Bad Cold Starting on 40 HP Mercury

I have a 1981 40 HP mercury that is very difficult to start on the first start. I often have to use starting fluid, and it then does well. After the first start, it cranks fine. The carbs have been rebuilt and new plugs. Thanks for any thoughts you have.

Re: Bad Cold Starting on 40 HP Mercury

Are you getting a strong spark?<br />I would not use starting fluid, try a few squirts of premix gas instead.

Re: Bad Cold Starting on 40 HP Mercury

i had a 15 evinrude that did same thing. turned out the lower crankl seal was bad, allowing compression past it and not enough power to START, but once started, it was easy all day<br /><br />yes, dont use starting fluid in a two stroke, EVER EVER EVER EVER EVER EVER.<br /><br />ps, i have that same exact motor, year,hp etc, but mine is electric start

Re: Bad Cold Starting on 40 HP Mercury

Try this: turn key on but don't start, push key in and count to 10 slowly, then start the motor. This gives the enrichner time to prime all the cylinders. Don't worry about flooding it. Its almost impossible to flood those old Mercs when they are cold.

Re: Bad Cold Starting on 40 HP Mercury

Holding the choke on for 10 seconds will do nothing - that motor doesn't have an "enrichener" system, rather it uses a traditional choke flapper over the mouth of the carb. Often, these flappers can wear on the pivot shaft to the point where they won't properly close off the carb face.<br /><br />Here's a test for you... Next time to go to cold start it, stuff a rag in the carb mouth. DO NOT push the choke button on the controller! Otherwise, try starting the motor as you would normally. If the motor kicks right off, then you know you've got a problem with the choke. Have someone operate the choke button while you watch how far it travels and whether it completely closes off the carb mouth. If there's an airgap between the flapper and the mouth, it may not be getting enough of a choke effect. Lots of those older Mercs are cold blooded and need a full choke....<br /><br />- Scott

Re: Bad Cold Starting on 40 HP Mercury

Priming the bulb until firm????