1980 Evinrude 75 hp idle/run issues

thatone123

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Joined
Mar 7, 2009
Messages
707
This outboard has had problems with high idle in the past. I have tried to lower idle by adjusting the throttle cam, and cables and thought I had it solved, although it seems almost impossible to get a proper low idle. Outboard was put in a lake recently and it ran but when slowed down lost idle and died and hard to start. Does this seem like carb problems? or...?
 

flyingscott

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Apr 8, 2014
Messages
8,229
Why are you adjusting the cam? Have you done a link and sync? Is the roller on the carbs in good condition? what is compression? Do you have spark on all 3 cylinders? Does those carbs have low speed adjustments?
 

jimmbo

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May 24, 2004
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13,961
It sounded like the initial problem may have been a poorly adjusted throttle cable. However since you were turning screws, who knows what you've got.
Idle speed is set by retarding the Timing, the carbs are supposed to be fully closed at idle. As mentioned above, the sync between the carbs and Timing needs to be verified and corrected if need be.
When making any adjustments to the throttle linkages, it is best to unhook the control cable, as it will need its length adjusted, for proper preload after all is corrected
 

thatone123

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Mar 7, 2009
Messages
707
OK Guys - I am working on your solutions. Yes, it has good spark and compression about 110 or so. Runs good if it wants to, if that makes any sense. I am going toward the timing plate, link and sync and cable. Cable seemed screwie from the get go. I will let all know what happens. I think I cleaned the carbs a long time ago and the motor sat for the summer.
 
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