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Old 12-14-2008, 12:03 PM   #15
DisTech OP
Studly Adventurer
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Joined: Sep 2008
Location: Seattle
Oddometer: 616
Broken Exhaust Header bolt

Step 1: Break exhaust header bolt while attempting to remove exhaust.
Step 2: Attempt to remove the rest of the bolt sticking out of the head with vise grips! Optimal results are a red face and a smooth slightly conical shaped stud that make vice grips shoot off (similar to trying to squeeze a watermelon seed (in reverse)).
Step 3: Buy the cheapest "easy out" bolt extractor kit you can find.
Step 4: Attempt to drill the center of the broken bolt. This part went surprisingly well and I was getting my hopes up.
Step 5: The easy out is basically a reverse threaded tap. So the theory is that as you tighten the easy out in the loosening direction of the stuck bolt, the bolt will eventually unscrew. A nice theory, but since you bought the cheapest extractor kit you could find this is what happens. You get the easy out started and at about 3ft/lbs it breaks off in your broken bolt.
Step 6: Learn about tap disintegrators.

Step 7: Try and find a local machine shop that knows what a tap disintegrator is. Favorite responses.
  • a very long pause (with whispering in the background), no.
  • I hate being disintegrated (in the best Marvin the Martian voice summonable on short notice).
  • They make those? Where do you get em?.
Step 8: Send the head to a state where they have tap disintegrators and perform tap removal for a reasonable fee. I used Jerry's Broken Drill and Tap Removal. The head should be back on Tuesday.

The Art of Extraction gives a great explanation (annealing vs hardening) on how to use heat to help get broken bolts out. I decided against using heat because I wasn't sure what that might do to my aluminum head, but Manley's recommendation for brass or stainless steel on exhaust lead me to looking for the DR650 stainless steel bolt kit.

I had also found several references while Googling to bolt removal using various kinds of acid. My favorite is this one,
"I don't know where to get it, but nitric acid will eat the steel bolt and not touch the aluminum. It will also eat flesh, lungs, clothes and the like." This reference also contains a couple reasons why I didn't try this method.

Originally Posted by Richard_A
another option for bolt extraction , weld a nut on the busted bolt , then soak the crap out of it with some PB Blaster , it should then break free , too late for that now huh
Yes indeed! That could (should) have been Step 2. I don't have the means to weld anything myself so I would have had to take it to a shop, but the local shops could have done that faster and cheaper. Ahh, hindsight.
DisTech - Suzuki (1993 DR350S & 1994 DR350, 1996 DR650/DR790), BMW (1999 R1100GS)

DisTech screwed with this post 12-14-2008 at 05:27 PM Reason: Richard_A
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