1997 Johnson 15 hp

Well I just recently bought a 14' Klamath Deluxe S last week. I was able to take it for a few test drives before purchasing the boat and motor. The first time didn't go as planned because the engine didn't want to idle at all. The owner had the carb flushed and then I was able to take her out once again. This time the motor had a rough time idling when cold and after running for a little while, she was idling like it was nothing. I was then sold on the boat. Brought the boat home and fixed the kill switch. The kill switch was not grounded anywhere so I ran it to the negative connection for the starter cables as shown. I was wondering if this is an ok ground for the kill switch/button. Now the next issue, the motor does not seem to idle running on ear muffs. As long as I have the throttle above the dot on the tiller for starting she will run. As soon as I let go of the throttle, she will die at idle. This is all in neutral of course. Was wondering if anyone has any suggestions as what might cause this. Hoping to take the boat to the river tomorrow and run the motor in gear for awhile and see if she will idle then. Sorry for the long paragraph. Thanks ahead of time for any input!

shane.b.stanley said:

Well I just recently bought a 14' Klamath Deluxe S last week. I was able to take it for a few test drives before purchasing the boat and motor. The first time didn't go as planned because the engine didn't want to idle at all. The owner had the carb flushed and then I was able to take her out once again. This time the motor had a rough time idling when cold and after running for a little while, she was idling like it was nothing. I was then sold on the boat. Brought the boat home and fixed the kill switch. The kill switch was not grounded anywhere so I ran it to the negative connection for the starter cables as shown. I was wondering if this is an ok ground for the kill switch/button. Now the next issue, the motor does not seem to idle running on ear muffs. As long as I have the throttle above the dot on the tiller for starting she will run. As soon as I let go of the throttle, she will die at idle. This is all in neutral of course. Was wondering if anyone has any suggestions as what might cause this. Hoping to take the boat to the river tomorrow and run the motor in gear for awhile and see if she will idle then. Sorry for the long paragraph. Thanks ahead of time for any input!

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Shane,
what is a carb flush? I'm guessing the carb needs a proper cleaning and rebuild. You can try adjusting the slow speed needle and see if that helps. Good luck.

Well based on the receipt I was given after the motor was worked on, it said they disassembled the carb and flushed it. I believe they cleaned the Jets and what not by doing so. Previous owner said that he had the carb rebuilt this year. I believe the main problem is the carb due to the motor not being used very often. I shall try tinkering with the idle adjustment speed needle this afternoon. Thanks!

shane.b.stanley said:

Well based on the receipt I was given after the motor was worked on, it said they disassembled the carb and flushed it. I believe they cleaned the Jets and what not by doing so. Previous owner said that he had the carb rebuilt this year. I believe the main problem is the carb due to the motor not being used very often. I shall try tinkering with the idle adjustment speed needle this afternoon. Thanks!

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OK. Hopefully it just needs to be dialed in. I forgot to ask, is the dot on the tiller the shift position? I assume its idling too fast to shift gracefully into gear?
Keep us posted.

I do believe the dot is where you are supposed to shift and that is also where it should be able to idle. Took it out today, played around with the very end of the tiller, did notice it slightly move the throttle cable when it is all the way out, (as I turn one way the end of the tiller goes in). In order to keep the motor running, I have to have it above where the shift dot is. If I go down to the shift dot and then shift it into gear, it dies. Came home and found the idle adjustment screw and started adjusting that, seems I can only get it to idle with the screw all the way in (as far as it can keep the throttle open) and to me that seems too high of an idle compared to my older evinrude 6hp. Maybe it does need to idle that high?
Maybe this extra information could help. Once it dies, I have to pull out the choke to restart it. I'm thinking I should replace the spark plugs. Hope to maybe do that tomorrow morning!

If you need to choke it to re-start it, the low speed possibly needs adjustment. If that doesn't help, I would look in the carb myself to see what exactly has been done.

Here are the spark plugs I took out. So now as to adjusting the low speed, where do I look to adjust the low speed?

sounds like an air leak.

$.02

So if it so happens to be an air leak, how would I test for an air leak?

On your engine you have both an idle RPM adjustment knob and an idle mixture adjustment.
Would suggest at this point that you familiarize yourself with the placement of these and use them!
You cannot hurt your engine by making adjustments of the idle system as long as you know where you started from.
Do you have an owners manual?
I do not believe you have an air leak anywhere.

So I have gotten the motor to idle like it is supposed to, I adjusted the idle mixture screw on the carb. I do not have an owners manual (probably should grab one) thanks everyone for your help!

Good deal, Pappy is mountains more knowledgeable than me about these things so....

shane.b.stanley said:

So I have gotten the motor to idle like it is supposed to, I adjusted the idle mixture screw on the carb. I do not have an owners manual (probably should grab one) thanks everyone for your help!

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Great! Enjoy your motor. =D>

Thank you!