I have a John Bean model IV tire machine. These were sold by snap on. I bought mine off craigslist a few years ago. The break down arm isn't working right. It doesn't have anywhere close to the pressure it used to. I had the cylinder rebuilt with snap on parts. That helped some but it's still not great. I think the valves in the pedals need serviced and/or replace. Here is the catch. It doesn't have a serial number on it. Without this snap on won't talk to me for any amount of money. Does anyone know places that work on these things or sell parts?