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79 140HP Johnson idle adjustment question

V

Vinh

Regular Contributor
Hi,
My friend has a 79 140HP Johnson with a bad joke selenoid (removed). The engine starts up fine but the idle is like 4K RPM. I can't seem to find the idle mixture screw any where on the carbs? Any help would be greatly appreciated.
Vinh
 
There are no idle mixture screws on those carburetors.-------------Need to adjust the throttle cable to pull the arm back to idle position.
 
Racerone,
Thanks for the info. I adjust the cable all the way back and it still idle very high. I thought the choke selenoid needs to be hooked up to help control the air a little. So I bought the choke selenoid and hooked it back up. It still idles high but now when I put it in gear and raise the RPM the choke selenoid is closing the flapper door and caused the motor to shut off. Can you give me some info on how the selenoid control by the stator current? Is my timing off? Is there a way to adjust the timing on these old motors? THanks
 
You are way way off in your thinking. You better get a factory manual.

1. Choke solenoid is not controlled by anything except the key. Push key in, choke closes, let key out, choke opens fully.
2. All throttle butterflies must be fully closed at idle. You DO NOT "prop open" the butterflies to adjust idle.
3. Idle speed is controlled by timing.

You need to do a proper link and sync, and all that is covered in the factory service manual.
 
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