How do you re-tap/thread a hole?

[The other Alex]

A bolt snapped off on my intake manifold, so I tried an easy out, it broke. So I drilled it out and took the threads with it, thinking I could just through bolt it, but the intake mani. extends downward and there isnt enough room to get a bolt on the bottom. So I'm wondering how I can re-thread the hole so I can bolt it on normally, or what my other options are...
Thanks, I feel like a dumbass.:Banane01:

 

[Kny21]

tap & die set.

 

[kingnothing3]

figure out what size hole you drilled and if you dont want to spend alot on an entire set, buy the tap individually. you can use a cresent wrench to do it but i would strongly suggest a tap wrench. run the tap down the hole slowly. get it started, then turn it half a turn right, then quarter back and repeat until you have threaded the hole all the way threw. MAKE SURE YOU USE SOME TAP MAGIC OR BEESWAX OR SOME TYPE OF LUBRICANT! you definatly do not want to break a tap in the hole. your only option then would be to use a edm machine to burn it out, and i doubt you have one handy. lol. well thats the quick answer if you want more detailed answer pm me. or im sure someone will post if i missed something.

 

[The other Alex]

I think I actually have a tap set, Ive just never had to use it. Haha, well this doesnt sound too hard as long as I take my time and do it right.
Thanks!

 

[casanova992]

Make sure you use some oil when tapping

 

[gj_fx1]

I dont really have the picture of what bolt broke here..but anyway tapping aluminum is easy. If you are tapping threads into cast iron and you never used a tap before I'd sugest finding a scrap piece and practicing. You dont want the tap to snap on you like the ez-out did. Who names those things anyway? They sometimes work but its never "easy"

 

[kingnothing3]

I dont really have the picture of what bolt broke here..but anyway tapping aluminum is easy. If you are tapping threads into cast iron and you never used a tap before I'd sugest finding a scrap piece and practicing. You dont want the tap to snap on you like the ez-out did. Who names those things anyway? They sometimes work but its never "easy"

i disagree, aluminum is actually the harder metal to tap because it is soft and tends to "stick" to the tap, drill, die, what ever you are using. because it sticks it can bind very easily. On the other hand iron is harder and does not stick to the tap. It could still bind the tap up but not nearly as easily as the aluminum. that is why it is so important to use lubrication on anything you tap.

I hate ez-outs. what are you supposed to do if you cant drill a damn hole! 80% of the time it is much easier to weld a new nut/bolt to the broken one and turn it out. unless it broke inside the threaded hole.:banghead:

 

[kingnothing3]

I think I actually have a tap set, Ive just never had to use it. Haha, well this doesnt sound too hard as long as I take my time and do it right.
Thanks!

make sure that is not a cheap tap set! cheap taps are not nearly the same quality as the pricey ones and they are very brittle. if it is a cheap set, be very carefull.