Using Automotive replacement parts

When I got this boat I went over it fairly thoroughly. I marinized the automotive carb, replaced the automotive fuel pump....still need to swap alternators. I even scratched and sniffed the freeze plugs in the block to make sure they were marine. It has run quite well until today. The last skier of the day told me that every time he was pulled he noticed the bilge pump was running. I shut down the boat and checked the obvious, rudder port and prop shaft and found no leaks. I started the engine and checked hoses and raw pump and then saw the leak coming from behind the circulating pump. After dropping off all the others I went back to the marina and pulled the pump off. As I expected there was a regular tin cover on the back with pinholes from rust, and a steel impeller. Who would expect less after seeing the carb and pump. I should have guessed it. Just a note to any of you who may not know, though it seems most of you here do, there is a good reason why marine engines require marine parts, safety and reliability. Do yourselves and the next owner a favor and don't skimp on the parts. Another little noticed thing is the rear cam plug. I've seen several engine leaks caused by corroded cam plugs, the only plugs that even many marine rebuilders don't replace with brass for some reason. Unfortunately you don't see THAT plug without pulling off the trans and housing. Just my 2cents for the day. Happy skiing...we're in full swing here now until October or so.
Ken