Broken gas tank bolts

Damn, I broke off the head on the bolt that holds the tank to the frame. Anyone have any ideas how to get out the broken piece. Do I need to drill out very carefully that piece and re-do the threads?????? I know I should have used the torque wrench.... Hindsight is 20/20


The most common method is to use a screw extractor, or "easy-out". These you can find pretty much anyplace that sells automotive tools.

The process is generally to carefully center punch the broken bolt as near on center as possible, then drill into it with a drill size recommended for the tool. The extractor is inserted into the hole you drilled, and as you rotate it counterclockwise, it jams in place and backs out the broken stub. DO NOT break the easy-out off! They're far too hard to drill out.

In cases where the bolt was broken only because it was over tightened, the threads may still be in pretty good shape. You can sometimes get lucky and run the bolt out by using a left hand twist drill bit, which you deliberately try to "stick" in the bolt so the drill runs the bolt out. This requires a reversible drill, obviously. If you can get to the inboard end of the broken bolt by going through the other side, you may be able to catch a normal right handed bit in it and have the same result.

If you are extremely lucky, it may back out for you by pushing on it with a pencil eraser and turning the pencil to back it out a ways. Worth a try.

Good luck.

Did it break right at the head of the bolt, or flush with where it goes into the frame? If it broke right under the head, pull the 2 bolts that hold the mount to the tank, remove the tank and slide the mount off, and use a pair of vise-grips to grab what's left of the bolt and remove it. If it's broke flush with the frame, see grayracer's post. A left-handed drill bit is a good start, if it doesn't work, at least you have a hole drilled to use a screw-extractor on.

Well let's just say that I have another bolt now.... It broke right in half!!! I have never had this problem before and all of the sudden it snapped. I know that the bolt was not even in all the way. The bolt was feeding correctly also. Well, thanks all for the input!!!!!!

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