I have a John Deere 3038E with the rear of lawn filled with calcium and I have not been able to check the pressure with a standard automatic manometer (non-electronic). When I put the pressure gauge, I did not read any pressure. Could the valve be covered with calcium? They have always been the plugs of valves set so there is no external dirt. Check with the stems at the top. I am doing something wrong? Should I remove calcium for corrosion reasons?
I think you can have only a very low air pressure.
You need to get a tire meter that is intended for tires filled with liquid, standard meters will not work. Your distributor must have one.
Yes, it will drip and drip a little when checking the pressure and the meter will be cleaned by itself when it removes it, that is, the plunger returns to zero under the spring pressure, expelling the liquid.
I check the pressure at the top, but it is more usual, because if the tires are well full, the rim will always be below the level of liquid.
Yes, the CACL can cover the core of the valve and even the water stem on the tires filled. I had a punctured tire several years ago, it was fine one day, punctured 3 days later. I removed the valve cap, hit the valve stem with 165 psi of air and nothing to do.
I finally had to remove the core from the valve and drill the obstruction with my wireless drill, then aerate the tire. He stayed up to a week or two, then flat again. Anyway, I wanted to remove the CACL, it had been on the tractor tires for at least 46 years, the tires were very rusty.
When I pulled the air chamber, and the old patch was dripping, the patch was not installed by me, so at least 46 years old. I have cleaned with sand jet the two tires, I have printed and painted and installed new air chambers on the two rear tires.