I have a strange problem with a tyre on my 97 GC. It is a 16" rim and should be inflated to 33psi, but when it is pumped to 25psi it stops inflating.
I have changed the valve core and checked it with a dial and a digital guauge and they both read 25psi

sounds more like a problem with compressor than the tire

what is the output pressure on the compressor regulator?

The max pressure is 95psi, it inflates the other tyres okay.

Kind of bizzare....I'll be curious if/when you figure this gremlin out.

Try deflating it all the way then refilling it?

How low was it when you started filling it up? Is the bead of the tire seated on the lip of the wheel?

Is it leaking out or just not inflating anymore? If it won't inflate over 25psi it's not a tire problem unless its leaking somewhere.

maybe a faulty shrader valve you can buy it and replace them pretty easily you will need to buy the shrader valve tool if u dont have one.

I discovered it was dirt inside the valve body. Replacing the inside core failed to fix it so I removed the core and stuck a wooden scewer into the valve and it came out covered in mud.
I can inflate the tyre but only very slowly so there must still be dirt in the tyre

That is why people have to remember to ALWAYS replace their valve caps on the valve stems(not saying you didn't) because all kinds of funny crap can get in there.

Wouldn't replacing the valve stem solve this problem?

Yeah, people overlook how simplistic and important that plastic cap is.

And yeah, a whole new valve stem would correct it. Take the tire off, and down to any local garage. I replace valve stems for free on loose wheels, just cause the part cost me all of $0.03 and it takes 40 seconds to replace.

This is Scotland though, no one does anything for free

The tyre is inflated to 33PSI so it seems to be sorted out now.

This is a new one I never heard of.

Glad you got the problem solved.