Originally Posted by russiarulez
What else is required to convert a 40 hp to a 50?
I looked into this myself and gave up because a set of 50 carbs are like hen's teeth! As far as I know the 50hp shares exactly the same block as the 40hp, however there's a larger diameter exhaust manifold, and of course the carbs are different too. No doubt the throttle and idle adjustment will all need to be tinkered with after swapping over. Still probably easier buying a Yamaha 50G outboard. The 40V ones are still desirable and should fetch a reasonable price if well-maintained. There's also the propeller. The stock 6H4 40hp uses a aluminium 10 5/8 x 12" pitch. Pretty sure the 50hp takes a 13" pitch.