Radiator Cap Description
A pressure-vent cap is used on the radiator. The cap contains a pressure valve (1) and ventilation valve (2).
The cap has its face marked 1.1, which means that its pressure valve opens at 1.1 kg/cm² (15.6 psi, 110 kPa).
[A]: At air bleed 3. From reservoir
[B]: At valves closed 4. To reservoir
[C]: At pressure relief 5. Pressure in radiator
[D]: At vacuum relief