Max123
Well-Known Member
I hear you, and understand the idea of 'baselining' a motor - especially so if buying something with unknown history. That said, in retrospect, I can see that my past practice my have been a bit of OCD overkill.
I used to replace the impeller on our inboard ski boat every year (the internet would lead you to believe that an impeller will mummify and turn to glass if left for more than a season out of water). Its just not true, and after a few years of pulling out pristine impellers, I've downgraded the practice to once every 3-4 years. Also, I can't count the number of times that I've actually caused problems by doing preventative maintenance (who hasn't stripped screws, or dropped a nut into the bowels of the bilge...). Sometimes less is more.
For something like an impeller - condition is best assessed based on performance. Start the motor - strong stream at the telltale is a good sign, and then watch your temp gauge to confirm the first time you take it on the water under load. If you don't trust that, buy a water pressure manifold gauge (I did this on my old DF40). The pressure gauge is nice because the impeller performance does degrade over time, and you can see it on the gauge to better assess when to replace (rather than just guessing). Its also nice, because you will know right away if you suck in a bunch of weeds, or a plastic bag blocks the water intake.
I used to replace the impeller on our inboard ski boat every year (the internet would lead you to believe that an impeller will mummify and turn to glass if left for more than a season out of water). Its just not true, and after a few years of pulling out pristine impellers, I've downgraded the practice to once every 3-4 years. Also, I can't count the number of times that I've actually caused problems by doing preventative maintenance (who hasn't stripped screws, or dropped a nut into the bowels of the bilge...). Sometimes less is more.
For something like an impeller - condition is best assessed based on performance. Start the motor - strong stream at the telltale is a good sign, and then watch your temp gauge to confirm the first time you take it on the water under load. If you don't trust that, buy a water pressure manifold gauge (I did this on my old DF40). The pressure gauge is nice because the impeller performance does degrade over time, and you can see it on the gauge to better assess when to replace (rather than just guessing). Its also nice, because you will know right away if you suck in a bunch of weeds, or a plastic bag blocks the water intake.