I have a Linde 40HD, serial number H2X394TO3995. It seems to building pressure in the cooling system. It has cracked one plastic reservoir already, and broken two of the plastic fittings in the hose. We took the thermostat out to see if maybe it was bad, but didn't seem to make a difference. Lift started running hot before it started busting fittings, that's when we took out thermostat. Water seems to be circulating, but could it be a weak water pump?