I have moved your post under the first thread you started last week. There is no need to start another thread each time you have a question. More importantly, you will get a better response by staying within the same thread, as others people who have posted within the thread will be automatically notified of your new post.
You are asking the fuel consumption of a boat that had two different motors in years 1998 to 2002 (Cats & Detroits) and then another brand of motor in the years that followed (Cummins). Unless you can be more specific in your questions, you may not find the answers you seek.