Confirmed: I'm the dumbest man alive

[DJ_Allatoona]

1986 Mercury 75HP. About three weeks ago I replaced the stator, trigger, and flywheel because I was having some random electrical weirdness that I blamed on the ignition system.

After I swapped the parts, the motor would start, but ran like garbage! Ridiculous lean, idle was screaming and I couldn't bring it down. Tried to set the timing, but it didn't respond to any adjustments. Bottom carburetor didn't even act like it was working. Motor was sick and I've been beating my brains trying to solve this.

I decided today to retrace my steps, put the old ignition parts back on, and start over again. Pulled the flywheel and instantly realized that when I put this replacement flywheel back on three weeks ago, I did not re-install it in the proper position on the hub. There's a special gap in the splines that SHOULD keep you from installing it incorrectly, but I just slapped it on and forced the nut down with an impact wrench. I never even thought that the exact position of the flywheel mattered. See the title of this post: I'm an idiot.

So today, after staring at it with my mouth open, I re-positioned the flywheel properly, put the boat in the water and it immediately started and idled nicely and I had a nice smooth 15-minute test run. Zero issues.

So learn from my rookie mistake: the flywheel CAN go on incorrectly, trust me. And you won't like the effect.
Here's the tooth I mangled on the crankshaft by forcing the flywheel down earlier this month.

 

[GA_Boater]

Dave - It takes a big man to admit a mistake. Glad you backtracked.

Anything else to share?

 

[The Force power]

The position of the flywheel is (the key) part of the timing. lol
I'm glad you got it solved and hey....you owed up to it. I bet you many would not.

I was about 15 or 16 when I was (trying) to get an old lawnmower going and I had tried everything I knew at the time.
It would fire & pull the pull-rope right out of my hands back into the recoil mechanism.
My Grandfather told me; it wants to start backward/run backwards & told me to check the key in the shaft.
sure enough...it was sheared, so the timing is off........way off

 

[Chris1956]

Force, A lot of Mercs do not have keys in the flywheel. The flywheel and crankshaft have "W" shaped splines that mate.

 

[The Force power]

Force, A lot of Mercs do not have keys in the flywheel. The flywheel and crankshaft have "W" shaped splines that mate.

Hi Chris,
I know that & that's not what I said, I said; The position of the flywheel is (the key) part of the timing.
the key = as in important

 

[Faztbullet]

Been doing this 40+ years and this is a first for me on a splined crankshaft....danged good impact!!!