Flywheel is wobbling

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Smutty

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My 2006 outboar Yamaha is a 2 stroke 2 cylinder 25 hp #25MSH I did a pretty good tune up on it and it now starts first pull but the flywheel seems to be wobbling and motor is shaking a good bit its torqued down at the required specs at 70 ft pounds any ideas would be appreciated here’s a link for a video of it
https://youtu.be/r2kt9ZfifKI
 

Grub54891

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It looks like its moving up and down. Don't know why. See if you can lift it up and doun.
 

flyingscott

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Pull the flywheel off again and make sure everything is PERFECTLY clean. My guess is the flywheel pushed the key down and jammed.
 

gm280

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If you verify everything is absolutely correct with the installation and torquing, the only other option is a bent crankshaft?
 

racerone

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Fairly obvious to me that perhaps someone tried to remove the flywheel with a 3 jaw puller.----Examine the outside of it to see if you can find the puller marks.
 

Smutty

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Fairly obvious to me that perhaps someone tried to remove the flywheel with a 3 jaw puller.----Examine the outside of it to see if you can find the puller marks.
I’ll will check it again but I got this motor sitting at someone’s house I already pulled the flywheel of just without a pulled tho the other side of it looks a little messed up I’ll try to get some photos of it tell me if y’all think it could be the reason please
 

Smutty

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If you verify everything is absolutely correct with the installation and torquing, the only other option is a bent crankshaft?


Could you click on the other link and check the photos of the flywheel and do you think that could be the reason
 

Smutty

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Pull the flywheel off again and make sure everything is PERFECTLY clean. My guess is the flywheel pushed the key down and jammed.

I have new keys coming in tomorrow so I’ll probab be pulling it off to replace it and will update you on what it looked like
 

gm280

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Could you click on the other link and check the photos of the flywheel and do you think that could be the reason
.
Well that does look like the center is got some issues. The only way to verify the crankshaft is bend or not is to take something, most anything that you can secure to the engine housing to make sure it doesn't move and have it pointed on the shaft itself. As close as you can would be the best (some use a dial indicator for this) and then slowly turn the engine shaft over and see it the pointer gets closer or further away from the shaft. If it stays in place and you don't see any different as you turn teh shaft, then the crank isn't bent. But if you do see the distant change as you turn, they's your problem...JMHO
 

Grub54891

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I see the inner taper is chewed up also. I think the key sheared in the past and spun the flywheel, messing it up.
 

Smutty

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.
Well that does look like the center is got some issues. The only way to verify the crankshaft is bend or not is to take something, most anything that you can secure to the engine housing to make sure it doesn't move and have it pointed on the shaft itself. As close as you can would be the best (some use a dial indicator for this) and then slowly turn the engine shaft over and see it the pointer gets closer or further away from the shaft. If it stays in place and you don't see any different as you turn teh shaft, then the crank isn't bent. But if you do see the distant change as you turn, they's your problem...JMHO


So I wasn’t sure what you meant on the steps checking the crank shaft but I did go back out and pulled the flywheel off took another video without the key in it https://youtu.be/hjYiGgWAO3s please watch the video I have 2 more photos that I’ll be uploading on the other site soon if you wanna check those out also
 

Sea Rider

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After replacing the key for a new one, was the issue fixed or remains same ?

Happy Boating
 

Sea Rider

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The upper crankshaft relies on 2 large plane bearings, both could have achieved excessive axial wear. Remove the flywheel and wiggle hard with fingers the upper crankshaft's play to rule that out, if found with tiny whiny side play will need to open the crankcase and change both upper and lower plane bearings as well for a smooth motor operation...

The wear could be due to high hour use, poor lubrication, bad quality 2 strokes oil or mixed in the wrong fuel/oil proportion ?

Report your finding ?

Happy Boating
 

Smutty

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The upper crankshaft relies on 2 large plane bearings, both could have achieved excessive axial wear. Remove the flywheel and wiggle hard with fingers the upper crankshaft's play to rule that out, if found with tiny whiny side play will need to open the crankcase and change both upper and lower plane bearings as well for a smooth motor operation...

The wear could be due to high hour use, poor lubrication, bad quality 2 strokes oil or mixed in the wrong fuel/oil proportion ?

Report your finding ?

Happy Boating
I removed the flywheel and tried to wiggle the shaft no slack in it it’s solid
 

racerone

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I would say the problem is with the flywheel.----Time to look for a new or used one on E-Bay perhaps.
 

Smutty

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I would say the problem is with the flywheel.----Time to look for a new or used one on E-Bay perhaps.

I’ve got one on the way should be getting it tomorrow along with a bunch of rain but as soon as we get a clear day I’ll be installing it updating everyone along with another video to show if it’s still same problem or not but if it is the same problem I’m not sure where I’d go from there I’m not really wanting to pull the crank off really unless absolutely necessary
 
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