2000 Mercury Mystique Owner's Manual - Page 177

Maintenance and care After any coolant has been added, check the coolant concentration (see Checking engine coolant section). If the concentration is not 50/50 (protection to -34°F /-36°C), drain some coolant and adjust the concentration. It may take several drains and additions to obtain a 50/50 coolant concentration. Whenever coolant has been added, the coolant level in the coolant reservoir should be checked the next few times you drive the vehicle. If necessary, add enough 50/50 concentration of engine coolant and distilled water to bring the liquid level to the proper level. If you have to add more than 1.0 liter (1.0 quart) of engine coolant per month, have your dealer check the engine cooling system. Your cooling system may have a leak. Operating an engine with a low level of coolant can result in engine overheating and possible engine damage. Changing engine coolant Change your engine coolant according to the appropriate schedule listed in the "Scheduled Maintenance Guide". It is important that the engine coolant be changed at the specified intervals. The corrosion protection of engine coolant is depleted with time and usage. Use of engine coolant with depleted corrosion protection may result in damage to the coolant system. Color, specific gravity and freeze point of the coolant are not indicators of depletion. To find out how much fluid your vehicle's cooling system can hold, refer to the Refill capacities in the Capacities and Specifications chapter. Fill your coolant reservoir following the directions given in the Adding engine coolant section. Coolant usage in severe winter climate If you drive in extremely cold climates less than -34°F (-36°C), it may be necessary to increase the coolant concentration above 50 %. Refer to the chart on the coolant container to ensure the coolant concentration in your vehicle will provide adequate freeze protection. Never increase the engine coolant concentration above 60 % (protection to -60°F). At a level over 60 %, your engine could overheat and become damaged. Coolant usage in hot climate If you drive in hot climates, it is still necessary to maintain the coolant concentration at 50/50 coolant and water. Do not allow the concentration to fall below 40 % coolant. At a concentration less than 40 %, the corrosion protection to your engine and cooling components may be compromised and permanent damage may result. 177