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ok so i was installing my water pump and in the process one of the long bolts broke and now im screwed and have a piece of bolt in my block, if this ever happened to anyone could you please help thanks:cursing:

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Yes, I've dealt with this many times.


1. If you can get vice grips on it (use a quality pair like genuine Vice-Grips brand), clamp it tight enough and usually the bolt will unscrew.


2. If you can't get vice-grips on it, sometimes with a hacksaw you can cut a small slot in it, and use a flat screwdrive to unscrew it.


3. Or slowly, slowly tap it counterclockwise with a a center punch to unscrew it. Takes forever patience but often works.



But if the bolts is broken down in the part, those methods don't work. These will:


4. Easiest way: You can drill a small hole right into the bolt stub and use an "easy out" to remove it. Sears sells these as do the auto parts stores.


5. Sometimes even though the bolt is broke off in the part, you can still get the part off. My worst case was on a Chevy Luv (Isuzu engine) a head bolt broke on me. I was eventually able to wiggle the head enough to move it up 1/8 inch. I stuck a hacksaw between the head and block and cut the bolt off. After that the stub of bolt unscrewed with my fingers!

Edited by ggzilla
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I snapped off a crank cap bolt on a 350 before due to a torque wrench that was all buggered up. Easy out ended up snapping off trying to get it out :mad:

ended up dropping the block off at a machine shop and they got it out somehow :blink:

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  • 2 weeks later...

if you resort to easy-outs, be careful cos they can break. ive had two break on me which only made the problem worse :(


helps if you drill the pilot hole bang on dead center so be patient and get that hole right the first time. hard though i know, usually not a lot of room to whack a drill in there

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Here is some advice from a machinist. If it is broken flush with the surface of the block, try to locate the exact center of the broken bolt. Start with a small center punch and make a small indention. Measure again and be sure the mark is in the center. Now is the time to move the center punch mark in the direction that it needs to go to get it in center. Once you are sure it is centered, you can use a larger center punch and then use a starter drill or "center drilll" to get a good starter hole or pilot hole with a starter chamfer. Try to get a set of left handed drill bits and use the drill bit that is just under the "tap drill" size for the bolt. Use a left handed drill bit with your drill motor in "reverse" and if you are lucky, and the bolt is not "bottomed out", the bit may grab and back the bolt out before the drill goes all the way through. If it doesn't you now have a hole to try the largest size eze-out that will work in the hole. Be careful with the eze out because if you break one of these hard things off in there, then you will never drill it out. The only way to get an eze-out is with a carbide drill bit or arc gouger. Try to put some heat on the broken bolt after you get your pilot hole (as much heat as the block will stand without damage. Last but not leaste before you resort to the heli-coil, try to drill the pilot hole out to the "tap drill" size (measure with dial calipers the inside of one of the tappped holes to see what size the tap drill was). Once the hole is drill out to tap drill size, then all that should be left of the broken bolt is just the threads, and they will peel out from top to bottom, if you can get hold of the top of the starting thread. Good luck! Dan

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I forgot to add, after you get the broken bolt out, be sure and run a taper tap and then a "bottom" tap in to clean up the threads. Blow out the shavings with compressed air and "never-sieze" your bolts before installing your pump. Dan

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