Just twisted off an intake manifold bolt!!!

[68 TT]

Originally Posted by El Jay

Good advice.

To add a bit to it, I'd have everything set up & ready to go; bolt center punched & the drill loaded & ready to go.
After heating the bolt, I'd hit it with a candle to get some wax down into the threads & then start drilling with the reverse twist drill. The tip of the bolt is a little harder than the rest and when the drill hits the end, it will try to bind & back the bolt out.
If this doesn't work, then you already have a hole drilled for your E-Z out.

I was a machinist in the air force for 13 years and removed on average 20 broken or damaged fasteners per day.

Make sure you use a die grinder with a ball end carbide cutter on the head of the broken off bolt. The irregular surface will damage your drill bit and/or make it walk to the side damaging the intake.

Make sure you are drilling perfectly parallel with the center line of the bolt with the left hand drill bit or it will break the drill bit when the bolt starts to come out.

A 1/4" left hand drill bit will work well on the 3/8" intake bolts.

If you have a hammer drill use it. The shock will help break the fastener loose.