Description

DESCRIPTION

The cooling system is of the sealed type with forced circulation by a centrifugal pump (1) operated by the crankshaft through a POLY-V belt.

A thermostatic valve (6) fitted on the rear of the engine keeps the engine temperature at an optimum level: it opens when the coolant reaches a temperature of 87 ±2°C.

The radiator (4) cools the fluid by dynamic air and by two fans with two speeds which are turned on by a thermal contact (5) located on the radiator; two additional resistances and a relay operate the higher fan speed if high temperatures are reached.

The expansion tank (3) tops up the circuit if the level falls and absorbs the changes in the volume of the coolant due to changes in temperature: it also vents air from the circuit.

The circuit also includes a coolant temperature gauge sender (8) and a thermal contact for the maximum temperature warning light which turns on when the coolant temperature exceeds 115 °C.

OPERATION OF THE CIRCUIT

After the fluid has cooled the engine it leaves the cylinder heads and reaches the thermostatic unit (9). From here, if the temperature is below 87 °C it is drawn into the pump (1) through a longitudinal coolant return manifold located between the two cylinder heads. Conversely, if the temperature exceeds this value, the fluid is directed to the radiator (4) through the opening in the thermostat, also heating the ignition coils through a special support.

After being cooled in the radiator, the fluid returns, still through the longitudinal manifold, to the pump which directs it to the engine.

A special union on the right-hand cylinder head receives the coolant from an additional groove on the head and sends it through two special pipes to the heater (10) of the climate control system and to the throttle body to warm it.

The latter is connected to the expansion tank (3) via a special pipe which in addition to returning the coolant fluid also vents air from the system.