about 3/4 inch. Got out the drill motor and chucked up a 3/32" bit. Ran it in there, and a blob of what looked like cement came out followed by a stream of water. (I had the stem positioned at 9 o'clock for easy access.) Threaded the core back in and was able to properly inflate the tires with no subsequent leak.

Next project: Replace the gearbox on the mowing deck. Anyone have a suggestion on how to safely put it on its side, and keep it from tipping while taking large wrenches to the various fasteners?

 

[kthompson]

If you have any kind of loader or hoist I would lift the mower at least to the point of having the chain or straps tight to prevent the deck from having slack so it could fall. Also would suggest use of impact wrench over hand wrench as you will not put near the load on the deck causing it to tip.

 

[SPYDERLK]

I sprayed PB Blaster into the stems and let them soak for about a week. The cores came out. However, no air did. I found a small screwdriver that would fit within a stem (tested on a stem not installed in a tire, so as to not damage those internal threads). Inserted it, but it didn't budge beyond about 3/4 inch. Got out the drill motor and chucked up a 3/32" bit. Ran it in there, and a blob of what looked like cement came out followed by a stream of water. (I had the stem positioned at 9 o'clock for easy access.) Threaded the core back in and was able to properly inflate the tires with no subsequent leak.

Next project: Replace the gearbox on the mowing deck. Anyone have a suggestion on how to safely put it on its side, and keep it from tipping while taking large wrenches to the various fasteners?

If you have any kind of loader or hoist I would lift the mower at least to the point of having the chain or straps tight to prevent the deck from having slack so it could fall. Also would suggest use of impact wrench over hand wrench as you will not put near the load on the deck causing it to tip.

Great news!​

Next - If you dont have a loader and the mower is 3point, you can remove the center link and hoist the back of the mower from the ROPS to pivot it way up for access and inherent stability.