I am looking for a great running engine to replace my 1971 mercruiser 140. The block and manifolds got cracked by previous owner not taking out and draining the cooling system. Was wondering what engine I can replace this one with. Can it be a newer engine? or does it have to be at the same year of my current engine? I am wanting to keep my current upper/lower units so that is why I am asking. Can I upgrade my horsepower to a little bit bigger motor say like the 165 hp motor ?
