MAINTENANCE AND LUBRICA TION 251

Refilling the Cooling System

Close all drain cocks and fill with the proper coolant mixture. Run engine with the pressure cap removed until operating temperature reached and the thermostat opens. Recheck level and add coolant required. Run the engine long enough sure the system free air and has the correct amount coolant.

Protecting the Cooling System CAUTION

The concentration ethylene glycol opylene glycol the cooling system must checked with a r efractometer prior traveling operating eas wher e subfr eezing temperatur may encounter When adding antifr eeze the run the engine for minutes befor e checking with a r efractometer

Note: Y our chassis currently supplied from the factory with engine coolant protection –23°C (–10°F). Optional coolant protection –40°C (–40°F) also

Ethylene glycol propylene glycol - based antifreezes are both approved for all MACK All ethylene glycol and propylene glycol coolants must low - silicate antifreezes which meet ASTM4985 test (GM6038M SPEC) These antifreezes are sometimes referred heavy - duty diesel Passenger car coolants NOT meet this sure maintain the required level antifreeze protection for anticipated winter temperatures your area operation. A 40% 60% concentration antifreeze required for engines, regardless application, geographic location ambient air temperature.

Caution

NOT exceed a 60% concentration antifr eeze water . A higher per centage antifr eeze will not incr ease otection. Concentrations over 60% adversely affect eeze otection and heat transfer

Note: Propylene glycol should checked with a refractometer .