Lapping flywheel

[maineiac5586]

My 87 55 hp flywheel sheared a key and was a pita to remove the flywheel. I'm lapping in my replacement flywheel and wanted opinions on this pattern. I just set the flywheel on the crank but didn't put the nut on. You can see in the flywheel bore where the valve grind compound ends. Also on the crank snout. Thank you

 

[racerone]

How about pictures with compound cleaned off.

 

[tphoyt]

A little less compound would be helpful imo.
Also I once saw a guy coat the crank with a marker and rotated the flywheel on the shaft to check for wear points. I have never done it personally but it looked like it was a good way to check the fit.

 

[maineiac5586]

A couple with no compound. A little concerned with the shiny part at the top of the flywheel bore. Hoping that when the nut is tightened the flywheel will draw down to allow the shiny part to contact the crank snout. I did the lapping by just setting the flywheel on the crank not installing the nut. Once tightened will the top surface of the flywheel be even with the shoulder on the crank snout? Seems like it has to move down quite a bit. Thanks

 

[racerone]

Sorry mate-----The crankshaft fits on the taper.-----When you tighten the nut the flywheel is pushed down and " stretches " over the crank taper.-----The 2 are now locked together.----The locking fit drives the flywheel.----The key only lines it up for proper timing.----Yes that is the way it works.----On some years the key is the same part # on a 9.9 HP right to the mighty V-8 300 HP !!

 

[maineiac5586]

Sorry mate-----The crankshaft fits on the taper.-----When you tighten the nut the flywheel is pushed down and " stretches " over the crank taper.-----The 2 are now locked together.----The locking fit drives the flywheel.----The key only lines it up for proper timing.----Yes that is the way it works.----On some years the key is the same part # on a 9.9 HP right to the mighty V-8 300 HP !!

Do you think I'm going to be ok how it is? Do you sense something is wrong with what is pictured?

 

[racerone]

That should work.---Assemble it clean and dry.----On occasion I have seen some folks use grease on the tapers.-----I assume the thinking is that it will make it easier to pull off.-----Totally wrong thinking !

 

[maineiac5586]

That should work.---Assemble it clean and dry.----On occasion I have seen some folks use grease on the tapers.-----I assume the thinking is that it will make it easier to pull off.-----Totally wrong thinking !

Do you think the flywheel will pull down the rest of the way when tightened?

 

[racerone]

???----You might need a dial indicator to see how much it moves down when tightening the nut !

 

[maineiac5586]

???----You might need a dial indicator to see how much it moves down when tightening the nut !

Yeah I'm probably over thinking it. I'll just put her back on and torque the nut to 105 lb. Hope that will draw the flywheel down enough. I'm assuming the flywheel needs to go down far enough to cover the shiny area in the top of the flywheel bore?

 

[racerone]

Agreed----You are over thinking.-----The whole concept of taper ( locking ) fits is much mis understood !!----Just like many other " outboard motor " simple concepts.