Advice on how to remove broken bolt

So far no luck. I am going the easy out route since the left handed drill bit didn't grab the bolt enough to twist it out. However, these Ryobi easy out bits seem so brittle. It feels like it is going to snap off inside when I try and torque it manually. I'm afraid to use a drill and have it snap off. I'll keep trying. Today, I am going to try heating and cooling a few times to see if I can ease it out. Thanks for the help so far.
P
 
In the interim when your not working on it put a few drops of penetrating oil or WD-40 on the seam between the bolt and the shaft with the engine on it's side so gravity will draw the oil downward.It may not be visable to the eye but it will seep down along the threads with time and may assist with the extraction. Letting it sit overnight might be a good idea.
 
So far no luck. I am going the easy out route since the left handed drill bit didn't grab the bolt enough to twist it out. However, these Ryobi easy out bits seem so brittle. It feels like it is going to snap off inside when I try and torque it manually. I'm afraid to use a drill and have it snap off. I'll keep trying. Today, I am going to try heating and cooling a few times to see if I can ease it out. Thanks for the help so far.
P

That is why I recommend to step up the drill sizes. Enlarge the hole as far as you can without getting into the case threads. This will enable you to use a larger screw extractor.
 
I enlarged it to as far as I can go. Anymore and I am afraid I might be eating away at the threads. I had used loctite on the bolt that had broken off. I'm hoping by heating it I can release its hold.
 
I enlarged it to as far as I can go. Anymore and I am afraid I might be eating away at the threads. I had used loctite on the bolt that had broken off. I'm hoping by heating it I can release its hold.

Ummm, I don't think you ever mentioned using locktite on the bolt. Now you may need heat. Heat it up, and spray some PB Blaster (always good to have a can around the house), let cool and repeat. Then heat and go with the screw extractor. Do NOT heat with the screw extractor installed in the broken bolt. With heat, you will need to replace the seal, which isn't a problem.

I would remove the clutch gear, and remove the seal before heating it.
 
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OK! I am finally finished. Here's the skinny on what happened and why it took so long... The bolt would not budge. I tried heating it and spraying PB blaster on it, but I think it was just holding on too tight. The easy out would have worked, but I think I may have drilled too large a hole and when I was trying to screw it out with the easy out, there just wasn't enough bolt left to prevent any expansion so it was just digging into the threads. (My humble hypothesis). What I ended up doing was drilling practically all the way to the threads (The center punch idea came in handy bc I was able to get it centered practically perfectly). A friend of mine is a dentist so I asked him the other day if he had any used tools (The hardened steel tools with a hook on either end). Fortunately he had a few that he gave to me and they did the trick. I was able to pick out the metal from in between the threads and the loctite residue that was left over. Worked like a charm. Afterwards I re-assembled and took the bike out for a long stroll lol! Good to have her back running again. Thanks again for all your help guys. I hope this thread can help out others too.
Kind regards,
P
 
I've had good luck ' bunging ' broken bolts. Center punch outer edge, than take a long, sharp punch, and a light hammer, you might want to drill a little into the punch marks, just drill enough, aprox. 1 mm for tool to grip. with a few deft taps, the stub spins out. when a bolt breaks, tension against threads relaxes, and bolt spins easy. When a bolt breaks because of a jammed thread, the stub is not going anywhere, drilling the center takes pressure off threads. The Unicorn style easy outs tend to snap flush, I bought name brand ones at a lumber store, and they snapped flush, ruining expensive castings.
 
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