Originally Posted by babywag
Did you have the rotating assembly balanced when engine was rebuilt?
A misfire can also cause vibration or bad motor mount.
Could be other things as well.
I don't know if they do that on a typical engine remanufacturer not. S&J should know what they're doing?
Switched mounts to the red poly ones. Seems good and tight. I checked at rolling in neutral and no vibrations to rule out any drivetrain issues. It's smooths out at 35mph and over 70.
Should be too much a job to swap out and see if it goes away I suppose. It's also possible I didn't tighten the balancer down all the way but it looks to be snug. Maybe I could tap it and wrench it to see if it tightens some more.
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