Technical Thermostat cover

[JonPiz]

I drove the car properly for the first time since the rebuild. The flap activated by the thermostat opened however it hasn’t closed again, even by the next day. Is it a be problem just leaving this open rather than replace the thermostat?

 

[Piet59]

Hi JonPiz, don’t know if you already have the answer, after almost a year. In theory the flap must close in the end when temperature drops to cold. However I have seen many flaps that remain open for about one cm with cold engine. This means that with low outside temperature it will take longer for the engine to reach its operational temperature and when you often do so this means extra weer of the engine, that should be avonden of course. I discussed this matter last saturday with a Fiat 500 technician at the annual Fiat 500 fair in Badhoevedorp. He told me that a not fully closed flap when engine is cold is no problem since most Fiat 500 owners do not drive their 500 in winter. Most important is that the flap is fully open when engine is at operational temperature. Also important is that one regularly controls the position of the flap with cold engine and with hot engine.
Kind regards, Piet