Re: How Much water?
The life of a rubber impeller is only about 4 years and most iboaters will advise changing it every second season.<br />The reasons are that it becomes brittle and breaks up leaving bits of rubber in the cooling system and removal of the Lower unit is necessary every few seasons to ensure it does not corrode to the crankshaft. If it's been there for 8 years, change it now. If the water is uncomfortable to touch., it's too hot and is not getting to the top cylinder and will cook your motor.