FordGuy100
Registered User
Thats HP measured at the crank, which would be around 200hp at the wheels...which guys have done with just turbo IDI's and good (stock), turned up fuel systems.
My experience has been that different marine engines are set up differently, depending on the application and how the designer felt like doing it Most trailerable boats with gasoline engines I've worked on pulled in seawater and ran it directly through the block, as you described (and you're supposed to flush them out with a garden hose afterwards, especially if running in salt water). However, even on a trailerable boat, every diesel boat I've seen had water-to-water heat exchangers, so seawater came in and cooled off the pressurized antifreeze that actually went into the engine block. On that setup, you have two water pumps...the fresh water pump which is similar to a "normal" water pump i.e. what we have on our trucks, and a raw water pump with a rubber impeller like you described.I Know every situation is different but I've changed two water pumps on houseboat 454 gas engines and each of those had Rubber Impellers and constantly ran Lake water through Them. I guess the only thing that kept rust from building up inside it was the constant supply of new water.