1999 40 HP Johnson cold start problems

7936048

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I have a 1999 Johnson 40 HP electric start, dual carbs. It is very hard to start, particularly after a long period on non-use. I some cases, I will have to move the throttle to 1/2 - 3/4 to get enough fuel into the syatem to start. Once it starts, it runs fine all day. There is no choke lever on this model, just a "primer" when you push the ignition switch "in" while turning it to start. <br /><br />Thanks in advance.
 

angus63

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Re: 1999 40 HP Johnson cold start problems

Are you pumping the fuel bulb firm when cold?
 

7936048

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Re: 1999 40 HP Johnson cold start problems

I do pump the primer until it is firm. The mechanic at the dealer where I bought the boat mentioned some sort of valve or switch you could throw only when cold starting, but not when running. Could he be referring to moving the primer solenoid to manual start position?
 

angus63

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Re: 1999 40 HP Johnson cold start problems

I think so (red lever at shreader valve). Do you hear a click when key is pushed in?
 

Cricket Too

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Re: 1999 40 HP Johnson cold start problems

How long do you hold the key in before starting? If the motor sits for extended periods of time you may want to try turning the key on and then pushing the key in for 8 -10 seconds then turn the rest of the way to start while keeping it pushed in.
 

waterinthefuel

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Re: 1999 40 HP Johnson cold start problems

How come you should push in the key for 10 seconds prior to cranking? If it's not turning over no fuel is getting to the engine, right?
 

rickdb1boat

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Re: 1999 40 HP Johnson cold start problems

After you pump up the primer bulb, the system is under pressure. When you push the key to prime it, it shoots that pressurized fuel into the cylinders, giving the motor an advanced shot of fuel to start rich with. 5 sec is enough to deplete the built up pressure and prime the cylinders. Then start as normal..
 

7936048

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Re: 1999 40 HP Johnson cold start problems

Got the boat out of storage today. Tried starting with hard bulb & holidng primer switch in but boat would not start. Coughed a few times and would not start. I then moved the primer solenoid to manual, turned the key and the motor fired right up. Let it run 10 -15 minutes and then cool down for 30 minutes. Moved the primer solenoid back from manual to normal and the engine started and ran fine.<br /><br />Thanks for your help.
 

angus63

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Re: 1999 40 HP Johnson cold start problems

Tom<br />Once the engine starts, you should be able to put the primer valve back in the run position. If not, you may have carb issues. Do you hear the click of the solenoid when you push the key in? If not, pump the bulb,then place the red lever in the start position and crank until she fires, and then put the red lever back in the run position. Eventually you'll want to find out if it is the solenoid, wiring, or switch thats causing the problem.<br />Good Luck
 
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