Re: Broken studs
As for removing the broken studs, center punching the stud before drilling helps keep the drill bit centered. Make sure you get the punch exactly in the middle before hitting it. If the drill you're using is reversable then there are reverse direction drill bits that will help remove the stud. Sometimes they will back out while you're drilling. At least you used the right loctite product, blue, instead of the red stuff.
The breaking of motor mount studs is usually caused by either the engine not being seated well in the mounts, insufficient tightening of the nuts or bolts, or, mounting in any kind of resilient material such as rubber. You'll want the engine mounted as solid as possible with no movement or areas of non contact in the mounting surfaces. I have no idea what grade of all-thread you used but a better way is to get rid of the studs and go with either a grade 5 or 8 Allen head cap screw. There is no requirement to use studs and nuts. A bolt is a better choice and you only have one set of threads to be concerned with. I say use Allen head bolts because of the limited clearance provided in some places where a hex head will not clear.
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