If you are going to repower, figure out the how much gas you use per
year and multiply by what you pay to get an approximate annual fuel
bill. (You may not want to know this number.) Subtract the cost of
diesel times how much diesel you would burn to cover the same distance
to get annual fuel savings. How many years will it take to make up the
difference in the cost of repowering?

You should also consider the range issue and the fact that a new diesel
may outlast the new gas engine. For me to repower my 1987 26' cruiser in
gas might run $5000; diesel would be close to $20,000 since I also have
to change motor mounts, fuel systems, add insulation and more. I might
save about $1000 annually, figuring 150 hours of operation, the
different fuel consumption, and different fuel costs.

I'd be crazy to do this in a 17 year old boat, but I just might....

Capt. Jeff