Re: Drilling and Tapping JB weld
In a word, no. JB weld will fail under motor mount stress. It might hold a minute, but vibration WILL get it soon.
Much better idea is to tap it out larger to reach undamaged metal.
Or a Helicoil if possible. This fixes threads stronger than new.
If more is better, then too much is just enough.
If you can't afford it, build it yourself.