Removing broken bolts

[Craig 2000 TA]

Hi all... pulled my Pontiac 400 from my 77 TA parts car last night and in the process two bolts snapped off. I was wonderring if anyone knew of any good ways to get them out other then drilling. I am thinking about having the engine professionally cleaned, painted and rebuilt with performance goodies and I figure if i go that route I could just have the shop do it.... but if I do it myself anyone have any tricks?

[Coop '02Z]

well...

There is a tool called an EZ out...That's probably your only choice but they do involve drilling...You drill a hole in the center of the bolt, tap this thing in there (it's like a reverse spiral) when you tap it into the hole you drilled it wedges in. then you use a crescent wrench or tap handle to turn it and it will (should) allow you to unscrew the bolt.

[Spades95formula]

yup,hes right, you can find it at any parts store for about $7 bucks

[Craig 2000 TA]

Thanks for the input guys... I'll check into it.

[Joe 1320]

Make darn sure you soak the remaining part of the broken bolt with PBlaster. If not, and you break off the EZ out, you are screwed as that stuff is hardened steel. You won't be drilling that out a second time.

[Black97]

If not, and you break off the EZ out, you are screwed as that stuff is hardened steel. You won't be drilling that out a second time.

The only thing you can do at that point is have it professionally removed by spark machining or if I translate it word by word from German it be "spark erosion".

In the factory they used that to remove broken off taps and drill bits in huge pieces which had rather large price tag.

[Jeff_in_Atl]

That machine is called an EDM machine. Electronic discharge machine. It sort of works like a mini welder where it burns the material away. A lot of people call them ELOX machines because ELOX is the biggest manugacturer of them. A hate the fluid used in them. It stinks. I have burned out a many of broken taps in one.

The hardest part of removing the screw is geting the hole drilled in the screw. The screw is harder than the material it is screwed in to so if the drill starts walking off, it will move to drilling the surounding material instead. Unless you've done it before, You would be risking scrapping what you are trying to salvage. I doubt a shop would charge that much for removing it. I used to be a machinist and I wouldn't do it. It wouldn't hurt to call and ask before you try it.

[Black97]

The hardest part of removing the screw is geting the hole drilled in the screw. The screw is harder than the material it is screwed in to so if the drill starts walking off, it will move to drilling the surounding material instead. Unless you've done it before, You would be risking scrapping what you are trying to salvage.

Jeff is right. It is important to get a good start when drilling the hole into the broken off piece for the extractor. You want it dead center and in the axis of the bolt to avoid running into the other part.

This is rather difficult with a hand drill. If it comes really bad you may even brake the drill bit off.

You'd be better off with a shop drill that has a table with a vise you can clamp your part into. To get a good hole started you could use then a more stable centering drill bit (used to drill a centering hole used on a lathe).

[Craig 2000 TA]

All good info... thanks guys... I tried to use and easy out and sure enough... it snapped right off so now a small piece of it is stuck in there too. I guess I will leave it there and have a machine shop take care of it when i have the engine re-worked.