69 johnson 40 hp question

[bigtrout29]

Hey guys bought a 69 johnson 40 hp guy I bought it from say when it run it runs great but then the can keyway breaks under the fly wheel any suggestion on why it does was thinking the timing is off any help would be great thanks

 

[racerone]

Follow these instructions.------Get a factory replacement key.---Hardware store standard keys will not do here.--------Use some valve grinding compound to lap the flywheel and crank tapers for a perfect fit.-----The key locates the flywheel for proper spark.-----The locking tapers drive the flywheeel.----------Torque the nut to 105 FT-LBS.

 

[kimcrwbr1]

+1 The flywheel will shear a new key if the tapers do not fit tight even if you torque the flywheel to 105ft lbs. While you have the flywheel I highly recommend replacing the points and condensers. Gap the points at exactly .020. Also if the coils are cracked replace both with new or they will fail when you dont want it to.

 

[bigtrout29]

Thanks guys figured it was something minor I planned on checking everything under there and fine tuning thanks again

 

[kimcrwbr1]

What I do is wrap a oil soaked strip of cloth around the crank on the upper seal and dress up the crank with a fine file, its easy to find the high spot/s. Then use emery cloth for the flywheel taper.
If the points plate wiggles up and down get a new ring and bracket to tighten it up. Just a little wobble and the timing will jump around giving performance issues. Real common if it has not been upgraded.