After breaking an ez-out, spending half a day dremeling out the extractor, then breaking a dremel burr, using a punch to pulverize the burr, then finally getting to drilling the bolt with a bigger bit (close to threads), the fricken bit breaks and is now lodged in the bolt. I am sick of this. I spent several days wrestling this single bolt and I don't want to work on it anymore. No EDM machines local, and I really do not want to take my bike to get it worked on anywhere. This bit is going nowhere. 3 of these goddamn bolts are broken and only one came out. (yes, I tried torch, soaking it in penetrating oil, etc before they broke)
I read somewhere with broken bolts, you can use a hole saw to cut around the bolt and then tap and helicoil the thing. Would the saw bit work the cylinder head? Aluminum, right? Where can I find a small hole saw? The smallest I can find are over 1/2 inches.
Any alternatives to securing the exhaust headers? i.e. any way to install the exhaust headers without using the bolt locations in the cylinder head? Thanks.
I just thuoght about this and realized its a dumb question. How the heck am I going to get the cut-out removed? lol. damn.
Any advice on getting this drill bit out?
Get the head off and take it to a pro before you end up damaging it beyond repair........if you havent already.
not damaged. nothing touched except for the bolt. I drilled it center. I'm looking for specific help on this situation.
I've given enough thought about if and when I should take it to a shop. Unfortunately, there are no places locally that has an EDM. I'm going to try a few more things and when I run out of options and feel like I'm going to end up making this thing irrepairable or damage the head, I'll take it in. Or get a used head.
BTW the drill bit is a cobalt one (not the brand kobalt). I'm reading things saying I could shatter it by hitting it counter-clockwise. However, I'm worried about cracking something on head by hammering it really hard.
Ok how much of the broken bit do you have sticking out? Can you grind some flats on it w/ a dremel and use a tap handle to turn it out? Vise grips? Or weld a piece of stock on for a T handle; the weld heat should expand things enough to turn it back out (use heavy gloves). Otherwise you are looking at a carbide burr in a dremel; very easy to ruin things with one so be careful.....don't work on it to the point you get exasperated with it....take breaks. They make spiral ez-outs as well. Don't be afraid to grind the e-z out to length if you find yourself between sizes.
The question is what are you trying to take off?
he broke off the exhaust mount bolts in the head
Quote from: dwkfym on May 13, 2009, 05:12:03 PM
not damaged. nothing touched except for the bolt. I drilled it center. I'm looking for specific help on this situation.
I've given enough thought about if and when I should take it to a shop. Unfortunately, there are no places locally that has an EDM. I'm going to try a few more things and when I run out of options and feel like I'm going to end up making this thing irrepairable or damage the head, I'll take it in. Or get a used head.
BTW the drill bit is a cobalt one (not the brand kobalt). I'm reading things saying I could shatter it by hitting it counter-clockwise. However, I'm worried about cracking something on head by hammering it really hard.
You don't need an EDM, that would be overkill. It isn't a through hole either, so you'd not only have to find a shop with an EDM, it would have to be a plunge EDM and not the more common wire EDM. You just need a guy with a nice mill who knows how to use it. Just get a machinist to use an end mill to mill out the bolt and a bit of the material around it. Tap the hole, insert a helicoil that matches the thread pitch and diameter of the original header bolt and and get on your way. Easy for someone with the right tools and it will end up stronger than the original. You need to make sure and use an end mill when going into the aluminum. If you use a drill, it will walk off the hardened bolt and into the aluminum and leave you with an oval, which is very not good. I've used this solution on all of the front rotor bolts of my project bike and I have full confidence that it is stronger than the original. This should be easy. I did it with a bridgeport in the shop at work and I was able to do 5 of them in a half hour and I'm a programmer who pretends to be a bad machinist after work...
One more thing, when taking the head off, make sure you don't loose any of the crush washers down into the engine. Trust me, you don't want to do that, it will take you hours to find and you'll need a whole fist full of new gaskets.
Quote from: dwkfym on May 13, 2009, 05:12:03 PM
and when I run out of options
Your out of options now.
Thanks for the advice so far.
Quote from: fred on May 13, 2009, 11:26:26 PM
You don't need an EDM, that would be overkill. It isn't a through hole either, so you'd not only have to find a shop with an EDM, it would have to be a plunge EDM and not the more common wire EDM. You just need a guy with a nice mill who knows how to use it. Just get a machinist to use an end mill to mill out the bolt and a bit of the material around it. Tap the hole, insert a helicoil that matches the thread pitch and diameter of the original header bolt and and get on your way. Easy for someone with the right tools and it will end up stronger than the original. You need to make sure and use an end mill when going into the aluminum. If you use a drill, it will walk off the hardened bolt and into the aluminum and leave you with an oval, which is very not good. I've used this solution on all of the front rotor bolts of my project bike and I have full confidence that it is stronger than the original. This should be easy. I did it with a bridgeport in the shop at work and I was able to do 5 of them in a half hour and I'm a programmer who pretends to be a bad machinist after work...
One more thing, when taking the head off, make sure you don't loose any of the crush washers down into the engine. Trust me, you don't want to do that, it will take you hours to find and you'll need a whole fist full of new gaskets.
Thats not good. My bolt is almost fully drilled out to its own diameter - the drill bit that broke was my second to last up-size. If I were to drill all the way down to where the bit is, do you think it will still walk off?
Options so far:
1. try shatter bit with punch, then finish drilling
2. drill larger hole + helicoil
3. take to machinist
4. replace head
Quote from: dwkfym on May 14, 2009, 10:31:38 AM
Thanks for the advice so far.
Quote from: fred on May 13, 2009, 11:26:26 PM
You don't need an EDM, that would be overkill. It isn't a through hole either, so you'd not only have to find a shop with an EDM, it would have to be a plunge EDM and not the more common wire EDM. You just need a guy with a nice mill who knows how to use it. Just get a machinist to use an end mill to mill out the bolt and a bit of the material around it. Tap the hole, insert a helicoil that matches the thread pitch and diameter of the original header bolt and and get on your way. Easy for someone with the right tools and it will end up stronger than the original. You need to make sure and use an end mill when going into the aluminum. If you use a drill, it will walk off the hardened bolt and into the aluminum and leave you with an oval, which is very not good. I've used this solution on all of the front rotor bolts of my project bike and I have full confidence that it is stronger than the original. This should be easy. I did it with a bridgeport in the shop at work and I was able to do 5 of them in a half hour and I'm a programmer who pretends to be a bad machinist after work...
One more thing, when taking the head off, make sure you don't loose any of the crush washers down into the engine. Trust me, you don't want to do that, it will take you hours to find and you'll need a whole fist full of new gaskets.
Thats not good. My bolt is almost fully drilled out to its own diameter - the drill bit that broke was my second to last up-size. If I were to drill all the way down to where the bit is, do you think it will still walk off?
Options so far:
1. try shatter bit with punch, then finish drilling
2. drill larger hole + helicoil
3. take to machinist
4. replace head
I would go to a machinist. I wouldn't trust a drill not to walk when it hits the broken bit down in there. That steel is so much harder than the surrounding aluminum a drill will probably just walk, no matter what. I think you've done enough work on this head, if I had the kind of luck you've been having, I'd just take it in and get a pro to help you out. It seems like you have done all you can do without actually scrapping the head, so it is best to stop now before you start to break things you really wish you hadn't.
Hell if it's broken off way down in the hole, chase the threads and use a shorter bolt on that one hole. Otherwise it will have to be machined out; the head will have to come off to be set up on the jig bore.