still won't idle

[tomko]

I have a 1982 mercury 40 hp outboard that won't idle. So far I changed the spark plugs,changed the gas twice,cleaned the carb twice,changed the needle and seat,and tried a different fuel line and primer bulb,none of these things made any difference.I adjusted the screws for the idle and nothing changed.I checked the control cable and it seemed okay. There is a little bit of play in it, but when I move it to take the play out it doesn't make any difference. If I push the cold start button on my control and give it throttle it starts but when I pull the control to neutral it quits.I don't know what to try next. Thanks.

 

[lonewolf5347]

Re: still won't idle

HAVE YOU CHECK THE SPARK TO SEE IF CYLINDERS ARE FIREING?

 

[Chris Wilson]

Re: still won't idle

This is a longshot but it worked for me on my Evinrude. I think it might apply to any 2 cycle.<br /><br />We had poor idle and poor power on the low end. It also ran a little erratic at times even at higher speeds, nothing bad - just not right.<br /><br />To make a long story short, we found out the thermostat was stuck open and was over cooling the engine. If the engine does not get up to temperature it will not run correctly.<br /><br />We changed the thermostat for a new one and the improvement was dramatic. We could not beleive it was the same engine. The manual we were checking mentioned some tests to verify the operating temperature. We initially skimmed over that section since we "assumed" that they were worried about the engine being too hot, which of course they were. However, they also noted that there was a test to see if the engine was too cool. Once we paid a little more attention to what they were implying, we figured it out.<br /><br />Don't know if Mercury would behave the same under over cooling conditions, but it might be an easy thing to check.<br /><br />good luck...