I have had this problem since I bought the motor in 1977. It had only about 10 hours on it. The motor runs flawlessly under all conditions. Starts on the second pull after winter storage etc. I have (way in the past tried to fix this for 10 years plus by doing all the obvious) including talking to every Merc tech at every marina or dealer I ever pulled into. (Float settings needle valves, compression tests, hose inspection replacement, different fuel tanks etc etc . How it works, Go out on a lake, run it all day or for a short while, if you sit for say less than about an hour it restarts first pull. You sit for longer than that and it will not start all day no matter what you do unless you slowly keep squeezing the primer bulb till it spills gas out the carb. You do that and first pull it starts right up.
I have not used this motor in ten years and will be bringing it out this fall for one more try to see if I can stumble on the cause and use it next year. Would like to get it running well and then save up for a newer motor and keep it as a backup, if not i will sell or keep if for parts.
I must be missing something, simple or small, like a hairline scratch in an o ring or a warm headgasket leak that allows fuel pressure leak and replacing it with an air block.
Any input will be appreciated.
I have not used this motor in ten years and will be bringing it out this fall for one more try to see if I can stumble on the cause and use it next year. Would like to get it running well and then save up for a newer motor and keep it as a backup, if not i will sell or keep if for parts.
I must be missing something, simple or small, like a hairline scratch in an o ring or a warm headgasket leak that allows fuel pressure leak and replacing it with an air block.
Any input will be appreciated.