VIII. SERVICE AND MAINTENANCE

Cooling System

COOLANT TYPE - Your cooling system should always be sufficiently charged with an adequate mixture of antifreeze and water, regardless of the climate, in order to maintain a broad operating temperature range. Your cooling system has been factory-charged with an ethylene glycol-based antifreeze.

NOTE:

Ethylene glycol-based antifreeze and propylene glycol-based antifreeze should never be mixed.

CHECKING CONCENTRATION - The radiator cap is located immediately behind the rear of the cab (fig. 8.4). Never remove a cap from a hot engine. Always allow the engine to cool before servicing cooling system.

A 50/50 antifreeze/water mixture is a conservative mixture which allows good protection against both overheating and freezing. If a stronger antifreeze mixture is required, be sure not to exceed the engine manufacturer’s guidelines for antifreeze mixing. The table in figure 8.6 gives a few examples of ethylene glycol antifreeze/water mixture protection values. Consult the engine manufacturer’s handbook for further information.

50%

Concentration should be checked every 500 hours or at the beginning of each winter, whichever comes first. It should be checked using a refractometer; “floating ball”-type density testers or hydrometers are not accurate enough for use with heavy duty diesel cooling systems.