Coolant Replacement And Cleaning Of Cooling System; Draining Of Coolant; Cleaning Procedure - Mitsubishi 6M60-TL Service Manual

GENERAL INSPECTION AND ADJUSTMENT

1. Coolant Replacement and Cleaning of Cooling System

• Using the radiator for extended periods of time without cleaning can increase chance of rust and scale formation,
which may cause engine overheating. The cooling system must be cleaned periodically.
Tightening torque (Unit: N·m {kgf·m})
Mark
– Radiator drain cock
– Crank case drain cock

1.1 Draining of coolant

1.2 Cleaning procedure

CAUTION
• Water used for flushing the cooling system must be soft water that has a property meeting the require-
ments indicated below. Using hard water will cause scale and rust to form in the system.
Required properties of soft water
Total hardness .......................... 300 ppm or less
Sulfate SO .............................. 100 ppm or less
4
Chloride CI ............................. 100 ppm or less
Total dissolved solids.............. 500 ppm or less
pH .............................................. 6 to 8
• Keep the coolant temperature at approximately 90°C so that the thermostat valve remains open and coolant con-
tinues to circulate in the radiator.
• For the sake of convenience you can raise the coolant temperature quickly by covering the front of the radiator
with corrugated cardboard or something similar.
• In cases where a great amount of rust has accumulated it is common for the radiator to leak as a result of clean-
ing. Conduct a through check for leakage after cleaning.
14-6
Parts to be tightened
• Before draining the coolant, loosen the pressure cap to reduce
the pressure in the cooling system. Remember to drain the cool-
ant out of the reservoir tank as well.
WARNING
• Drain the coolant only after it has cooled sufficiently to
avoid getting scalded.
• Opening the pressure cap while the coolant temperature is
still high can cause hot coolant to spray out. Cover the
pressure cap with a cloth, and loosen it slowly to let the
pressure out before opening it fully.
Tightening torque
2 {0.2}
7 {0.7}
Remarks
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