This is a true as it gets. I have been doing this since I was a little kid. I used to spend every minute I could helping my dad assemble engines for our hydroplane. I have done this for a living for over 25 years, both on my own and for someone else. It has ALL been with marine engines. I have had my hands in a countless # of engines and I still learn new things on a regular basis.....and I do this every day of every week.