Mercury 65HP Hard Starting Problem

[baileybones]

Hi,

I have a 65HP 3 cylinder motor. The year is 1973-1975.

My problem is getting it to start. I choke it and give it throttle, but it just cranks and cranks. Will not start. But when I spray some
gas directly into the carburetors, it fires up right away. And once it's warm, it will start no problem. One crank and it starts.

Any ideas on what it might be? I'm pretty sure it's a carb problem or not drawing the gas into the carb problem, but don't know
what it might be exactly.

Thanks

 

[jbjennings]

Re: Mercury 65HP Hard Starting Problem

CHeck and see if your choke plates are all closing TOTALLY when pushing the electric choke switch. If they don't totally close, it will be hard to start. If not that, the fuel bowls may not be full due to incorrectly adjusted floats.
JBJ

 

[baileybones]

Re: Mercury 65HP Hard Starting Problem

Thanks. I'll check both of those things. Hopefully I can find the problem.

 

[GA_Boater]

Re: Mercury 65HP Hard Starting Problem

You didn't mention squeezing the bulb until it's firm in the starting procedure. Very hard to start if you don't.

 

[baileybones]

Re: Mercury 65HP Hard Starting Problem

Yes. I squeeze the bulb until it's firm before trying to start.

That's what I don't understand. How come if the bulb is firm, gas is not making it into the carbs.

 

[Silvertip]

Re: Mercury 65HP Hard Starting Problem

Yes. I squeeze the bulb until it's firm before trying to start.

That's what I don't understand. How come if the bulb is firm, gas is not making it into the carbs.

Fuel probably IS making it's way into the carbs and it must because the engine runs fine once started. The problem is that fuel must make it OUT of the carbs through the various passages and into the intake, then to the crankcase then through the ports to the combustion chamber. So fuel sitting in the carb bowl has only made it half way to the engine. Choking consists of closing off the throttle bore completely so the engine can drawn additional fuel into the intake. Make sure that system is working and that you actually HOLD the choke closed by pushing and holding the key in while cranking the engine.