Cooling System Troubleshooting Chart

* If the engine tends to overheat, removal of the thermostat will adversely affect cooling efficiency.

* IMPORTANT: The thermostat's rubber seat on the main poppet valve will deteriorate if it is contacted by oil. If the rubber seat is found soft, or cracked:
^ Determine the cause for oil in the cooling system.
^ Flush the cooling system as following the instructions.
^ Replace the thermostat cartridge.
^ Fill the cooling system with a 50/50 solution of DEX-COOL (R) antifreeze and clean water.