did you run the pump dry?
should always use muffs with the hose on full. also need to make sure you have the bottom pickup hole blocked if its an AQ drive.
I have the same issue. There's water exiting the drive. when hooked to a hose bib. If I start it still no water out the exhaust prop port area. after first time out after winterized it over heated. I've checked the hoses 3 times there right I think once they were crossed at the pump changed impeller bearing and seals thermostat and hosed to thermostat housing took housing soaked it in Miratec acid and water boiled it out and wire wheeled it clean. someone said exhaust flappers are stuck possibly. Some say dont replace them say say you need them?