Tapping/rethreading an aluminum block

Broke off header bolt, then broke off an easy-out. Assuming that I can get it all out, I’m also assuming I’ll damage the original threads.

Whats the real-world experience you’ve had retapped new threads.

Do you drill out to the next size up then tap? Is it that simple? 

1980 Suzuki GS850 engine (engine pulled from bike at the moment, I have easy access)

get a carbide/diamond tip for a dremile tool and cut straight into the middle or around the outside edge of the easy out, try to remove the easy out first, then back to work on the bolt. they are cheap at HF

Don't bother, get a timesert for the proper size and fix it once and permanently.

not a lot of fun, i can tell you that.  if you end up boogering the threads, you'll want to do a helicoil in order to keep the same size bolts through the header. 

Stefan said:

Don't bother, get a timesert for the proper size and fix it once and permanently.

THIS!  

Stefan said:

Don't bother, get a timesert for the proper size and fix it once and permanently.

The timesert will thread into the block using the damaged threads? I should probably learn more about this stuff. I’ve heard the terms hundreds of times but I’ve always somehow been successful with easy outs 

Edit: wow, just watched an animated video for timesert installation. Genius!

In reply to ebonyandivory :

You figured it out.  They work great and are often used instead of helicoils (both have their strengths and weaknesses).

but you still must remove the bolt first. I GUESS I HAVE DONE TOO MANY.

Weld a nut to the bolt/easy out then back it out.

Timecerts work well i favor Keenecerts as they have locking stakes so once in they don't come out.  Make sure to apply anti-seize to all exhaust bolts.

44Dwarf said:

Weld a nut to the bolt/easy out then back it out.

Timecerts work well i favor Keenecerts as they have locking stakes so once in they don't come out.  Make sure to apply anti-seize to all exhaust bolts.

Will do on the anti-seize! Everything unfortunately is below the surface of the head. I couldn’t get a nut on there.

Easy-Outs are hard but brittle.  I haven't done this, but I've heard you can hit them with a hammer and punch and they will shatter, then you can pick out the pieces.

Is the broken bolt even with or proud of the aluminum surface or is it severely subflush.  If it's close to the surface you can heat lightly with a butane torch and MIG weld a nut on the stud. I've found doing this and quenching with PB blaster to be quite successful on broken LS exhaust studs.

In reply to stuart in mn :

Tried MANY times to no avail 

Ram50Ron said:

Is the broken bolt even with or proud of the aluminum surface or is it severely subflush.  If it's close to the surface you can heat lightly with a butane torch and MIG weld a nut on the stud. I've found doing this and quenching with PB blaster to be quite successful on broken LS exhaust studs.

It was just sub flush when it broke. I was able to drill enough for the easy-out to grab it. Unfortunately easy-outs don’t seem to be up to the task they’re made for. I’ve since used a Dremel and got some of it ground out but the tool died.

Plan is to buy another Dremel with some carbide and/or diamond bits and just grind out as much as possible. I’m preparing to be successful hence the original question of new threads. 

Since you have to wait to get new tool heat it up as hot as you can then cram a candle in to the hole the hot wax will penetrant and help it come out once you do get your dremel in to it.

In reply to 44Dwarf :

I will actually do that, thanks!