Cooling System; General Information; Maintenance - Toro 520XI Service Manual

DIESEL ENGINE

COOLING SYSTEM

General Information

A belt driven water pump circulates coolant
through passages in the engine block and
cylinder heads. The coolant carries engine heat
to a radiator which transfers the heat stored in
the coolant to the surrounding air by drawing
the cooler ambient air through fins in the
radiator with the fan.
Engine temperature is maintained by a
thermostat which opens at approximately 180°
F (82° C). When the thermostat is open, it
allows coolant to flow through the radiator.
When the coolant temperature falls below 180°
F (82° C), the thermostat closes, bypassing the
radiator allowing faster warm-up and consistent
operating temperature.
The cooling system is pressurized at operating
5
temperature to prevent evaporation and raise
the boiling point of the coolant.

Maintenance

Inspect cooling system often. Carefully clean
grass clippings and other debris from air intake
screens and radiator fins.
Maintain coolant level in the coolant recovery
tank between the two lines with a 50/50 mix of
antifreeze and water.
Caution: Do not remove the radiator cap
when the engine is hot. Discharge of hot
coolant can cause severe burns.
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2.7163.26
2.0757.030
5xi Series Tractor Service Manual