I have a 1990 Alpha one Gen 1 with raw water pump in the leg. I had this boat for 2 seasons. So last winter I bought all new parts for it. I didnt replace the pump this spring but did my thermostat. My boat ran 145F all of last summer. After replacing thermostat it ran about 150F? Kind of weird unless new thermostat was just a little different. I did get the 143 F thermostat. No overheating or anything like that last 2 seasons.
Anyway so I serviced my drive today. I took everything apart and noticed the white water tube was melted like a mushroom. Everything else looked good. Impeller was little worn but not bad. Pump housing was decent and not melted. I replaced everything and checked it on the hose.
My question is why was the plastic tube melted. Is this normal?
I ran the boat for 2 seasons and never checked the pump. I also dont know the last time it was replaced. So does this happen over time. The big copper pipe was in good shape. Just the plastic one was melted on the top half. Also why did I get little variation in the temp after replacing the thermostat or was this because of a wearing pump.