TOPIC: 1961 40hp Lark 3 fuel leaking

I am pretty sure I know the answer to this but I just need to verify with someone. I got this engine last year for free. I am new to working on motors. I pumped fuel into it today. When I crank the engine fuel seeps out around the lower unit. I pulled the lower unit and when I look up the shaft it is coated with fuel. I can see a hole and see the cylinder head moving back and forth. I am assuming that the cylinder wall has corroded and blown out and the power head is toast.

Well, I think I may have answered my own question. After finding an image online of the bottom of the 63 version of the powerhead, my guess is that I am looking at the exhaust port for the lower cylinder. Since the fuel is not currently burning off it is just draining dutifully out the port as more fuel gets pumped in. Am I correct? If anyone is following thanks for listening to a rambling first timer trying to bring an old engine back to life.

I would bet that the fuel pump diaphragm is deteriorated and ruptured. This allows a massive leak of fuel into the cylinder and then out the bottom.

Here's the repair kit for that:

www.marineengine.com/newparts/part_details.php?pnum=SIE18-7801

And here is a 1961 40 hp fuel pump diagram. IDK which model you have, but the fuel pumps would be the same across the various models for 1960. You can find your engine's model $ on the metal plate riveted to the transom bracket.

www.marineengine.com/parts/johnson-evinrude-parts.php?year=1961&hp=40&model=35524&manufacturer=Evinrude§ion=FUEL+PUMP

When you pull apart the pump, be aware that there are a couple of springs and little metal or plastic discs within, be prepared to catch them when you open it up.

HTH & G'luck with the troubleshooting. Let us know if the diaphragm is the problem; if not, we can troubleshoot further...ed