M923A2 FRONT TIRES NOT TAKING AIR...OR HAVE ANY AIR PRESSURE

[FIREFIGHTER]

So we've had this truck as our forestry tanker since 2013?? The CTIS has never worked and we've never tried to fix it. The other day, they tried taking a tire pressure reading.......nothing. Both front tires didn't read/ have any air pressure. Tires are full of air. I tried putting air into the tires.....nope. I pulled the valve core out of the shraeder valve....nothing. Couldn't see any kind of check valve or obstruction. This is how we've been checking the tire pressure and filling it for years..no problems until now.
Is there so sort of check valve in there that could get corroded up and stop the air from getting in/ out?? I'm kind of baffled...but this is the perfect time for this to happen.....2+ FT of snow on the ground...so no wildfire danger!!
Any help would be appreciated......Thank you.
(PS I've spent a couple of hours searching posts on here. I haven't found any ....yet.)

 

[ericp351]

12 years on same tire? Any way, look into for fill valve 2 of 2. Sounds like a clog outboard. Inbd is tight for clearance, but usable. Goes to same spot on rim as fitting you show.

 

[FIREFIGHTER]

12 years on same tire? Any way, look into for fill valve 2 of 2. Sounds like a clog outboard. Inbd is tight for clearance, but usable. Goes to same spot on rim as fitting you show.

Yes......12 years on same tire. Truck doesn't get used much (Thankfully)......wildland fires are not fun.
But what I don't understand is why BOTH front tires now don't have air pressure readings nor can you put air into them.

I think what I am going to do is order some O rings and take the tires apart. Maybe its rusted closed??

What is fill valve 2 of 2?? I don't understand that reference.

Thank you for your reply.

 

[ericp351]

My a2 has 2 fill schraders, each front. Look inboard. No Ctis stuff between inbd and center openings into rims. GEMPLERs sells O rings, no relations to me.

 

[Jbulach]

There are most likely valve cores installed in the wheels, outboard valve stems, behind the ctis wheel cylinder hose. This will not allow the CTIS to function or air pressure to flow back to the wheel valve. As ericp351 said, check and fill air pressure from the inside valve stem.