Engine description Coolant diagram 20 © 2009 1 Cooler 2 Coolant inlet 3 Coolant pump 4 Coolant partial flow to the lubricating oil cooler 5 Lube oil cooler 6 Coolant supply for engine cooling 7 Cylinder pipe/head cooling 8 Connection possibility for cab heating 9 Heat exchanger 10 Return line 11 Coolant return to thermostat 12 Coolant outlet 13 Compensation line 14 Venting pipe 2 Coolant schematic (example)