Ventilation of Cooling System
The cooling system of the Z 20 NET DOHC Turbo petrol engine has additionally been fitted with a ventilation valve in the coolant return pipe. This is intended to prevent the formation of air cushions in the upward-facing part of the coolant return pipe.
The ventilation valve must be opened each time the system is ventilated. Only in this way is it possible to achieve optimum ventilation of the system.
Thermostat Housing
When compared to the thermostat housing of the DOHC Z 22 SE petrol engine, the thermostat housing of the Z 20 NET DOHC Turbo petrol engine has been fitted with an additional coolant connection to the coolant line of the turbocharger.
The thermostat housing of the Z 20 NET DOHC Turbo petrol engine is made of high-quality plastic and possess two additional connections that enable a feed to the driveside oil cooler.
| 1 | Engine coolant input | 6 | Additional heating connection |
|---|---|---|---|
| 2 | Engine coolant feed connection | 7 | Turbo charger coolant return connection |
| 3 | Engine coolant return connection | 8 | Heating return connection |
| 4 | Heating feed connection | 9 | Coolant compensator reservoir return pipe connection |
| 5 | Coolant pipe |