Oops...how do I remove a broken bolt?

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Monjebricks

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Ok so as I am getting ready to go on a nighttime ride I check over my valve covers to see about an oil leak that was going on. I realize that one of the nuts was loose and I decide to tighten it. I notice that I kept turning the nut and still no grip. Turns out the nut was broken and half of it is still in the cylinder head. My question is how do I get it out and replace it!! :twisted: !please help thanks!

-angel
 
Generally not in there that tight so try a reverse drill bit first level of attack. Next level is drill very carefully to get an ease-out spiral extractor. If that don't work a machine shop can drill the guts out of the stud and then just twist out. Nitric acid does not attack the head alloy but turns steel of redish mush to flush out till just a nubbin left to pick out. Clay damn is used to hold acid around hole. Electro obliteration is another expensive option. If a really good stick welder they can stick on a rod the heats the snot out of the stud and sticks to it, then wait 30 sec for heat to flow into head then twist out like hors d'oeurve on a tooth pick.

I don't like the flash back to these methods that had to be used on my first Combat then big lawn mower.
 
Valve cover? Broken stud?
I can't say as if I've ever seen that happen before.
I would appreciate it if you posted a pic.
 
I thought subject was a bolt and half a nut in head was a typo. If can see to fish out then off with her head to shake out but could go down pushrod tunnels onto lifters. I've sucked hidden stuff out with vacuum hooked to small tubes but don't think will help you.
 
OP said broken Bolt in the thread title and broken Nut in the post,
but, he said that he was trying to tighten down the valve cover.
Now.....I'm not sure exactly what is broken or where.
 
With the cover off is there any bit of the stud outside of the head, if there is a bit out you mite be able to clamp a small vicegrip on to it and undo it, if its broken right inside the head you can drill it out with a drill that isan't as wide as the broken stud but make sure you centre punch the broken bit in the middle so the drill can go in straight and have the right size ezayout to fit the hole you are drilling, but make sure you drill it straight, if the ezayout don't get it then you will have to drill it with a bigger drill, but under the size of the thread, but you will have to have a tap the same size as the stud thread.

I have done this with a few broken studs/bolts before over the years and has worked for me, just take your time and make sure you do it straight, but it all depends on how hard the stud/bolt is as well, but it should be OK.

Ashley
 
To clarify: the BOLT is broken inside the thread of the head. The nut is fine as well as the valve cover.
 
Assuming the stud is sheared flush with the head - The last time I had this happen I used a mig welder to build up a good sized blob of weld on the top of the stud, and it was easy to get a vice-grip on the blob and just unscrew the stud - the mig generates so much heat that there's no resistance from the alloy head - the key is to do it while it's still hot.
 
There are two types of easy-outs that I know of: ones with a left-hand spiral "thread", and ones with a tapered square shank. Either should do the job, with a suitable sized hole drilled down the middle of the broken stud. The square type is gently tapped with a hammer to make it bite into the stud, and this also helps to shock the thread loose. The stud should not be very tight in the head, but if it won't budge with moderate force, you could try gently heating that part of the head with a gas torch.
Good luck
Martin
 
I've learned my Commando lesion on trying to remove anything that don't start moving pretty easy right off, start up the Torch!
Here's what I'd try first while a hair drier heat gun is keeping head toasty w/o fire hazard.

http://www.harborfreight.com/13-piece-l ... 95146.html

If the threads get buggered up I've had success with off the shelf epoxy thread remaker/repair on time cover screws so may work a treat closer to the exhaust heat. If that don't do it then there are off the shelf studs with a bigger bottom section to fit in new bigger hole and new threads.

http://www.google.com/#hl=en&sclient=ps ... 39&bih=600
 
Oops...how do I remove a broken bolt?

gingerly .

& with a positive demeanour once it figured . GOOD mole Grips if theres anything protrudeing .
Might thread through if snapped at thread top if holes not blind .
 
Ugh Matt does have a valid point, a mood modifier is not a bad idea to steady hands and mood to focus and not get too ruffled if the worse happens ...as has happened.
 
I'm not sure if those studs are in blind holes or not. And I am not where I can take a look. If not blind try to screw it right through, but it might be broken because some idiot threaded the wrong stud into the hole. B+ had a good idea on using a mig welder for steel as it will not stick to the alloy, just the stud. The heat helps too. If you place a nut over the broken stud and fill in the hole in the nut so that it sticks to the stud, then you can grab it with a wrench and twist it out.

Russ
 
I think the top rocker studs break through to oil as famous for weeping oil up their threads. The lower one is definitely blind hole unless broke.
 
The most important thing is to get the punch mark in the center of the stud if your going the easy out route Its not to often you get a second chance at it

Phil
 
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