Brief description
The coolant circuit is designed to provide long-term protection against frost and corrosion. The design of the M57 is identical to that of the M51 and in the M67 to that of the M62.
The cooling system has been adapted to the new requirements concerning the cooling capacity and the modified environment (common rail, injection system).
Requirements and Objectives
The following requirements and objectives apply to the cooling system:
• Requirements
– Adaptation to injection system (common rail)
– Simple design (same concept as M51 and M62)
– All connection points for water-carrying hoses designed as plug-in connections as on the M47
– Further reduction of emissions and fuel consumption
• Objectives
– Provision of optimum cooling capacity under all operating conditions
– Easy-to-service layout
System structure
The cooling system consists of following components:
• Water pump
• Thermostat
• Radiator
• Fan/shroud
• Auxiliary heater
• Independent park heating option
The various coolant circuits can be subdivided into several part circuits:
• Engine
• Heating
• Expansion tank
• Engine oil cooler (M57 only)
• Alternator (M67 only)
• EGR cooler (M67 only)
