Cylinder Head Components
| ITEM | DESCRIPTION |
|---|---|
| 1 | Bolt (4 of) |
| 2 | Front lifting eye |
| 3 | Rear lifting eye |
| 4 | Bolt (4 of) |
| 5 | Camshaft cover stud (6 of) |
| 6 | Camshaft cover bolt (7 of) |
| 7 | Intake manifold camshaft cover assembly |
| 8 | Gasket |
| 9 | Cylinder head |
| 10 | Plug (coolant) |
| 11 | Plug (oil port) |
| 12 | Camshaft bearing cap (7 of) |
| 13 | Bolts (18 of) |
| 14 | Camshaft bearing cap and seal housing (2 of) |
| 15 | Intake camshaft |
| 16 | Seal |
| 17 | Cylinder head bolts (8 of) |
| 18 | Exhaust camshaft |
| 19 | Secondary timing chain |
| 20 | Seal |
| 21 | Cylinder head gasket |
| 22 | Plug (oil port) |
| 23 | Plug (coolant) |
| 24 | Plug (oil port) |
Cylinder Heads
| ITEM | DESCRIPTION |
|---|---|
| 1 | Blanking plug - coolant (2 of) |
| 2 | Cylinder head bolt (8 of) |
| 3 | Exhaust manifold stud (6 of) |
| 4 | Cylinder head dowel |
| 5 | Cylinder head dowel |
The cylinder heads are unique to each cylinder bank. Eight deep-seated bolts help reduce distortion and secure each cylinder head to the cylinder block. The cylinder head bolts are located beneath the camshafts, four under the intake camshaft and four under the exhaust camshaft. Two hollow dowels align each cylinder head with the cylinder block.
The cylinder head gasket is available in five different thicknesses. The choice of gasket thickness is dependent on the maximum piston protrusion. Gasket thickness is identified by serrations cut into the front end of the gasket. For additional information, Refer to: SPECIFICATIONS
The cylinder head has four ports machined at each cylinder location, two exhaust ports and two intake ports. One of the intake ports is helical and functions as a swirl port, the other is arranged laterally as a tangential port and functions as a charge port.
The camshafts are of a hollow tube construction, with pressed on lobes. Each camshaft is retained by caps, five for the exhaust camshafts and four for the intake camshafts. Location letters, A to I for the intake camshaft and R to Z for the exhaust camshaft, are marked on the outer faces of the caps for each cylinder head.
High Pressure (HP) Fuel Pump Drive
| ITEM | DESCRIPTION |
|---|---|
| 1 | Bolt |
| 2 | Camshaft gear |
| 3 | Toothed belt |
| 4 | Left cylinder head exhaust camshaft |
| 5 | High Pressure (HP) fuel pump |
| 6 | High Pressure (HP) fuel pump gear |
| 7 | Nut |
| 8 | Bolt |
| 9 | Tensioner |
| 10 | Bolts |
The left cylinder bank exhaust camshaft is machined to accept a rear camshaft gear. The rear camshaft gear provides drive for the High Pressure (HP) fuel pump.
The HP fuel pump drive incorporates the following main components:
- Camshaft gear
- HP fuel pump gear
- Toothed belt
- Tensioner.
For additional information, Refer to: FUEL CHARGING AND CONTROLS
The exhaust camshaft gear of the Bank 2 cylinder head also incorporates a reluctor ring, which is used in conjunction with the Camshaft Position Sensor (CMP) to measure engine position. For additional information, Refer to: ELECTRONIC ENGINE CONTROLS
The Bank 1 cylinder head exhaust camshaft is machined at the rear end to provide a drive connection for the vacuum and oil scavenge pump.
The fuel injection nozzles are centrally mounted above each cylinder. For additional information, Refer to: FUEL CHARGING AND CONTROLS
The glow plugs are arranged centrally on the intake side of the cylinder heads, between the two intake ports of each cylinder. For additional information, Refer to: GLOW PLUG SYSTEM
The engine lifting eyes are bolted to the cylinder head, one at the front and two at the rear of the engine, one per cylinder head.
Camshaft Covers
| ITEM | DESCRIPTION |
|---|---|
| 1 | Camshaft cover stud (8 of) |
| 2 | Camshaft cover - intake manifold assembly |
| 3 | Oil filler cap |
| 4 | Camshaft cover bolt (5 of) |
The Bank 1 camshaft cover incorporates an outlet for the full load engine breather and the engine oil filler cap. The Bank 2 camshaft cover incorporates an outlet for the part load engine breather. For additional information, Refer to: ENGINE EMISSION CONTROL
In-groove gaskets seal the joints between the camshaft covers and the cylinder heads. Together with spacers and seals on the camshaft cover fasteners, the gaskets are isolate the covers from direct contact with the cylinder heads, to reduce noise.
Intake And Exhaust Valves
| ITEM | DESCRIPTION |
|---|---|
| 1 | Valve spring collet - 24 of (12 per cylinder head) |
| 2 | Valve spring retainer - 24 of (12 per cylinder head) |
| 3 | Valve spring - 24 of (12 per cylinder head) |
| 4 | Valve stem seal - 24 of (12 per cylinder head) |
| 5 | Exhaust valve - 12 of (6 per cylinder head) |
| 6 | Intake valve - 12 of (6 per cylinder head) |
Each cylinder head incorporates two overhead camshafts operating four valves per cylinder via rocker arms with hydraulic valve tappets.
Rocker Arms And Hydraulic Valve Tappets
| ITEM | DESCRIPTION |
|---|---|
| 1 | Hydraulic valve tappet - 24 of (12 per cylinder head) |
| 2 | Rocker arm - 24 of (12 per cylinder head) |
The lightweight valve gear provides good economy and noise levels. Valve head diameters are 31 mm (1.220 in) for the exhaust and 35 mm (1.378 in) for the intake. All valves have 5 mm (0.197 in) diameter stems supported in seats and guide inserts. Valve spring collets, collars seats locate single valve springs on both intake and exhaust valves. Valve stem seals are integrated into the valve spring seats.