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78 Mercury 40 hp 402 high idle

Burris

New member
Greetings, I have a 78 Mercury 402 that won't idle down for anything. New carb, stator, fuel pump, switchbox, water pump, terminals are good checked tdc and flywheel is correct. Ran well a week ago but hard to start. Found high voltage peak from brand new stator so was advised to change switchbox. Still wouldn't run for longer than 20 seconds. Found the kill wire orange, had 2 volts with key on. Disconnected it and it ran. Still hard start and idled at 1800. Checked timing again and it was retarded all of a sudden. Adjusted it back to the mark and still no change in rpms 1800 to 2000 . Whathrottle plate is closed. Can a trigger cause it to spark twice and speed the motor? It seems like I chased the timing mark one way then the other to no avail. And it got irratic in nature showing 2000 rpms but barely spinning 600 at a couple points. What do I do?
 
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