Posted by Gordon Maney on Saturday, August 02, 2003 at 6:11PM :
In Reply to: Broken Stud - help needed posted by Mark in NW OR on Saturday, August 02, 2003 at 3:48PM :
The entire time you are studying it, keep putting penetrating oil on that stud. Who cares if it is drooling down the front of the engine. Kroil is the best that I have found, but you probably don't have it. So.... get some WD-40, some CRC, or some Liquid Wrench, or all of them. You can always use that stuff later, anyway. Also, use a flat ended drift punch, do a little rat tat tat on the end of the stud. Not enough to peen and expand the end, but enough to shock it a bit. Anything you can do to change the relationship of that stud with the tapped hole is to your advantage. If it was a casting you could heat with a torch, you would, but given your location, that would be problematic and also very risky. Don?t do that.
In 37 years of doing this kind of work, I have had few instances where screw extractors of any sort could resolve the problem. You will, in all probability, end up drilling it out and tapping new threads.
Have someone watch the angle of your drill when you start to drill, because it is easy for an inexperienced person to think they are square with the surface but actually not be square. Practice the angle at which you will be drilling. Go ahead, laugh, but this is a critical moment here. You will wander off axis if you are at the wrong angle. You can?t tilt the drill and change your direction once you are in the moving hole. Start with a small, new bit. Initially just establish your beginning spot. Stop and look at it. I have had times when I used a small diameter, flat ended punch to smooth my inaccurately located starting spot and made a new one. Look, look, look, think, think, think.
If you really tear it up in the drilling, you will need to put a thread repair insert in it. Don? t use a Heli-coil (registered trademark); those are like a spring. Use the kind that is effectively a tube or sleeve that has threads inside and out. If you have to go to the next thread size bigger, you can drill out the hole in your water pump.
You are experiencing a mechanic?s nightmare. But, just think of the character you are developing....
Follow Ups: