N38143 Chapter 4 Keel cooling connections - 4.4TWGM and 4.4TW2GM These engines require two keel coolers and do not have a header tank as part of the engine package, but have a remotely mounted expansion tank. Figure (F) shows the connections and flow. Connections sizes are 38mm (1.5 ins) for the water jacket circuit and 32mm (1.25 ins) for the aftercooler circuit. 1. 2. 3. 4. Connections Flow Keel cooler Remote tank 5. 6. 7. 8. Fresh water pump Thermostat Engine Integral engine oil cooler 9. 10. 11. 12. Exhaust manifold Aftercooler Bleed Raw water pump Page 23