GILLIG LOW FLOOR, Руководство по обслуживанию

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Engine
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Draining the Cooling System
Coolant drain points are provided at the thermostat housing, engine, radiator, coolant pipes, air compres-
sor, transmission oil cooler, and in the heating system. When the solenoid valve in the heater supply line
and the gate valves in the water return lines are closed, the cooling system can be drained without having
to drain the heater lines. To drain the system:
When draining the coolant system, do not allow the cooling system to
dry out and do not remove the coolant filter.
Coolant is under pressure and extremely hot after the engine has been
running. To avoid the possibility of being sprayed with hot coolant, wait
until boiling stops and the engine has cooled before pressing the relief
valve.
1. Press and hold the relief valve (vent cock) at the surge tank to relieve pressure from the system.
2. When all pressure and steam have escaped from the system, pull the handle until the cap is
opened to the limit of the safety catch. Release the safety catch and completely open the cap.
Block it open to vent the cooling system while draining.
3. Place a suitable container underneath the drain cock. A large container is necessary, as the system
holds approximately 20 gallons of coolant.
The coolant may be very hot. Take precautions to avoid hot coolant
touching your skin.
4. Open the drain cock on the lower coolant pipe and the remove the coolant drain plug from the
radiator. Allow the system to drain.
5. Dispose of used coolant in accordance with environmental regulations.