The thermostat is located in the inlet fitting of the cooling system, that is, before removing the thermostat, the coolant must be drained to a height below the fitting. The thermostat is checked in the same way as on a gasoline engine. The thermostat release temperature is 80-82°C and at a temperature of 95°C the thermostat should open completely. In this case, the pin should protrude 8 mm from the thermostat.