Tips on broken bolt removal

[samuel642000]

A couple ideas that have worked in various situations, when I didn't have a bolt extractor.

Sometimes a busted bolt will come out easy, some light taps with a tool, see if it will come out with pliers, only moderate force. Spray some penetrating lubricant on the threads, wait a couple minutes, try the pliers again.

For tighter bolts
Use a small drill bit, drill 3 holes in a line across the bolt close as you can.
It can be important to get the first hole centered well. You may need to plane the surface flatter, use a punch marker to make the initial dent for drilling.

Now you get to use experience and judgement.
You can tap a flat head screwdriver into the 3 holes. Spray some penetrating lube on the threads and unscrew the bolt out.

Or, you can use the 3holes as a good grip edge for welding the bolt to a nut.
Wait until it cools most of the way, spray some penetrating lubricant into the threads, then put a piece of ice on the nut to help shrink the nut and bolt while the block/boss is still warm.
Unscrew the nut and bolt.

Lastly, you can center drill it, short of the threads(check size by inserting bit into another bolt hole), then use a flat head to tap one side of the bolt threads into the center, insert a screwdriver so it's wedged against the edge of the threads and lightly tap out. Little, if any, thread damage if done carefully.

Good luck.

Some good tips that I've never known, storing that in the memory for future use.

[d1tko]

I had a bolt that was broke on Motorhomes exhaust manifold causing and exhaust leak. I removed the manifold and when I drilled it out the damn bit broke off inside the bolt. I had to do this to 2 others as well but didn't have the bit break off.
Any tips on how to get it out now since the bit is in there? Any special bit that can drill that out?

weld a nut on top of it and use a wrench...

[DFWtechie]

I got them it out yesterday, I drilled it with small bits and then took a chisel and chipped away at it for a awhile, I used left handed drill bits on it in hopes it would remove it. The broke bit broke up into small chips and then the bolt came out.
This was a huge pain the ass.

[shumpertdavid]

congratulations on getting it out sir. Those jobs come with a slight feeling of satisfaction at the end, and a huge regret for taking it on a lot of times.

[46Tbird]

Glad to hear you got it resolved.

This happens to me often enough that I would never want to make my living as a mechanic.

[shumpertdavid]

bastard thread, customer today informed me along with the repairs then originally brought the truck in for, they would also like to fix the exhaust leak. Yep, broken bolt in the head....

[DFWtechie]

Sorry David to bring you bad luck with crap. I hope to never have to deal with this again. It was a little easier because it was motor home and I could get it fairly easy but it is still a bitch.

[shumpertdavid]

It's just part of it, 98 ram, v6, both drivers rear studs broke in the head, moved master cylinder to side, pulled brake booster, steering shaft, and manifold, drilled through the broken studs and soaked wih lube, headed head around bolt hole and tried to remove with ease out. No dice there so drilled to 17/64 and retapped holes to 5/16-18. Took about 4 hours to get to this point. I'll hopefully get new hardware tomorrow and reassembled.