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1979 Evinrude 100hp timing

The timing is " fixed " for the life of the motor.---It normally needs no adjustment.----A sheared flywheel is one thing that throws timing off.---You can not find a sheared key with a timing light.----What is the motor doing / not doing ?---Have you done a compression test ?
 
racerone said:
The timing is " fixed " for the life of the motor.---It normally needs no adjustment.----A sheared flywheel is one thing that throws timing off.---You can not find a sheared key with a timing light.----What is the motor doing / not doing ?---Have you done a compression test ?
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"Fixed" unless somebody has messed with it. Most often done in a well intended but mis-guided effort to make it go faster. NOT.
 
Recently bought as a replacement. Have done compression check, had approximately 105 on each cylinder. Pulled all spark plugs and cranked with timing light connected to #1. At cranking speed, with the timer base against the screw, was showing to hit at 24 degree mark on flywheel. Have not tested on the water. Want to get everything set as close as I can before running.
 
TJN said:
Joe I believe so. Tested with timer base against rubber stopper and firing at 24 degree mark on flywheel
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Okay, I suspected as much.

Now, at cranking speed, with the timer base held up against the rubber stop, the full spark advance timing should show up 4 degrees less than what the actual timing is supposed to be.

That is....... Due to the electronics in the ignition system, when actually running at full throttle, the timing in your case would actually be 28 degrees ( 24 plus 4 = 28)... Meaning if the timing is actually supposed to be 28 at the full spark advance setting... your finding of 24 degrees at cranking speed is right on the button.

Right on the button?... Who in the Hell ever dreamed that saying up? :rolleyes:
 
Awesome! Feel better about taking it out this weekend. Will update after my test run. Thank you for the help!
 
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