General
The 2.0L Duratorq TDCi (DW10) engine uses the Siemens common rail direct fuel injection process.
The cylinder head is made of two parts. The upper and lower parts are made of aluminium and are bolted to each other. The lower section houses four valves per combustion chamber and the valve gear and camshafts.
The valves are actuated by means of two overhead camshafts and roller followers with hydraulic tappets.
The exhaust camshaft and the coolant pump are driven by a toothed belt. The fuel pump is flange-mounted directly onto the exhaust camshaft. The exhaust camshaft drives the inlet camshaft via a short timing chain.
The oil pump is located inside the oil pan and is driven by the crankshaft via an oil pump chain.
The vacuum pump is flange-mounted onto the inlet camshaft and is driven directly.
Engine identification
NOTE:Cylinder 1 is located on the transmission side.
The serial number of the engine and the engine code are located on the intake side of the cylinder block (in line with the second cylinder).
The valve cover and the inlet manifold form one assembly and are made of plastic.
The PCV valve is also located on the valve cover.
It is sealed off from the cylinder head with a separate seal.
The cylinder head's intake ports and injector ports are each sealed off from the inlet manifold by four sealing rings.
NOTE:Refer to the current service literature for precise details of how to assemble the valve cover and inlet manifold.
Before re-installing the valve cover and the inlet manifold, carefully check the sealing rings for damage and renew if necessary.
Cylinder head
2
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Cylinder head upper part
3
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Cylinder head lower part
NOTE:The upper and lower parts of the cylinder head are matched to each other and cannot be renewed separately.
NOTE:It is important to ensure that the oil supply holes are not blocked by sealant when the two parts of the cylinder head are brought together.
The cylinder head is made of two separate parts. This special design ensures that the overall structure is stronger.
The upper and lower parts of the cylinder head are milled in a single operation and are accurately positioned with two alignment sleeves.
The lower part of the cylinder head is bolted to the cylinder block.
The upper halves of the camshaft mountings are incorporated into the upper part of the cylinder head. Here the camshafts run directly in aluminium, without additional bearing shells.
The upper part of the cylinder head features top-entry intake ports.
The two individual parts are sealed using a one-component, silicone-based sealant when they are joined together.
Valve train
The inlet valves are made entirely of one material. The heads and stems of the exhaust valves are manufactured from different materials and are joined to one another by means of friction welding.
By using roller followers, it has been possible to keep valve actuation friction losses low.
Valve clearance adjustment is done automatically by the hydraulic tappets. As a result, there is no need to adjust the valve clearances.
The hydraulic tappets are connected with the engine's oil circuit by oil ports cast into the cylinder head.
Camshafts
The inlet and exhaust camshafts are made from steel tubes. The cams and ends of the camshaft are shrunk on.
Each camshaft runs directly in aluminium in five bearings, without additional bearing shells.
The vacuum pump is flange-mounted onto the rear of the inlet camshaft and is driven directly.
The fuel pump is flange-mounted onto the rear of the exhaust camshaft and is also driven directly.
Camshaft drive
3
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Crankshaft timing pulley
NOTE:A spacer shim is located between the cylinder block and the idler pulley (2); this must be re-fitted when carrying out installation work.
The exhaust camshaft is driven by a toothed belt. The toothed belt also drives the coolant pump.
The toothed belt drive has an automatic tensioning pulley. The tensioning pulley operates by spring force.
A feather key specifies the installation position of the exhaust camshaft timing pulley and the crankshaft timing pulley.
A hole is located on the exhaust camshaft timing pulley into which can be inserted the timing pin (special tool) to adjust the timing.
Timing chain tensioner
1
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Timing chain tensioner housing
The timing chain guide is made of plastic.
Timing chain guide wear is compensated for by a spring loaded timing chain tensioner.
Because the timing chain tensioner is connected to the engine oil supply circuit, the components are lubricated and chain noise is reliably prevented.
A second timing chain guide is attached to the cylinder head lower section.
Timing chain
The light alloy pistons have a combustion chamber incorporated into the centre of the piston crown. This optimises swirling of the fuel/air mixture.
Two recesses are incorporated into each piston crown.
In order to minimise friction, particularly during the running-in phase, the piston stem has a graphite-based coating.
The piston pin is a floating fit and is held in position by two snap rings.
Cylinder block
NOTE:Refer to the current service literature for the exact procedure and the correct measurements for machining.
The cylinder block is made of cast iron and has no cylinder liners.
The running surfaces of the cylinders are worked directly into the cylinder block.
The mating face of the cylinder block with the cylinder head can be re-worked.
Two holes are provided in the cylinder block, for the guide sleeves used to secure the cylinder head gasket.
Connecting rods
NOTE:Refer to the current service literature for the exact procedure and the correct tightening torques for installing the big end bearings.
The connecting rods are made of forged steel.
The big-end bearing caps are cut and machined at the joins to the connecting rod.
The big end bearing shells have retaining lugs to prevent radial movement.
The retaining nuts are tightened in three stages. In the third stage the nuts are tightened to a specified angle.
The connecting rods and big-end bearing caps are paired and must not be mixed up.
Crankshaft main bearings
For accurate adjustment of the crankshaft bearing clearance, the crankshaft bearing shells in the crankshaft main bearing caps are available in five different thicknesses.
The upper crankshaft main bearings (cylinder block side) are only available in one thickness.
Marks on the cylinder block (1) and on the crankshaft (timing side) (4) indicate the thicknesses of the crankshaft bearing shells installed.
The barcode (2) is for production and the alphanumeric code (3) for service operations.
Retaining lugs on the crankshaft bearing shells prevent radial movement.
NOTE:The crankshaft main bearing caps must be installed in the correct position.
NOTE:Cylinder 1 is located on the transmission side.
Numbers on the crankshaft main bearing caps specify where they should be installed. When installing them, the crankshaft main bearing cap marked "1F" must be nearest the transmission.
Axial play is restricted by means of two thrust plates on the crankshaft main bearing of cylinder 1.
The thrust plates have lubricating grooves which must be pointing towards the main bearing when installing them.
Oil pump
The oil pump is located on the front face of the engine and is housed inside the oil pan.
It is a rotor pump and is driven by the crankshaft via a short oil pump chain.
An oil pressure control valve is incorporated in the oil pump housing. It opens when the oil pressure reaches about 8 bar.
Oil filter/oil cooler unit
The oil cooler is an oil/coolant heat exchanger.
The oil filter/oil cooler unit is located on the side of the cylinder block in line with cylinder 2.
The oil filter element has a blanking plug which seals off the drain hole in the oil filter housing.
When changing the oil filter cartridge, the plug is removed with the oil filter cartridge. The oil can return to the oil pan through the housing, so that no pollution can be caused by leaking oil.
The oil filter/oil cooler unit is connected directly with the engine's coolant circuit by means of an adapter and connecting hose.
The piston skirts are cooled from below using oil from the oil spray tubes. The oil spray tubes are secured in the cylinder block with banjo bolts.
The banjo bolts are connected to the engine oil circuit.
Valves are built into the banjo bolts, and from a minimum oil pressure of about 0.5 bar they supply the oil spray tubes.