Lubrication system

LUBRICATION SYSTEM

1. Oil pump with suction device
2. Oil sump
3. Oil radiator
4. Thermostatic valve
5. Oil filter support
6. Oil pressure limiting valve
7. Oil filter
8. By-pass valve
9. Engine oil minimum pressure warning light sensor
10. Spray jets

The engine lubrication system is pressurised through a rotary gear pump (1) complete with suction device fastened below the two main bearing caps.

The pump is operated through a "silent" chain drive which transmits motion from the crankshaft to the pump spindle.

A limiting valve (6) controls the system pressure. During intake, the oil is filtered through a net filtering element on the intake and then crosses a replaceable filtering element on the supply line.

A longitudinal oil groove in the crankcase allows lubrication of the crankshaft, pistons and connecting rods. Two other grooves allow lubrication of the cylinder heads and then all the components of the timing system including the hydraulic tappets. A recirculation system and a vapour separator recover the oil vapours leading from the right cylinder head.

On the oil filter support (5) there is an engine oil minimum pressure sensor (9) which is connected to a warning light on the instrument cluster to alert the driver if the oil pressure is too low.

The oil filler plug is located on the timing gear cover of the left cylinder head.

The lubrication system includes an engine oil cooling radiator (3) and a thermostatic valve (4) located in the oil filter support. With temperatures below 82 ± 2°C, the oil flows directly into the cartridge filter and returns to the engine, with temperature above this value, the thermostatic valve is open and allows the oil to flow into the cooling radiator to lower the temperature.

To improve cooling the piston skirts the crankcase has spray jets (10) with a small valve incorporated which opens at a pressure of 2.25 ÷ 2.75 bar.