Hello. We have a 01 Outback V. The engine was rebuilt a couple seasons ago and has been running weird since. Since the boat was rebuilt the engine temp will go up to about 190-200 and them go down to 155ish. It does this pretty rapidly and we have tried to replace the thermostat with an automotive and a marine thermostat. If we take the thermostat out and run the boat the boat will stay steady at a 145ish temp and never climb. Is this something that anyone has seen? We are working on trying to figure it out.

Thank you!!