19300-ZV5-043 Honda SEE PART DETAILS - PRI; THERMOSTAT ASSY. (Honda Code 5592167). (72 DEGREES C)

Hints for Cold Weather Operation
If the engine is started, operate the engine until a minimum operating temperature of 71 °C (160 °F) is achieved. Achieving operating temperature will help prevent the intake valves and exhaust valves from sticking.
The cooling system and the lubrication system for the engine do not lose heat immediately upon shutdown. This means that an engine can be shut down for a few hours and the engine will start readily. If the engine is shut down for at least 8hours, the engine should be considered cooled to outside temperature.
Install the correct lubricant in each compartment before the beginning of cold weather.
Check all rubber parts (hoses, fan drive belts, and so on) weekly.
Check all electrical wiring and connections for any fraying or damaged insulation.
Keep all batteries fully charged and warm.
Fill the fuel tank at the end of each shift.
Check the air cleaners and the air intake daily. Check the air intake more often when you operate in snow.
Personal injury or property damage can result from alcohol or starting fluids.Alcohol or starting fluids are highly flammable and toxic and if improperly stored could result in injury or property damage.
DO NOT USE ETHER (starting fluids) unless specifically instructed to do so. If the engine is equipped with an Air Inlet Heater (electrically or fuel ignited manifold heater), DO NOT use ether (starting fluids) at any time. The use could result in engine damage and/or personal injury.
The optional automatic ether injection system is the only starting fluid system that is recommended. Excessive starting fluid can cause piston and ring damage. Use starting fluid for cold starting purposes only.
Inject starting fluid only when the engine is cranking.
Dryers for the air system may be effective in reducing moisture condensation and the formation of ice in air systems.
The injection of alcohol may prevent moisture from freezing the air compressor governor and other components of the air system.
For jump starting with cables in cold weather, refer to the Operation and Maintenance Manual for jump starting instructions.Viscosity of the Engine Lubrication Oil
Proper engine oil viscosity is essential. Oil viscosity affects the amount of torque that is needed to crank the engine. Refer to the Operation and Maintenance Manual, "Fluid Recommendations" for the recommended viscosity of oil.Lubricating Oil Heaters
Note: Oil pan immersion heaters are not recommended for heating the lube oil. To ensure the compatibility of the components, only use equipment that is recommended by Caterpillar.
Heating elements that are in direct contact with the lubricating oil can cause coking of the oil.To aviod coking of the oil when the oil is heated, follow these recommendations:The temperature of the heating surface must not exceed 150 °C (300 °F). The maximum heat density of the heating surface must not exceed 1.24 w/cm2 (8W/in2).
Engine oil pan heaters are useful devices that provide the following functions:
Assist in reducing the cold cranking amperage that is needed to start the engine.
Improve the flow of oil at start-up.
The time that is needed to warm up the engine is reduced.
The service life of bearings is increased.Engine oil pan heaters can reduce the minimum ambient temperatures that are normally recommended for multigrade oil. Consult your dealer for more information.Recommendations for the Coolant
Provide cooling system protection for the lowest expected outside temperature. Refer to the Operation and Maintenance Manual, "Fluid Recommendations" for the recommended coolant mixture.In cold weather, check the coolant often for the proper glycol concentration in order to ensure adequate freeze protection.Jacket Water Heater
A jacket water heater heats the coolant that surrounds the combustion chamber providing the following functions:
Startability is improved.
Warm up time is reduced.
The required temperature for ether is reduced.An electric jacket water heater can be activated once the engine is stopped. An effective jacket water heater is typically a 1500 W unit. Consult your marine dealer for more information.Idling the Engine
While the engine is idling, the application of a light load (parasitic load) will assist in maintaining the minimum operating temperature. The minimum operating temperature is 71 °C (160 °F). Maintaining an elevated low idle speed for extended periods will be easier with the installation of a hand throttle. An idle speed of 1200 rpm is preferred for all engines.Recommendations for Coolant Warm Up
Warm up any system that has cooled below normal operating temperatures due to inactivity. The warm-up should be performed before the engine is returned to full operation. During operation in very cold temperature conditions, damage to engine valve mechanisms can result from engine operation for short intervals. This damage can happen if the engine is started and the engine is stopped many times without being operated in order to warm up completely.When the engine is operated below normal operating temperatures, fuel and oil are not completely burned in the combustion chamber. This fuel and oil causes soft carbon deposits to form on the valve stems. Generally, the deposits do not cause problems and the deposits are burned off during operation at normal engine operating temperatures.When the engine is started and stopped without operating long enough to warm up completely, the carbon deposits become thicker. The carbon deposits will cause the following problems:
Free operation of the valves is prevented.
Valves become stuck.
Pushrods are bent.
Other damage to valve train components can result. For this reason, when the engine is started, the engine must be operated until the coolant temperature is 71 °C (160 °F) minimum. Carbon deposits on the valve stems are kept at a minimum and the free operation of the valves and the valve components are maintained.Warm the engine thoroughly to keep other engine parts in better condition. The service life of the engine will be extended. Lubrication will be improved. There will be less acid and less sludge in the oil. The better condition of the oil will provide longer service life for the engine bearings, the piston rings, and other parts. However, limit unnecessary idle time to 10 minutes. Engine wear is greatest at low idle and unnecessary idling wastes fuel.