Engine: Description and Operation

CONSTRUCTION
The skirted design crankcase is manufactured in cast aluminium alloy with shrink fit dry cast iron cylinder liners. The crankshaft is manufactured from forged steel and is nitro-carburize treated to enable a very high quality finish on the bearing surfaces and increase the life of the journals. The crankshaft is supported by seven iron bearing caps having bearings, which are lead bronze on split steel backed shells with a lead indium overlay. Crankshaft end float is controlled by half thrust washers fitted on each side of the center main bearing journal.

The connecting rods are manufactured from manganese molybdenum steel, forged in an 'H' section. The small end bushes are lead bronze with steel backing, machined to size after being pressed into the connecting rods. The big end bearings are of a lead bronze alloy on split steel backed shells and with lead indium overlay.

The pistons are manufactured from aluminium alloy and have a spring assisted micro land oil control ring situated below a barrel-faced internally tapered chrome plated compression ring and an externally stepped taper-faced secondary ring. The pistons are internally strutted for thermal control and run on hardened steel gudgeon pins offset from the center line of the piston towards the thrust face.

The cylinder head is cast from aluminium alloy with pent-roof shaped combustion chambers with cross-flow valve porting.

Running directly in the cylinder head are two cast iron camshafts retained by machined aluminium caps. Each camshaft uses chilled cams to drive two valves per cylinder via chilled cast iron bucket tappets with shim adjustment. Control of each of the four valves per cylinder is maintained by single valve springs.

The camshafts are operated by a two stage 'duplex' chain drive from the crankshaft. Each stage is controlled by a hydraulic tensioner operating through a pivoted rubber-faced curved tensioner blade. The first stage incorporates a three point drive via the crankshaft, intermediate shaft and auxiliary shaft. The intermediate shaft is live and provides a 0.75 x crankspeed drive through the timing cover. This drive access is blanked off.

The 'live' auxiliary shaft is driven at crankshaft speed and is situated on the RH side of the engine (looking from rear). In addition to driving the distributor via a set of 2:1 reduction spiral gears, it provides an external drive for the power assisted steering pump at the rear.

The second stage is a three point drive via the intermediate shaft and two camshafts. The 2:1 reduction ratio from crankspeed is achieved by the combined ratio of the intermediate and camshaft sprockets sizes.

The oil pump is a rotor-type mounted on the underside of the front of the crankcase and driven by a 'simplex' chain from the crankshaft nose. The pump incorporates a built-in pressure relief valve. Below the line of the crankcase are two windage trays; these prevent oil being sucked up and thrown into the crankcase thereby alleviating windage and power losses. Above the sump oil level is a sump tray and baffle assembly to prevent oil surge.

At the rear of the crankshaft is a new design of lip-type oil seal which provides a high degree of oil retention. It also allows the use of higher engine speed and easier serviceability as opposed to conventional asbestos rope seal.

4.0 Liter Engine:

1 AUXILIARY SHAFT
2 AUXILIARY SHAFT REAR SEAL
3 CAM SHAFTS
4 CAMSHAFT COVER GASKET
5 CONNECTING ROD BEARING ENGINE SET
6 CRANKSHAFT
7 CRANKSHAFT PULLEY
8 CRANKSHAFT END FLOAT
9 CRANKSHAFT FRONT OIL SEAL
10 CRANKSHAFT REAR OIL SEAL
11 CYLINDER HEAD CASTING
12 CYLINDER HEAD
13 CYLINDER HEAD GASKET
14 CYLINDER PRESSURES
15 ENGINE ASSEMBLY
16 ENGINE ASSEMBLY
17 ENGINE DRIVE PLATE (AUTO)
18 ENGINE FLYWHEEL(MANUAL)
19 ENGINE MOUNTING AND BRACKET-FRONT LH
20 ENGINE MOUNTING AND BRACKET-FRONT RH
21 ENGINE MOUNTING-REAR
22 ENGINE OIL
23 ENGINE REAR/TRANSMISSION ADAPTOR PLATE
24 MAIN BEARING-ENGINE SET
25 OIL COOLER
26 OIL COOLER HOSE-RETURN
27 OIL COOLER HOSE-SUPPLY
28 OIL FILTER CANISTER
29 OIL FILTER HEAD GASKET
30 OIL PICK UP STRAINER
31 OIL PRESSURE RELIEF VALVE ASSEMBLY
32 OIL PRESSURE TRANSMITTER
33 OIL PUMP
33 OIL PUMP
34 OIL PUMP PIPE O-RINGS
35 OIL SUMP GASKET
36 PISTON AND CONNECTING ROD-ENGINE SET
37 TIMING CHAIN DAMPERS-ENGINE SET
38 TIMING SPROCKET-INTERMEDIATE
39 TIMING CHAIN AND TENSIONER-LOWER
40 TIMING CHAIN AND TENSIONER-UPPER
41 TIMING CHAIN, GEAR AND TENSIONER ENGINE SET
42 TIMING COVER GASKET