no idle

[rusty hook]

I own since new a 1997 mercury 40hp, 2 cyl, 2 stroke tiller. The poor boat sat for 3 years as I worked but now as I'm trying to go back to commercial fishing, I have developed my first problem. A fuel hose rotted and clogged my carb. I replaced all fuel hoses from tank to motor, replaced squeezie bulb, emptied the fuel tank, replaced plugs, emptied water separater, replaced fuel filter and removed and cleaned and soaked and cleaned and sprayed and inspected and cleaned the carb. Stupid motor will not idle. I have played with the slow speed screw and the idle adjustment screw for hours and no improvement. Today I checked the plugs and the top one was shinny and new and the bottom was oily. What do I do next? Am about out of money so last option is a real mechanic.

 

[bullet 101]

Re: no idle

If your not getting fuel for the engine to idle the idle circuit in the carb is probably stopped up or the fuel pump may not be supplying enough fuel.

 

[Silvertip]

Re: no idle

A clean (as new) plug says that cylinder is not firing. Check for spark. You didn't mention if you actually fully disassembled the carbs to clean them. Simply spraying stuff into the intake only cleans the throttle bore. It's the internal passages that get clogged.

 

[rusty hook]

Re: no idle

Sorry guys, Not much to this carb so I felt comfortable disassembling it. One time I soaked in laquer thinner overnight. Took a thin piece of wire and went through all holes. Inspected with a magnifying glass slowly for hidden holes. Also forgot to mention that I rebuilt the fuel pump.
I never have thought of myself as mechanically inclined, how do I check for spark?
I believe this motor can smell my fear.

 

[rusty hook]

Re: no idle

I fixed it all by my self sort of.