Servicing Engine-Related Components; Cooling System; Figure 5.1 Cooling Circuit - Carrier Supra 950MT Operation & Service Manual

5.2

SERVICING ENGINE-RELATED COMPONENTS

5.2.1

Cooling System

The condenser and radiator can be cleaned at the same time. The radiator must be cleaned internally as well as
externally to maintain adequate cooling.
The condenser and radiator are incorporated into a single assembly. The condenser fans draw the air through the con-
denser and radiator coil. To provide maximum air flow, the condenser fan belt should be checked periodically and
adjusted if necessary to prevent slippage.
Use only ethylene glycol antifreeze (with inhibitors) in system as glycol by itself will damage
the cooling system. Always add pre-mixed 50/50 antifreeze and water to radiator/ engine. Never
exceed more than a 50 percent concentration of antifreeze. Use a low silicate antifreeze.
1. Remove all foreign material from the radiator/condenser coil by reversing the normal air flow (Air is pulled in
through the front and discharges over the standby motor). Compressed air or water may be used as a clean-
ing agent. It may be necessary to use warm water mixed with any good commercial dish washer detergent.
Rinse coil with fresh water if a detergent is used.
2. Drain coolant by removing the lower radiator hose and radiator cap.
3. Install the hose and fill system with clean, untreated water to which three to five percent of an alkaline based
radiator cleaner should be added (six ounces - dry 151 grams to one gallon = 3.78 liters) of water.
4. Run the engine 6 to 12 hours and drain the system while warm. Rinse system three times after it has cooled
down. Refill system with water.
5. Run the engine to operating temperature. Drain the system again and fill with treated water/antifreeze.
NEVER POUR COLD WATER INTO A HOT ENGINE. However, hot water can always be added to
a cold engine.
WTS
(Water Temperature Sensor)
Coolant pump
CAUTION
!

Figure 5.1 Cooling Circuit

Thermostat
Coolant Outlet
(Hot Side)
Coolant Inlet (cold inside)
Pressure Cap
Overflow Tank
5-3 62-11863