1978 115 HP Mercury will not restart after warmed up

1978 115 HP Mercury, ran around lake for awhile but then would not restart. This has happened every time I have taken it out. Seems like years ago had similar problem and replaced rectifier.

Could that be the problem again or what? People I know just look at me and kinda shake their heads...

I know next to nothing about engines...hope you can help.
Thanks, Charlie

Re: 1978 115 HP Mercury will not restart after warmed up

There are lots of possibilities. Your best bet is to do some basic troubleshooting to narrow down the problem. Here are some suggestions:

1) Use a spark tester to see if the spark has failed when the motor does not want to start.

2) Squeeze the fuel bulb before cranking to see if it is soft or if this helps the motor to start.

3) Spray some fuel mix (50:1) into the carb throats and crank the motor to see if this affects how the motor starts.

4) Observe if the motor smokes a lot when it finally starts.

After reporting back on what you find out, you will have narrowed down the possibilities and will likely get more useful suggestions on what to do next.

Re: 1978 115 HP Mercury will not restart after warmed up

Was there water coming out the pee hole when it was running?

Re: 1978 115 HP Mercury will not restart after warmed up

hkeiner has it right do the troubleshooting first that he listed - nobody can just say it's this or that without some kind of testing and identifying symptoms - post back any info ie: does it start after cooling down , does it just cut out completely without warning etc.