Exhaust Bolt Broke Off

[djg42]

I was taking of my exhaust and one of the bolts holding the exhaust into the engine broke in half, with half in and nothing sticking out. I tried to use a bolt extractor to no avail. It just wouldnt ever grip the thing. Has anybody had any success in this department? I cant re-attach the exhaust until i get this thing out!
I tried heating it up, there is very little exposed at this point, not enough to grasp with anything. The other 3 came out ok and I have new replacements ready.
Thanks,

[Dave8338]

You may have to drill the thing out and retap or helicoil the thing. I would try stepping up your bit size, 1mm at a time and when the bolt gets to a 1mm "wall" thickness, the right size extractor will get it out.

[Guest]

I was taking of my exhaust and one of the bolts holding the exhaust into the engine broke in half, with half in and nothing sticking out. I tried to use a bolt extractor to no avail. It just wouldnt ever grip the thing. Has anybody had any success in this department? I cant re-attach the exhaust until i get this thing out!
I tried heating it up, there is very little exposed at this point, not enough to grasp with anything. The other 3 came out ok and I have new replacements ready.
Thanks,

Welcome to the busted bolt club

Do a search and odds are you'll have that exhaust re-installed lickity split.
If you'd have done it before you tried the easy out you wouldnt be posting this post.

Lots of info on the subject.

[doctorgonzo]

And when you reinstall slather the bolts with a healthy coating of anti-seize.

[djg42]

I decided to try the bolt extractor again. The ones I got have two sides, one to make a hole and one is the extractor. This time i used a regular drill bit to make the hole which works alot better. After I got a good hole i put the exctractor on and it fially gripped this time-the only thing is the screw still wont budge (the drill wont turn it-it stopped turning and began to smoke). CUrretly, the drill is sticking out of the engine!. I already sprayed a ton of PB blaster on it, but i put a ton more and am going to let it sit over night. Hopefully in the morning that SOB will come out

http://i837.photobucket.com/albums/zz293/djg42/IMG_0509.jpg

[doctorgonzo]

I decided to try the bolt extractor again. The ones I got have two sides, one to make a hole and one is the extractor. This time i used a regular drill bit to make the hole which works alot better. After I got a good hole i put the exctractor on and it fially gripped this time-the only thing is the screw still wot budge (the drill still wont turn it-it stopped turning and began to smoke). CUrretly, the drill is sticking out of the engine!. I already sprayed a ton of PB blaster on it, but i put a ton more and am going to let it sit over night. Hopefully in the morning that SOB will come out
http://i837.photobucket.com/albums/z...2/IMG_0509.jpg

Don't break the extractor off, then you'll be in even deeper. At this stage you probably need to drill it out and use an insert.

[Guest]

Don't break the extractor off, then you'll be in even deeper. At this stage you probably need to drill it out and use an insert.

I had to drill one but I didnt use an insert. Just drilled right to the edge of the original threads and retapped.
Just be sure and use new gaskets so ya dont have to torque so much.

[doctorgonzo]

I had to drill one but I didnt use an insert. Just drilled right to the edge of the original threads and retapped.
Just be sure and use new gaskets so ya dont have to torque so much.

Good point, may be able to just retap.
The biggie being, if you break off that hardened extractor in there, you'll have a hell of a time drilling it out, then you're loking at a new head, or at minimum a trip to the machine shop.

[Guest]

Good point, may be able to just retap.
The biggie being, if you break off that hardened extractor in there, you'll have a hell of a time drilling it out, then you're loking at a new head, or at minimum a trip to the machine shop.

I wouldnt even attempt to use an extractor.

I do it in steps.
1st, try to weld a bead on the busted stud, cut a groove in that and try the impact driver.
2nd, weld a nut to the busted bolt and if these two methods dont work I start drilling with counter clockwise bits in hopes of getting lucky, starting very small and using the other holes as a depth guide. Eye balling the hole() being very sure I keep it centered as much as pos.
(I dont think the first two methods have ever worked for me)
And do everyone a favor, if ya dont have the correct size "metric" tap, get one.

[djg42]

Thanks!
There is not enough exposed to try and weld anything to it.
Im not sure how to re-tap it/ive never done it before-
Basically you drill all they way through the bolt, and then you attach a bit that "re-taps" it? What size bit shoul i drill the broken bolt with?

[doctorgonzo]

Thanks!
There is not enough exposed to try and weld anything to it.
Im not sure how to re-tap it/ive never done it before-
Basically you drill all they way through the bolt, and then you attach a bit that "re-taps" it? What size bit shoul i drill the broken bolt with?

You drill it out with a bit JUST smaller than the original bolt, being careful not to drill too deep and break through into an oil gallery, then you tap it with a tap and die set. I'd take it to a machine shop, tell them to drill it out and retap it M8 X1.25. If you've never done it, you are rolling the dice on drilling crooked, or drilling too deep and breaking into an oil gallery, etc...

[Audioslave784]

This happened to me on 3 of the 8 exhaust bolts on my bike. DO NOT use a screw extractor, mine wasn't even close to moving the bolt before it broke.

I didn't want to take the engine to a dealer if there was any chance I could get them out myself. But after breaking the screw extractor in one bolt and drilling a crooked hole through another, I ended up taking it to a dealer. They drilled out the bolts and installed thread inserts. 1.5 hours labor plus supplies ran almost $200, but it should be much cheaper if you've only got one broken bolt, and it's still a lot cheaper than messing up your head.

It's not that you couldn't do the job yourself, but if it would be your first time drilling a bolt and installing an insert then I think this risks highly outweigh the money saved.

[Guest]

Anyone seen Chris Cornell?

[Guest]

If it were me... (and I say this as a guy who's broken a few exhaust bolts off in a couple of heads):

Keep spraying with PB Blaster, several times a day. Bite the bullet & remove the head. Buy a head gasket. Find a good aerospace TIG welder, and have them weld a steel bolt to the flush broken bolt (don't worry, the welding will not mess up the alum). Keep spraying with PB Blaster.

Now you have a bolt head you can put a wrench/socket on - if you break the bolt off re-weld it back on & try to twist it out again.

The heat of the welding will heat that broken bolt up cherry red, and in doing so will break the chemical/physical galvanic corrosion bond between the disimilar materials (steel bolt/alum head).

This has worked for me with zero negative effects on the aluminum. The key to success is to find a very good TIG welder.

The benefits are one-day turnaround, welder shouldn't cost too much (as compared to machine shop), & no machining/heli-coils needed. Buy a good quality (4 flute) tap & simply chase all the threaded exhaust bolt holes.

[Nessism]

Every time I read one of these "broken exhaust bolt" threads it makes me cringe, there are ways to extract these bolts without breaking them but people just don't research before they get all heavy handed.