Just did a sea trial on a 380 - please advise

[Southpaw II]

From what I understand, the hour meters don't contain any numbers. They simply read the information from the engine's computers to display engine hours. Your hours displayed on the dash should be correct. That being said, the proper 8.1 diagnostic tool can provide loads of information that will let you know more about the usage of the boat such as percentage of use at various RPM levels. A boat with 90% of it's running time at full throttle might be one on which to pass! (although at the cost of fuel, that is unlikely).

You might be able to test the manifolds with a magnet. If I recall from my high school days, magnets won't be attracted to aluminum, but they sure will to cast iron. The risers are stainless steel. In a salt water environment you don't want to take a chance with these components. If they fail on the inside where it's undetectable, it could cost you a new engine! The manifolds have an approximate lifespan of 5 yrs with salt water use. How will you know their age and condition??

Actually, my tachs display "boat" hours. When we hook the diagostic computer to my ehgines, it show about 150 hours less than the tach display. Your results may differ.......

Don