Screw extraction help needed

[mr_maxime]

I broke 2 bolts on the engine and I tried a screw extractor but it broke off. Now I need some serious help. I'm in Pell City AL.

[dmcnc]

Could you specify which ones? Pictures would help too.

[mr_maxime]

Bottom of water pump and the dreaded bolt on the pain of agony. The water pump is the one I broke the extractor in. I've got a nut threaded on the pipe bolt. My intention is to weld the nut on and hopefully have the heat break it free. I've been hoping to get my coworker to come weld it for me but he hasn't had time.
https://i.imgur.com/iUkd5Zu.jpg

I found an article saying to dremel out the extractor so I've been doing that. I need to buy more grinding bits but it's mostly gone at this point. https://jalopnik.com/heres-how-you-remove-a-fractured-bolt-extractor-tip-fro-1746998630

[mr_maxime]

Broken extractor has been extracted

[Bitsyncmaster]

A screw extractor is really only good if you broke the bolt when you over tightened it. Never seems to work with a corroded bolt that broke trying to remove it.

[Ron]

$.02

I looks like you might have better results with the next size up extractor. Trick is to get one large enough that it doesn't break but small enough that it doesn't spread the remaining part of the bolt making it bite in and crack/break off the ear on the block...

Options:
If the threads are bad:
-Tap to the next size and enlarge the pump's hole.
-Weld the hole up and re-tap.
-Use a fully threaded bolt from behind (w/ HD Loctite), and a nut (w/o Loctite). (Might work well with a cracked or broken ear using HT Epoxy, depending on if there is enough left for a washered bolt head to pull against...relatively little stress.)

[FABombjoy]

2 of 3 of my water pump bolts are helicoiled. I can vouch for that as a working option.

[Ron]

+1!

[mr_maxime]

Thanks for the tips guy. Right now I got it fully drilled out to under 1/4". Once I get some short bits, I'll drill it to 6mm and try to chase the left over bits out with the m7 tap. If that doesn't work I already have a helicoil kit ready.

[mluder]

I'm late to the game here but it might be useful to others who stumble across this thread later.
I used a reverse drill bit - spins counterclockwise so its going in the direction of extraction. I started small and worked my way up to a size big enough for my screw extractor to get a good bite on the bolt.

Cheers
Steve

[mr_maxime]

Turned out to be not as dire as I originally imagined.

I didn't check the bolt size and bought stuff for m7 threads. I drilled it and tapped thinking it was strange that the seized bolt was bigger. I was able to knock part of it out with before drilling slightly larger and tapping with m8. Since the first couple of threads were clear I think I lined it up pretty well.

Sometime later today my coworker should come over and help me with the last one by welding the nut to the seized bolt. Again I'm hoping the heat helps it break loose and the nut gives me something to grab on to. I'll switch out the paper towels for aluminum foil to prevent a fire.

https://imgur.com/a/HRVbODr