Found "tungsten carbide" dremel bits, they seem to be the toughest material. Should hold up and help a lot in cutting away the bolt....hopefully.

 

The dremel bit practically ate through the bolt, but it wasn't long enough to actually get down in there and remove all the bolt. I can't see all the way down when using the dremel so it would be more risky. I used a 1/4" reverse thread drill bit and with no problems drilled through the bolt. BUT, now I can't get it to go any further which makes me think that I am through the bolt and bumping the bottom of the snout( bolt is completely bottomed out). The extractor grabs very well yet there isn't enough resistance from the gears to hold steady, the crank just keeps spinning and I have no way of holding pressure against it so I can turn the extractor. The next size up drill bit is 19/64 so I'll use it and see how that goes but that will be cutting close.

Am I just stuck now and have to drill out the whole thing and rethread? How difficult is rethreading the crank/drilling the larger hole in the snout?

****what size would I need for the new hole (drill bit) so I can use a thread repair insert kit to bring it back to normal 7/16-20 threads? Not sure if I want to use an insert or just drill bigger hole and rethread, but that means redrilling the center hole on the hub as well.

 

Piston Stop Tool
I would save the over-drill and tap option as a last resort. Maybe pick someone's brain at a machine shop to tell you what your odds are for doing that without performing a tap snap.

 

pull the flywheel cover off and clamp a set of vice grips to the flywheel. clamp it so its not to hard and your on a even section of it so it will not do any damage.

 

I have been thinking about trying to get it out with an extractor again. Since I seated it people have said that it is "thread locked" and no matter what the extractor will not get it out. I also don't want to risk breaking the extractor off after all this time trying to drill out the bolt to begin with.

Talked to a guy at advance and he said if I use an insert then I want to drill the hole 1/64" bigger then the size I need. So in this case, I want a 7/16" hole/insert so I would drill my hole 29/64". Is that how it works or would that be wrong?

I already have a tap set, and if I can save more cash by just buying a drill bit and the 7/16 insert over a whole insert set that would be great.

From what I read, I would drill the new hole...rethread the new hole with the same thread count I need (20)...then the insert should slide right in and adjust the actual threading and size back to what I need. Does that short explanation make sense?

 

What about a set like this? Not sure of the brand "helical"...?

Helical Thread Repair Kit, 7/16-20, 18 Pcs - Thread Insert Kits - Thread Insert - 5WE94 : Grainger Industrial Supply

 

"Helical", is that supposed to be a Heli-coil knockoff by using name confusion. You have been using your Craftswoman drill, right?

 

I can't find quality reviews on the brand, so I'll stay clear. Heck I don't know, just looking for a cheaper alternative to the $100+ timesert kits.

I'll need the 29/64 drill bit, the 7/16-20 inserts, install tool, and threadlock that biznatch for peace of mind.

 

Make sure the drill size is what is recommended by the Tap manufacture and that tap is the designed to worth with the insert you by. There is a lot variation across manufacture of these types of inserts. It is very important to make sure the tap goes in straight, Pro will always use a tap guide even to the point if there is a uneven ridge I have seen them make up spacers to be sure the tap is going in straight.

Did you ever try the left handed drill bit Camaro 69 sugested? Most of the time I can get that to work. Even a few cars that came in from guy that have spent hours trying to get bolts out my handly left hand drill bit just walked them out. It really pissed off the guys that stuck around and watched me do it.

 

Yes I tried the left hand bits, used 1/4" and a 19/64 bits with no luck. The bolt is bottomed out and thread locked I guess. I would use the extractor on the little bit remaining and like I mentioned the crank and gears would just turn since there isn't enough pressure to hold it from moving while I turn.

So here's the new plan. Skipping the insert method and going straight to rethreading. I'll drill a bigger hole, rethread that new hole, then use a bigger bolt. I'll also have to redrill the hub. I'm stepping up to a 1/2" and I grabbed a 1/2" cobalt & tungsten with carbide tip. Pretty long bit so hopefully when in the drill I have enough space to position correctly or I'll end up having to remove the radiator and condenser for more room...hopefully not have to. Got plenty of cutting/threading fluid and a bigger t-wrench for the tap. How's this idea sound?