Coping with Broken Studs, Bungled Threads, and Busted Bits COLUMN BY NATHAN UNGER Over the years, we all pick up a few ideas regarding broken studs, ‘ bungled threads, and Pe busted bits, and thus di: 7 many of these may be familiar. Yet I hope ; something here will be of some use to someone. Most of these ideas refer to working with steel bolts embedded in aluminum housings. Where did some of these ideas come from? Necessity is the mother of inven- tion. As my brother teasingly put it, “He’s made every mistake that can be made.” Other ideas came from friends and colleagues. Tools you will need: side cutters, vise grip, plenty of sharp right and left hand drill bits of various sizes, impact driver (it twists when hit), dies cut in half, tiny cutting wheel on die grinder, sturdy cen- ter punch with blunt tip, bolt cutter, nut splitter, sharp punch. Also, always use cutting fluid when drilling, tapping or using a die. It goes faster and prevents overheating and dulling of the tip. There are many reasons for tightly threaded fasteners. They might have thread locking compound, corroded aluminum/rusted steel, crossed threads, galled threads, or stripped threads. Sometimes the threads are fine, but the bolt is just really tight. These differ- ences become important as we will see later on. In order to prevent further damage if bolts and nuts resist normal removal, keep in mind the following: ¢ Grab the head of the screw with side cutters held vertically. This allows more grip and force. ¢ Use a bolt cutter or nut splitter to cut the nut. If you are careful, you can preserve the bolt it is on. ¢ Some copper terminal bolts or rotor shafts have seized nuts on them. Shave two sides of a nut off with a cutting wheel (be careful not to touch the bolt threads). Break the nut pieces free. Once you have the hardware off the bolt, use the two halves of a die and rejoin them on the good portion of the threads. Then put your die handle on to work upwards, restoring the dam- aged threads. This is sometimes easier than trying to get a regular die to ‘catch’ in the right way on damaged threads, working down. e With a cutting wheel, cut slots in the bearing or bearing race so that your bearing splitter can grab it. ¢On some Nippondenso alternator brush holder Phillips screws, some- times the Phillips head gets stripped out, and/or the screw is rusted into the regulator or rectifier. Drill counter- clockwise until your drill bit grabs and backs the screw out, or until the head comes off. Sometimes the threads are loose underneath once the tension is off. But if you got the head off the screw, you can disas- semble the alternator and get the broken stud out into the open better. Then use side cutters to grab the stud and turn it out. ¢ Use sharp new Phillips bits. I use a fat handled multidriver to give more leverage for my grip, and I can replace the bits often instead of buy- ing a whole new screwdriver each time. All Phillips bits are not created equal. Some have a different taper to them. I sometimes grind a bit off the tip so the Phillips shape will fully grab instead of the point bottoming out and preventing the screwdriver from engaging properly, causing more screws to strip. ¢ Preheat screws, housings, and bear- ings frozen in housings. Aluminum expands more than steel at a given temperature. ¢ Soak in pail of water. Rust is created in the presence of water, so water will loosen old tight rust. In fact the wet rust is even a kind of a lubricant preventing galling. ¢ Loctite or Permatex will loosen its grip with heat—see your spec sheet. A torch with a built-in igniter saves fuel because it’s only on when you need it. ¢On alternators and starters with Phillips fasteners, clean the gunk out of the Phillips head before attempting removal. Some alternators have the through bolts exposed over the stator— Ford 1G and 2G for example. Cut through these so they will release the housings, but so you have a nice long stud to work with when you are ready to work it free. Can’t get at the one under the long spool with your cutting wheel? Gouge it through with a die grinder bit. All of this is to avoid snapping it off flush with the housing and then having to drill it out. Sometimes if a screw head is dam- aged, cut a slot in the screw with your die grinder. Then use a flat screwdriver on it. This will work on any kind of head, including some broken studs. ¢ Sometimes when working on rusty marine starters, I cut the heads off the starter through bolts rather than risk snapping them off too short inside. Once everything is apart, you can apply heat, penetrant, or whatever, but again, at least you have something to grab onto. Some Bosch alternators have the through bolts sticking right through the back of the housing. Use a thread chaser on these before attempting to remove the screw if those threads look damaged. This will prevent the damaged threads from advancing into the aluminum and galling it. ¢ Often it works to use a sharp punch t