funny you should ask. i just dug out a Craftsman 3.7 i rescued from the trash years ago. It had the same problem: the front stud had pulled its threads, & the owner tossed it.
I drilled out the hole with the correct tap & installed a heli coil. they sell them at the hardware store, along with the helicoil tap, and it says what size drill bit to use.....
Can you email me the numbers on your bar? I never got around to getting a bar & chain, & I dont know what pitch, etc. It says "!8 in"
on the housing.... neoludd@earthlink.net
mutt, April 2007