Part 1

Engine

Oil Filter and Cooler Assembly









The oil filter and cooler assembly is located at the front of the LH side of the cylinder block. The oil filter housing contains a separate single oil filter element. The oil filter supplies clean oil to the oil cooler, which is connected to the coolant system, and is further distributed to the various engine systems (For more information refer to the lubrication section).

Oil Pump Assembly









The oil pump is attached to bottom of the bedplate via a pivot pin and a bolt. The pump is an external gear wheel pump with integrated pressure control valve (for more information refer to the lubrication section).

Oil Pick-up









The fabricated steel oil pick-up is immersed in the oil reservoir to provide a supply to the oil pump during all normal vehicle attitudes. A mesh screen in the intake prevents debris from entering the oil system.

Oil Pan









The aluminium alloy structural oil pan is bolted to the bedplate.

NOTE:
The oil pan should always be fitted proud of the bedplate by 0.05mm (+0mm -0.05mm).
A combined oil level/temperature sensor is attached to the underside of the oil pan via 3 bolts. The tip of the sensor locates through an aperture and is sealed with an O-ring.









The engine oil drain plug is located on the exhaust side of the engine, towards the bottom of the oil pan.

Oil Level Gage









The oil level gauge locates along the intake side of the engine and is supported in a tube installed in the oil pan. A bolt securely attaches the tube to the engine oil cooler via a bracket. Two holes in the end of the gauge indicate the minimum and maximum oil levels. The difference between the dipstick markings, minimum and maximum, corresponds to 0.8 liters.

Starter Motor





The starter motor is located in a recess at the rear of the exhaust side of the oil pan. The motor, rated at 1.4 kW, uses permanent magnets instead of field windings to provide a low-weight starter motor; with the use of planetary gears to deliver a good torque to weight ratio For additional information, refer to Starting System - 3.2L Description and Operation.

CAMSHAFT TIMING COMPONENTS









The timing chain for the camshafts is located in a housing at the rear of the engine.

















The timing chain is driven by the camshaft chain gear via the crankshaft. The chain drives both the intake and exhaust camshafts. The chain is continually tensioned by a hydraulic chain tensioner and is lubricated by oil via a separate nozzle. The tensioner has an inhibitor that prevents the chain from slackening in the event of reversed loading.
The intake camshaft is equipped with a VCT unit and also drives the vacuum pump.
The return oil from the camshafts housing is routed to the gear housing and lubricates the timing gear's bearings and gear wheel.

LUBRICATION SYSTEM





The lubrication system components and functions are:
- Oil pick-up
- Oil pump
- Oil filter and cooler assembly
- Intake valve (piston cooling)
- Cylinder head oil supply
- Gear housing

Oil Pick-up
The oil pick-up contains a strainer, which separates large contaminants and prevents them from reaching the oil pump.

Oil Pump
The oil pump is an external gear wheel pump with integrated pressure control valve. The valve opens at approximately 4.5 bar and controls the system pressure.
The pump is driven by the crankshaft and is 1.3 times faster than the crankshaft.
To ensure that the air is released from the oil system, a valve is located in the oil pump on the pressure side. During the build-up of pressure, air is routed out into the crankcase. This continues until the valve closes at approximately 0.2 bar.

Oil Filter and Cooler Assembly
The majority of oil is routed to the oil filter, which is a separate single filter element located in the housing. The over-flow valve for the blocked filter is in the cover. The valve opens at approximately 2 bar.
There is a valve at the bottom of the housing. The task of the valve is to drain the housing of oil when the oil filter is removed. When the oil filter is installed, the valve is closed. A spring loaded ring at the bottom of the filter housing is affected by the actual filter. The ring is, in turn, mechanically connected to the valve.
When the filter is removed, the spring lifts the ring, which, in turn, opens the valve whereupon the oil drains to the oil pan.









The oil passes a non-return valve before it reaches the oil cooler/filter housing. The non-return valve ensures that the oil filter housing is not drained of oil when the engine is switched off. The valve opens at approximately 0.2 bar.
The oil first passes the oil cooler, a plate oil cooler. The chamber for oil and coolant is split alternately between the plates. There are 20 plates used in total. The first 16 plates are used for oil, which is routed through the engine's normal lubrication circuit, i.e. the oil is routed to the oil filter.
The 4 last plates are used to provide a proportion of the oil with extra cooling before it is routed onwards to cool the vibration damper. The circuit is calibrated to achieve correct flow.
There is a by-pass valve parallel to the oil cooler. The valve ensures an oil flow to the oil filter even if the oil cooler is blocked. The valve opens at approximately 2 bar.

Intake Valve (Piston Cooling)
The oil is also routed to the duct for oil cooling, which is parallel to the ducts for main bearings and connecting rod bearings.
The oil first passes a valve that opens/closes at approximately 2.0 bar. Thereafter, the oil is routed to the jets for piston cooling:
- If the valve has too high an opening pressure, this means that the oil flow to the pistons reduces, which can cause engine damage
- If the valve has too low an opening pressure, this produces an increased flow to piston cooling. It can, in certain situations (before the relief valve is opened) result in the engine's oil pressure being too low causing engine damage
The jets direct the oil towards the underneath of the pistons. Each cylinder has its own jet.

Cylinder Head Oil Supply
Oil is routed from the cylinder block through a front and rear duct to the cylinder head. The duct at the front edge supplies 2 circuits in the cylinder head with oil:

1. Circuit for the hydraulic tappets, vacuum pump and cam chain lubrication
A longitudinal duct on the intake side supplies the following components with oil:
- The hydraulic tappets
- The vacuum pump
- The nozzle for cam chain lubrication

2. Circuit for the intake camshaft's front bearing, the CPS valves and the tappets with CPS function
A duct supplies the intake camshaft's front bearing and both the CPS valves.
The front CPS valve controls the oil flow to the tappets for cylinders 1, 2 and 4 and the rear CPS valve controls the oil flow to the tappets for cylinders 3, 5 and 6.
When the CPS valve solenoids are activated, the valves open (i.e. shift from low to high valve lifting height) and the tappets are supplied with oil under pressure.
The longitudinal duct that supplies the rear CPS valve is equipped with a bleed hole. This is to ensure that no air reaches the CPS valves or the tappets.





The duct is also equipped with 2 calibrated passages to each tappet circuit (i.e. the circuits after the CPS valves). A continuous flow through the circuit ensures the necessary stable pressure differences required for a stable transfer between the small and large tappet (or vice versa).

NOTE:
In the event of a small lifting height, the tappet circuit, in principle, has no pressure when the CPS valves are open, which produces a return flow to the oil pan.
A filter is located in each passage.
The duct at the rear edge supplies the following components/functions with oil:
- The camshaft chain's hydraulic tensioner
- The VCT valve and the VCT unit for the intake camshaft
- The camshaft bearings for the intake camshaft (6, i.e. all except the front)
- The camshaft bearings for the exhaust camshaft (all 7)

Gear Housing
The drained oil from the camshaft chain housing is supplied to bearings and meshings, i.e. the oil is not pressurized. The oil is routed through the bottom of the gear housing via the rear bearing, onwards into the housing where the meshings and front bearing are spray lubricated.
The internal needle bearings between the shafts are also supplied by the oil on its way out from the camshaft chain housing. The oil reaches the bearings through the opening between the shafts.
Even the intermediate shaft bearings are lubricated by the oil that is sprayed around the housing.