Mechanical
The 600's great size, weight, and numerous hydraulically driven amenities required more power than Mercedes' largest engine at that time, the 3-litre 6-cylinder M189, could produce. A new V8 with more than twice the capacity was developed, the 6.3 l M100. It featured a single overhead camshaft (SOHC) per cylinder bank and a Bosch-made intermittent 8-point mechanical fuel injection, and developed 250 PS.[11]
Originally, chief engineer Fritz Nallinger overseeing the design envisioned two models: base model was to be 500, referring to the original 5-litre capacity of the V8 engine; and top model 750 was to feature a 7.5-litre V12, the design of which was assigned to engine designer Adolf Wente. The engine, codenamed M101, was to share the 90-degree bank angle with the V8 engine, with every cylinder bank having a single chain-driven overhead camshaft, opening in-line valves, and a Bosch fuel injection pump located in the central vee, with twin ignition distributors, the power was intended to be around 380-400 bhp. However, as the V8 engine was eventually enlarged to 6.3 litres, the V12 was rendered redundant and never entered production.[12]
The 600 used what Mercedes referred to as the comfort hydraulic system ,[13] which was made specifically for the 600 in conjunction with Bosch. The system was extremely complex, utilizing pressurized hydraulic fluid to control the cars windows, seats, optional sunroof, boot lid, ventilator flap, and air conditioning. On early models, this system was also able to pull the doors in if they weren't fully latched, acting as an early form of self closing doors.
The closed loop hydraulic system was powered by an engine driven pump that pressurized the fluid to around 150 bar. When a switch for a hydraulically controlled amenity was pressed, it would activate a control valve that would allow the fluid to transfer energy to the pistons that powered said amenity. There was a nitrogen-filled accumulator present to maintain some hydraulic pressure when the car was off. The hydraulics gave the amenities of the 600 unusually quick and quiet operations compared to the more traditional vacuum and electrical setups of other luxury cars. The hydraulics require attentive maintenance, as a leak in any of the lines could lead to amenities not working as they should and eventually a complete failure of the system. Mercedes offered an optional 'hydraulic repair kit' with special tools that owners could use in the event of a minor hydraulic failure.[14]
The suspension of the 600 was not fully hydraulically controlled, as Citroën owned a patent for a hydropneumatic suspension system at the time. Instead, the 600 used a load leveling air suspension system similar to the Mercedes-Benz W112. Like the Komfort Hydraulik System, the air suspension was pressurized using an engine driven pump. The suspension had multiple settings that the driver could control from a switch on the steering column. These include 'N-mode' (for normal driving), 'H-mode' (increases ride height by 50 mm) and 'S-mode' (disables air suspension for servicing). Unlike the other Mercedes models with this system, the 600 also uses the air pressure pump to control brake boosting. In the event of an air system failure, the brakes are designed to take priority over the air suspension and can even pull from the suspensions air supply in low pressure situations.[15] The adjustable air suspension delivered excellent ride quality and sure handling over any road surface.[16] It even beat lap times of the Mercedes-Benz 230SL.[13]
