Generator draw stud question

[Trefor]

Could somebody confirm the diameter of the generator draw stud hole in the crankcase of a '53 G9? A previous owner had stripped the draw stud thread in the generator end plate and repaired it with a 1/4" helicoil. I think they then drilled out the hole in the crankcase to 1/4 to accommodate a 1/4 Allen bolt causing a small piece of the inner aperture though which the generator fits to break off. I think the hole should be 3/16". Thanks

[Groily]

I think 3/16ths, yes, to give a reasonable clearance on the 2BA original diameter of the stud (4.7mm).
(I've got one that's been enlarged too, but luckily no damage done to the surrounding metal so I live with it and an oversized draw stud.)

[Trefor]

Thanks for that info, Groily. I'll make a sleeve and use some epoxy.