Re: 28' Marinette (Aluminum) - Restoration
You are indeed a brave man. The hull is one thing, but having to address two engines and transmissions is another issue.
We still see some Marinettes on the Tennessee River, as aluminum boats last just about forever in fresh water. Unfortunately, any aluminum boat kept in salt water has to be properly painted and protected with anodes.
One great thing about stripping an aluminum boat is that you don't have to rush and prime it--as they're not going to rust. And hopefully there are experts available to advise you on refurbishing the hull and patching the bad places. I hope you have a qualified welder that can TIG weld any patches.
FYI: NAPA also has a great acid based metal cleaner that is sprayed on with a yard sprayer, and rinsed with water after 5 minutes. All the pontoon boat owners use the stuff. There are also other aluminum cleaners available at boat yards.
The 318 straight inboards were in many of the houseboats built in the 1980's. I would think you could find some marine salvage yards with fresh water 318's that are rebuildable. Many of the houseboats were built in Tennessee and Kentucky, and that would be a good place to look for salvage engines. While you're at it, you also want the tranny's to be at 100%.
It would be so much easier if you stuck to 318's. If you had to change brands, you'd do best to buy a whole donor boat with a matching pair of inboards and switch the motors over. Other options would be to switchover to inboard outboards or reinforce the rear end and switch to a pair of big 4 stroke outboards on aluminum external motor mounts.
Remember that any wood that needs replaced needs to be nothing but marine plywood. After all of your hard work, I hope you have a way to get this boat out of the water--if it's to remain in salt water.
