Lubrication system

Design and Function

Applies to: 2001–2006; D5244T, D5244T2, D5244T3

Lubrication system

Components

Inlet line with strainer

Prevents large particles from reaching the oil pump.

Oil pump

The oil pump is an internal gear pump (duocentric) with an integrated safety valve. The valve opens at approximately 800 kPa. It prevents excessively high pressure which could damage the oil cooler for example.

Bleed valve

To ensure that there is no air in the lubrication system there is a valve positioned immediately after the oil pump. During the pressure build up, the air is led out into the oil pan. This continues until its valve closes at approximately 40 kPa.

Oil cooler

The oil cooler is a plate oil cooler. The space for oil and coolant is divided up alternatively using plates. In total 16 plates are used.

Relief valve

Piston type relief valve. Opens at approximately 550 kPa.

Limits the maximum pressure in the engine.

By placing a relief valve after the oil cooler any excess oil that is also led out to the oil pan is also cooled.

Oil filter

The oil filter is a loose filter element in a housing. The by-pass valve used in the event of a blocked filter is in the cover.

Main oil channel with oil pressure switch

Supplies oil to the main bearings and connecting rod bearing.

The oil pressure switch opens / closes at approximately 60 kPa.

Turbocharger (TC) inlet

Supplies the turbocharger (TC) with oil.

Inlet valve for piston cooling

The valve opens / closes at approximately 135 kPa.

If the opening pressure is too high the oil flow to the pistons is reduced which may result in damage to the engine.

If the opening pressure is too low the flow for piston cooling increases. In certain situations (before the relief valve has opened), this may result in the engine oil pressure being too low which may cause damage to the engine.

Piston cooling nozzles

The nozzles guide the oil towards the inlet for the piston ring carrier.

Other

Cylinder head gasket

The cylinder head gasket has a calibrated hole for the inlet to the cylinder head. This is to limit high pressure in the cylinder head.

Lubrication

Connecting joint, low / high pressure pump: oil is led to the connecting joint for the diesel pump via the intake camshaft.

Vacuum pump;·oil is led to the vacuum pump via the exhaust camshaft.

Hydraulic unit for valve adjustment

Two front-rear ducts in the cylinder head supply the cam bearings and the hydraulic units with oil.

Pressure controlled crankcase ventilation, oil separator

The crankcase ventilation is pressure controlled using a cyclone type oil separator.

The crankcase gases are led in from the crankcase and cylinder head. On their way to the pressure regulator, the gases are forced passed two cones positioned in the housing. By leading the gases around the cones, the speed is increased and the oil in the gases is thrown out towards the walls and condensates. The oil then returns to the oil pan.

To prevent freezing, the outlet (at the inlet for the turbocharger) has a positive temperature coefficient (PTC) element for heating.