Este es el sistema de funcionamiento del tapon de refrigerante del Volvo 2030 (sacado del manual original de este motor Perkins Perama marinizado por volvo)
Radiator 103-06/103-09/10
A pressure type radiator cap is employed to
obtain higher cooling efficiency. When the
coolant pressure builds up to the range of 0.9
±0.15kg/cm2 (6.51b/ft to 10.81b/ft) excessive
pressure is relieved from the overflow pipe. (
shown by white arrow).
When coolant temperature falls coolant pressure
may become less than atmospheric pressure.
As this may fracture the radiator, the
vacuum relief valve opens at 0.04 to 0.05kg/cm2 (
2.9lb/ft to 3.6lb/ft) to protect the radiator. (black
arrow).
N.B. Perama M25/M30 pressure cap is 0.5kg/
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