CLNT TEMP Overheat after engine shutdown

Hi all,

I have recently observed that after shutting down the 915 in my plane on warm days at a coolant temp reading of about 113-115 degrees, the engine will keep heating up after shutdown and the coolant temp will reach values about 5-8 degrees above what it was upon shutting down. So, by chance, I noticed after restarting the avionics, that my engine reached a 122 degree water temp about 2 or 3 minutes after shutdown, which is 2 degrees above redline.

Is this normal behavior or should I make sure to sufficiently cool down the water temp before shutdown to around 110 in order to avoid an overtemp? In my installation, it is required to set RPM at around 3000 for enough airflow over the underbelly radiator to cool down the coolant temperature. However, that would then go against the 2 minute cooling down of the turbo at idle…

Any thoughts? Is an overtemp inspection required now?