'73 Evin. 6hp, Quit, Won't Restart

[Cabinupnorth]

I have a 73 6hp Fisherman twin, unit ran like a champ until one day was heading out onto lake and it suddenly lost power, and came to a stop, will not restart, occasionally will barely start and pops from carb. Has spark, getting fuel, cold compression (after several pulls) seems low @70psi (both cyls), pulls over seemingly easy. Could this possibly be a reed valve or crank seal issue? Seems strange to me that both cyls would have equal (seemingly low) compression, and have piston problems. I bought this motor last year, I don't think it has many hours on it, as starter rope has barely any wear and everything looks like new. I'm a mechanic, but not an outboard mechanic! Need input!

 

[JB]

Re: '73 Evin. 6hp, Quit, Won't Restart

Ahoy, Cabin. . .<br /><br />Pops through carb, huh?<br /><br />Have you verified spark on both plugs?<br /><br />Have you tried spraying fuel mix into the carb?<br /><br />If it has spark and wont start on sprayed fuel, #1 suspect: sheared flywheel key. #2, Reed plate failure.<br /><br />Let us know what you find.

 

[Cabinupnorth]

Re: '73 Evin. 6hp, Quit, Won't Restart

JB, Thanks for your speedy response, made much sense. After finding flywheel key intact, ended up bringing piston to TDC and holding flywheel while using my leakdown tester turned way down with both plugs removed and found air coming out opposite cyl. Pulled head and found gskt blown between cyls (very small area). Thanks Again!