My buddy has a mid 60's 413 in a boat that he is restoring, and wants me to take care of the engine for him. So the engine has 186 hrs on it, and with that few hours I would think it would not need a whole lot of work besides seals and looking everything over, plus valve springs, maybe lifters. It appears really clean and has been stored inside, the guy removed the motor from the boat in the 80's and never did anything else to it. What does everyone think? does this sound like the best approach? My buddy bought it from the original owner who claims nothing is wrong with the motor, but I would think the seals have dried out to the point that it will be a leaker

thanks
scott

Don't be surprised if it is completely whipped. Most boat owners take the approach of if it starts it doesn't need anything. Maintenance is usually close to nonexistent. Compression test and a leak down test will tell the tale. Check the exhaust ports for signs of water leaking into them from leaking exhaust manifolds. Marine manifolds are water cooled and if they leak they can literally fill the engine with water.

Kevin

Thanks for the input. From what i can tell this was pampered from day one, and has not been in use since the 80's. I think it should be straight forward, but I will closely look at the manifolds and valves as I know what a problem they can be. I think you are right I should do a leak down test before anything.

thanks
scott

The thing about a marine application is the engine is loaded hard the whole time it is in use.. An automotive engine pushing a car at highway speed typically uses less than 20hp.. Depending on hull design & weight a boat running 40 mph takes over 100hp

A couple areas that really are gonna need attention, first the valves & seats because there is no lead in fuel these days & in a marine application the seats get hammered..Second as old as the bearings are & as hard as they get used it's quite likely they will flake apart if put back into service... The rings may be ok but you need to decide what your comfortable with...