Pipes and hoses (Cooling system - Td5)

Pipes and hoses

The coolant circuit comprises flexible hoses and metal formed pipes which direct the coolant into and out of the engine, radiator and heater matrix. Plastic pipes are used for the bleed and overflow pipes to the expansion tank.

A bleed screw is installed in the radiator top hose and is used to bleed air during system filling. A drain plug to drain the heater and cylinder block circuit of coolant is located on the underside of the coolant pump feed pipe.

Oil cooler

The oil cooler is located on the left hand side of the engine block behind the oil centrifuge and oil filter. Oil from the oil pump is passed through a heat exchanger which is surrounded by coolant in a housing on the side of the engine.

Full water pump flow is directed along the cooler housing which also distributes the flow evenly along the block into three core holes for cylinder cooling. This cools the engine oil before it is passed into the engine. A small percentage of the coolant from the oil cooler passes into a metal pipe behind the engine. It then flows into the lower radiator via a hose.

Fuel cooler

The fuel cooler is located on the right hand side of the engine and is attached to the inlet manifold. The cooler is cylindrical in design and has a coolant feed connection at its forward end. A 'T' connection at the rear of the cooler provides a connection for the coolant return from the heater matrix and coolant return from the fuel cooler.

The 'T' connection houses a thermostat which opens at approximately 82°C. This prevents the cooler operating in cold climates.

Two quick release couplings on the cooler allow for the connection of the fuel feed from the pressure regulator and return to the fuel tank. A counter flow system is used within the cooler.

Fuel flows around a coolant jacket within the cooler and flows from the back to the front of the cooler. As the hot fuel cools travelling slowly forwards it meets progressively colder coolant travelling in the opposite direction maintaining a differential cooling effect.

EGR Cooler

The EGR Cooler is mounted on the front of the cylinder head. Coolant from the oil cooler flows around the EGR cooler, cooling the exhaust gas, to improve exhaust emissions, before being returned to the expansion tank.

Coolant pump

1 Drive lugs (hidden) 2 Housing 3 'O' rings

4 Cover 5 Feed hose connection 6 Impeller