Hi all, I’m having an issue with my new to me 2004 optimax 115. S/N 0T845869. The motor has about 130hrs on it and has a new impeller. At idle (in water) water pressure is between 1 and 2 psi and temp runs between 130 and 145 (bounces around a little assuming due to the thermostat opening). On plane pressure is around 12-14 psi and temp is 110 or so. I can run on plane or idle all day with no issue but… if I’m on plane running for a few minutes then back off of the throttle to I guess around 2000-2500rpm, pressure drops to around 8 psi but temp immediately spikes to 180 and I alarm. I wait for it to cool a little and it fires up and temps stabilize again. It’s EVERY time I come off of plane. Ordering a thermostat and gasket today but I’m not convinced that’s the problem. ANY input would be appreciated.