1982 Johnson 25 idles high

imalunatwo

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I have a 1982 Johnson 25 that seems to idle high. I have rebuilt the carb and the fuel pump so I can rule them 2 out. It seems like when it is idling high, I can pull on what I believe is a retainer assembly that sticks out from under the fly wheel in a clockwise manner and the idle goes down. When I let go, it idles back up. I dont see any adjustments anywhere. The retainer is coneccted to a spring that goes to the control lever. Any ideas? I dont think it is my timing because the motor runs fine besides the high idle. Thanks for any and all help!!
 

Sir Robin

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Jun 29, 2010
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Re: 1982 Johnson 25 idles high

Outside the cowel, on the port side, there is a screw at the throtle gear.That is the idle screw. Turn in or out to raise or lower the idle. It is the throtle stop screw. The spring and assembly that you see is thetiming base, or stator that goes from aprox 12 deg. atdc, to aprox 30 btdc. Most of the 'throttle" is timing at slow speeds.
 

Sir Robin

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Re: 1982 Johnson 25 idles high

Is this a ''tiller" or remote motor?
 

imalunatwo

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Aug 12, 2010
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Re: 1982 Johnson 25 idles high

This is a tiller. The screw you are talking about on the outside under the cowl is already all the way out. I just got the boat and I dont have a manual yet. Is there any links where you can download the manual? Thanks
 

Sir Robin

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Re: 1982 Johnson 25 idles high

Perhaps the previous owner adjusted the max timing screw and also the advance link instead of the idle..... Sorry i dont have a picture for that. I am thinking that the carb should be checked that the throtle plate completly closes. Some times there is a tendancy to tape the throtle cam......Because it wears..... bhile says it right, a manual will get it right, though USUALLY the advance portion happens in the first 3/4 twist of the throttle. the last 1/4 finishes the throttle plate opening. Oh yea, DONT forget to check max timing. 34 deg, I think......NO MORE Do you have any pic's?
 
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imalunatwo

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Aug 12, 2010
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Re: 1982 Johnson 25 idles high

I did the link and sync, it seems to idle better now. I havent had it out on the water yet, but everything with the throttle seems alot better. It idles fine in a tank. I also found that I had a sheared fly wheel key. I think that had alot to do with it. Another question question, where is my timing mark pointer on a electric start? Is it on the starter?
 

Sir Robin

Petty Officer 2nd Class
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Jun 29, 2010
Messages
126
Re: 1982 Johnson 25 idles high

Shearing key is a bummer, as shaft damage is a given. Did you LIGHTLY sand shaft and flywheel with #600 wet/dry sandpaper? Snapping key will gall shaft & flywheel not permitting proper torque, speaking of which, what did you torque the nut to? Just "tight" , and the key will snap again
 

imalunatwo

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Joined
Aug 12, 2010
Messages
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Re: 1982 Johnson 25 idles high

I torqued the nut to 120 psi. Motor seems to run great now. [ knock on wood]
 
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