Lawn mower blade bolt broke off

Old 04-23-18, 12:41 PM
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Lawn mower blade bolt broke off

I have a John Deere Z425 zero-turn mower. I was mowing today and the bolt holding one of the blades sheared off so half the bolt is still stuck in the threads. Any idea how I go about removing the rest of that bolt?

Thanks in advance!
Old 04-23-18, 01:05 PM
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I would suggest that you try a product such as EZ Out Damaged Screw Extractor. Below is a link to it on Amazon.
Old 04-23-18, 01:39 PM
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Is there any part of it sticking out ? You may be able to grab the bolt with Vise Grips.
Old 04-23-18, 10:39 PM
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If it's up in the hole, it's probably going to be more work to get it out than you want to exert. I would try a left hand drill bit and see if it even offers to turn while drilling. If not, it might be easier to just replace the jackshaft.
Old 04-24-18, 09:02 AM
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I've seen photos and videos of using a TIG welder to weld a nut onto an exposed bolt, and using a wrench to remove the bolt. On a bolt broken flush to the surface, another video showed using a TIG welder to build up metal high enough to grab using vice grips to remove the bolt- but you have to be careful not to weld the bolt permanently into place.

Absent a TIG welder, if the bolt is big enough the left-handed drill bit idea could hollow out the bolt enough to get an "e-z out" bolt extractor into place. Tap it in with a hammer and the left handed flutes catch the sides and hopefully allow you to remove the bolt with a wrench. This set is about $10.

Good luck with it, let us know how it goes!
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Old 04-24-18, 11:26 AM
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I would be with cheese on this one. You could remove the shaft and try a repair, but they are usually cheap enough to replace and be done with it...albeit you do have that dirty JD name on it so
Old 04-24-18, 01:39 PM
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I'm speculating that the bolt broke off when the blade hit something really, really solid and so it is in there now just about as tight as it can be.

I hope you can remove the Spindle/Quill Assembly from the deck and work with the EZ Out on a bench . . . . or get a new blade mount for the Quill Assembly. Maybe fix this one at your leisure and then save it for a spare.

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