[AT] Drill size for bolt tap question

[Al Jones]

I've got some wallered out holes on a Farmall Super A torque tube that I
want to fix.  They need to be 5/8" coarse thread, but somebody stripped 'em
out, then did some sort of funky drilling, and now my holes are 15/16" in
diameter.  I'd like to fix it myself but the longer I look at it the more I
fear a machine shop visit is in order.

My notion is to try to tap the holes for a threaded insert.  If I drill the
holes out any larger for a larger tap, it's going to eat away the square
boss on the side of the torque tube, so I want to avoid that. Now, the
chart I am looking at says you need a 7/8" hole for a 1" tap. That means
the existing holes are 1/16" too big.  Can I still tap it with the 1" tap,
Loctite the daylights out of the insert, and get it to hold? These holes
are on the left side, and there weren't many implements that used these
holes, plus it's going to be mainly a show/plow day tractor.  But I do want
them functional and they have to "look good."

I have a good torque tube, but this is an early (probably built the first
or second day of 1950 production) white demonstrator tractor, so I'm trying
to keep the castings original.

thanks!
Al
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