Lubricating System (Turbocharger (TC))

Lubricating system




1. Oil pump
2. Relief valve
3. Oil thermostat
4. Piston cooling nozzle
5. Spring loaded piston type valve
6. Compressor shaft
7. Drilled oil way from the main oil way
The high power output has placed greater demands on the engine lubricating system and cooling. The following have been changed in comparison to the other 5-cylinder engines:
- The oil pump (1) capacity has been increased by a wider pump wheel and a modified profile.
- The relief valve (2) has a more rigid spring and opens at 6 bars of pressure (B5254's opens at 5 bar).
- An oil thermostat (3) regulates the flow of oil to the oil cooler. The oil thermostat begins to open at approximately 95°C and is fully open at an oil temperature of approximately 150°C.
- The piston cooling nozzle (4) brings oil to the underside of the pistons. The oil is supplied to the nozzles from the main bearing oil supply ducts and flows through spring loaded valves (5) which open at 2 bars of oil pressure to preserve good oil pressure at low engine speed (RPM) when piston cooling is not necessary. A common ball valve is used for cylinders 2-3, and 4-5 while cylinder 1 has its own valve.
- Compressor shaft (6) lubrication oil is supplied via a drilled oil way (7) from the main oil way in the block. The return pipe is connected to the sump.

Oil capacity
Replacing oil and filter : 5.3 liters

Dry engine, after reconditioning: 6.2 liters (applies if the oil cooler is drained which contains approximately 0.9 liters).