Ad Widget



No announcement yet.

Broken Header Bolt removal

  • Filter
  • Time
  • Show
Clear All
new posts

  • Broken Header Bolt removal

    So when I switched my exhaust back to stock, one of my header bolts snapped off. It snapped off with maybe 3-4 mm sticking out. However I most likely can't get a hold of that littleness. So I started drilling, dead centre. Took me for ever, but now there is a drilled hole 1cm in. It is probably half of the diameter of the bolt. I stopped it at that. What should I do now? I have a set of 5 screw extractors, but i will need a very small socket size (one that is not common) to be able have some force. any suggestions?
    1989 Suzuki Katana 750

  • #2
    well, I would have tried a small pair of vise grips before drilling, but since you've already drilled, I doubt a screw extractor will work. The header bolts usually are installed with locktite. I'd say your best best is to drill until you hit htreads and then retap the hole. thats usually what you end up doing in locktite applications. If your gonna try the extractor, take a map gas torch and heat that bad boy up first, that may give you the edge and it might break loose.


    • #3
      Did you use Loctite when you installed the aftermarket header? How long was it on before you went back to the stock header?

      If it is just corrosion holding the bolt in place I would try soaking it down with a penetrating solvent. I really like Gibbs oil. I have also been told that PB Buster is awesome. You may want to let it soak overnight before you try to work the bolt out. Once you did that often a couple good hits from a hammer where the bolt head was will help loosen the bolt. You could use a punch to drive the bolt around. Another option is to use a Dremel to cut a screw driver flat.

      If the bolt was installed with Loctite a torch will burn it up.


      • #4
        Screw extractors are meant to be used with Tap handles. These are "T" handles with adjustable jaws for holding square (Or I guess hex) shafts.
        For this a cheapo one will work.

        As a preemptive strike, use several of the above suggestions. heat and penatrating oil.


        • #5
          penetrating oil
          coupe hammer whacks
          more oil
          whack again, try and turn
          heat, more oil, more whacking

          If this doesn't work you can try extractors or if you can find a small left hand drill bit, sometimes this will work.

          This may end with a heli coil
          I became insane, with long intervals of horrible sanity. -- Edgar Allan Poe


          • #6
            Just make sure thatwhen you heat it you heat around the bolt and not the bolt itself.
            PM me for Ultrasonic Carb Cleaning, pilot screw o-rings and washers and mercury refills

            Harley Davidson
            The most efficient way to turn gasoline into noise without the biproduct of horsepower


            • #7
              You usually don't use loctite on exhaust header bolts because of the heat they get exposed to; they're supposed to be coated with a bit of anti-seize paste instead (exactly the opposite stuff!).

              Heat, oil, heat, oil, patience, oil, and pray.
              If you still have a stub sticking out, it helps a lot, because it gives you something to grip tightly (vice-grips set to extreme pressure works well, along with a drift hammer to smack it loose). Once it starts rotating just a bit, the rest will come easy. Or you can cut a slot in the end, treat it like a flat-head screw and use an impact driver.

              Good Luck!
              =-= The CyberPoet
              Remember The CyberPoet


              • #8
                I have busted a number of bolts in in my life, and they are all a pita. I did discover one thing,,,in my humble opinion....oil, wd-40...or any of that other crap does not amount to crap on a busted of bolt in a hole. I mean think about it....if it is seized so tight that it won't even budge, how do you expect enough oil to get in there to help? penetrating my butt. Oil is only really effective on a bolt with a nut and and you want lube to bring the nut off over the threads. So add all the oil you want...all you are going to do is make a smelly mess with potentially harmful fumes once you heat it up. Plus I believe your bolt angles slightly upward...doesn't make for good penetration anyway.
                Try "shocking" it. that has always been my most successful way.
                1- drill your hole in the center like you did.
                2- Take a small fine flame blow torch and heat directly on the bolt itself...heat it from the center outward. Don't go crazy on the in don't turn the engine itself red.
                3- toss ice cold water on it. It will have the same effect as tossing a red hot piece of cast iron into cold will crack. The bolt wont crack, but the crap holding it will.
                4- tap in your extractor and put some steady pressure on it.

                Best results using an extractor is to have 2 extractors. One for right handed for left handed. Sometimes you have to use the "loosen/tighten" approach....turn it both directions.

                If all that fails, do what arsenic said....drill it out an re-tap it. I also find that a good lock on the extractor with vise-grips give you a bit more leverage than the t-handle. I know UFO said not to heat the bolt itself, but it has worked for me in the past. Try all the other suggestions and save mine for last if none work. Then drill/re-tap if it doesn't work.
                I don't have a short temper. I just have a quick reaction to bullshit.


                • #9
                  Thanks for all the helpful tips!

                  I did use penetrating oil before I started anything, and I was knocking it with a punching before I drilled. I used about 5 or 6 applications of the oil, however I didn't heat it up yet. I tried looking for reverse drills, but failed in all the stores I went in. Im wondering about the extreme heat to cold affect. Sounds like it would work. A friend of mine also has an impact driver which I can take advantage of (although it isn't very good). Thankfully I am a patient kind of guy

                  thanks again.
                  1989 Suzuki Katana 750


                  • #10
                    I did that same thing w/ yamaha.. I tried everything u tried to get it out.. finally I took to a local bike shop and he drilled it out for me, and retapped it..was fine then, but man , what a PITA !!


                    • #11
                      So far all I did was drill the starting hole, I didn't attempt to take the bolt out. Im just prepping, planning out my strategy for battle.
                      1989 Suzuki Katana 750


                      • #12
                        Oop...forgot to mention one other that has worked for me. I once broke off a 1/2 inch bolt, so I drilled and tapped a 1/4 left hand thread and screwed a left hand thread 1/4 in bolt into it....tightened it up and cranked out the 1/2 bolt after heating it up. But I was working in a machine shop and had access to this stuff.
                        I don't have a short temper. I just have a quick reaction to bullshit.