Koehler ZT740 in a pond

[slomo]

Getting a solid answer from these guys is tough. Key is good. Key is not good now. Well now that you think about it, it's good again. Okay what key are we talking about? Frustrating.

Your flywheel key needs to be in pristine condition on all sides. End of message on that. The keyway, where the key rides, same deal. Pristine condition all around. Flywheel nut needs to be torqued to factory specs.

What about this drastic overheating issue? Do you have the top engine shroud off? Cooling fins plugged up with swamp mud and grass?

What are you using to test this extreme temperature with? Is this just oil burning off or what?

Post up a video so we can see what you are trying to type about.

 

[bertsmobile1]

Check the key ways for tiny burrs and file them off with a fine file
Then get some lapping compound and lap the flywheel to the crankshaft as proper close fit on the taper is essential for it to work .

 

[VegetiveSteam]

Pulled the flywheel again today and found the key was sheared. Timing has been way off as a result. I’m sure I can get some keystock at a local auto parts house. Anyone have any idea how big that key is? It was completely obliterated and I have nothing to go on. All parts diagrams only show a part number. No dimensions. Thanks for all the help guys!

When you put it back together make sure the taper on the crankshaft and the taper inside the flywheel is clean and dry. Torque to 55 ft lbs.

There will be those who say they do it all the time with no issues but my recommendation is never use an impact on a flywheel fastener to remove or install as it can cause damage to the flywheel magnets.

An interesting tidbit just for fun, if you can line up the keyways of the flywheel and the crankshaft, and keep them from moving as you torque the flywheel fastener, you theoretically would have no need for the key. The key just makes it easier to line up the keyways and actually does nothing once you properly torque the flywheel fastener. Keeping the keyways lined up as you torque the flywheel fastener can be a bit of a challenge. Obviously I don't recommend that but it's something I would have fun showing in some of my classes if I had some extra time.

 

[bertsmobile1]

Can't see any mechanism for damaging the magnets other than shaking them loose off the flywheel.
I have seen tapers badly damaged by forcing it down over a burr and even over tightening and deforming the taper .
But yes the taper has to be clean smooth dry & a close fit

 

[Ebtate8]

Flywheel key was sheared. Put a new key in and reassembled. All is great now. Thank you to everyone for the help.