2007 SV211 occasional overheat issue

[tenfive67]

Ok guys/girls, looking for suggestions on where to start. zr6 with closed loop cooling. From time to time, not always the same situations the engine will overheat. it has a strainer and it has been checked, not much in it but cleaned anyway, no gasket in place so I installed one off my 80SN. Still having issues. Checked inlet valve at bottom of boat. Ive been through many issues with the 1980 but it is not a closed loop system, mostly impellers over the 30 or so years we have had it.

The 07 has probably done it 4-5 times, never gets that hot just hot enough to set off the alarm (200 or less). Sometimes we take it out all day and it runs 165-175 without any issues then days like today we were out for 45 minutes and it did it, let it cool and got back to the dock. Went out later and did fine for an hour or so before acting up again. I haven't put my infrared temp sensor on the motor when it says hot so I haven't ruled out the sender yet.

Has anyone else had issues like this with theirs and if so please share.

Thanks in advance for any input!

[HS]

Never had it happen with my old zr 6 but a thing to check is the fresh water flush fitting cap and gasket. When's the last time the impeller was changed?

[tenfive67]

Ive checked it in the past but i will again. Don't know when the impeller was serviced, purchased the boat about a year ago used. After sleeping on it im wondering if it might be a thermostat? Trying to think of something that would be intermittent and not happen every time the boat goes out. Guess ill start at the lake water pickup and work my way up from there. Thanks for the advice.