Re: Old boats and new gas
garyq - you can run whatever gas you want of course and put whatever additives you want as well. Totally up to you. But consider this:
If you have your original engine from 1965, then it is now 45 plus years old. Unleaded fuel has been the only choice for all practical purposes for around 35 of those 45 years. From your question, I assume you are a fairly new owner of this boat. While it is possible, I seriously doubt the previous owner(s) spent the extra money to put lead additives in every time they filled the boat with gas.
Regarding the octane, contrary to what many believe, as an engine ages and loses compression, its need for octane declines. Run a tank of regular unleaded and see how it runs. If it runs well, as I suspect it will, then continue to use it. There is absolutely no benefit to running a higher octane fuel than is needed.
My personal experience? I've owned the car in my avatar, a 1956 Chevy, since my high school days. (1976 for those interested
). Back when unleaded fuel first came out there was much hand wringing about the damage to the valve seats, etc. It turned out to be "much ado about nothing."
