12
400 Series
To test and to inspect
Operation 12-6
Visually inspect for damage, renew the thermostat if the valve is open at ambient temperature. 1 Put the thermostat into the water. 2 Raise the temperature of the water gradually. 3 Record the valve opening temperature and the valve lift. Engine
Temperature when thermostat valve starts to open °C (°F)
Temperature when thermostat valve fully open °C (°F)
403C-11
75 (167)
87 (189)
403C-15 404C-22
80 to 84 (176 to 183.2)
95 (203)
404C-22T
71 (159.8)
82 (179.6)
Notes: l The start to open temperature is stamped on the thermostat l 3 to 5 minutes will be required before the valve starts to operate.
H1107
96
Workshop Manual, TPD 1458E, issue 3 - Perkins Confidential: Green
