PISTON 5204603 - Caterpillar

Replace Thermostat, Gaskets and Seal
Refer to the Service Manual for detailed instructions regarding Disassembly and Assembly of the Cooling System. Repeat procedure for both thermostat housing assemblies.Replacing the thermostats prior to failure is a recommended preventive maintenance practice because it reduces the chances for cooling system problems and unscheduled downtime.
Failure to replace your thermostats on a regularly scheduled basis could cause severe engine damage.
If replacing thermostats ONLY, drain the coolant from the cooling system to a level below the thermostat housing.5. Disconnect hose assemblies from radiator and each thermostat housing assembly.6. Remove bolts and thermostat housing assembly.7. Remove the gasket, thermostat and seal from each housing.
Former thermostats may be used, if they meet test specifications as described in the Service Manual (and are not damaged or have excessive buildup of deposits).
The thermostats can be reused if they are tested and meet the test specifications in the Service Manual.Flush
8. Refill the cooling system with clean water mixed with the proper concentration (six to ten percent) of Fast Acting-Type Caterpillar Cooling System Cleaner (4C4611). Tighten cooling system vent cap. For proper cooling system maintenance cleaning, refer to label directions for the type of Caterpillar Cooling System Cleaner used in your cooling system.9. Start and run (operate) the engine to circulate fluid in the cooling system.10. Stop the engine and allow to cool. Loosen cooling system vent cap and drain plugs.11. Drain the cleaning solution. Flush the cooling system with clean water and a neutralizing solution until draining water is clear. Clean and install all drain plugs and/or close the drain valve. Sodium Carbonate crystals at a rate of 250 grams per 40 liters of water (1/2 pound per 10 U.S. gallon of water) may be used as a neutralizer. Repeat Steps 8 thru 11 if necessary until the draining water is clear.Install Thermostat
Caterpillar engines incorporate a shunt design cooling system and require operating the engine with a thermostat installed.If the thermostat is installed wrong, it will cause the engine to overheat.
Inspect gaskets before assembly and replace if worn or damaged.12. Install a new seal in each thermostat housing and install new thermostats.13. Install a new gasket and the thermostat housing on the engine cylinder head.14. Install the cooling system connections and tighten the hose or piping clamps.Fill
All water is corrosive at engine operating temperature. The cooling system should be protected with cooling system conditioner at all times. Use Caterpillar liquid cooling system conditioner to treat the coolant mixture.
Refer to the Cooling System Specifications section of this publication for all information regarding about the appropriate maintenance of the cooling system or contact your Caterpillar dealer for assistance. See Refill Capacities chart in this publication for the capacity of your engine's system.15. Be certain all drain plugs are clean and installed. Premix a solution of acceptable water and Caterpillar Antifreeze.16. Start and run the engine with the cooling system vent cap loosened. Operate the engine and allow the coolant to warm, the thermostats to open and the coolant level to stabilize. Inspect