bent crank bolt hole threads

withku

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2010, was attempting to remove my crank pulley when the puller bolt snapped. Managed to get it off, only to find it was threading into the crank bolt threads and ******* them up. Crank bolt won’t go back in, pulley is still stuck. Not sure what to do, help please
 

luigisho

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I don't know this exact setup as I have the older cars but old time attempts we usually used pb blaster or equivalent and soaked the area, gave it time and go back at it. Also a torch (heat the pulley and try to not directly heat the crank so expansion works for you) and a little hammering without damaging the pulley. also while using the puller. You need to see if something can go between the middle bolt and the threaded hole to prevent more damage to threads. Pics might help
 

stripSHO

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Like Luigi said, heat up the pulley to expand it. My torch is the #1 biggest wrench in my garage. I can't tell you the last time I stripped/snapped/twisted a stuck part or fastener, because as soon as I feel excessive resistance I jump straight to either map gas or acetylene to persuade it. And with things like keyless crank pulleys you're dealing with an interference press fit, which means the pulley bore is actually smaller than the shaft unless heated.

Depending on what type of puller you're trying to use they usually have a rotational tip that is supposed to center the jacking bolt as well as keep it out of your threads. If it's missing or whatever then use a socket just smaller than the shaft size and have the puller push into the drive end of it. You should never have to apply so much force to a puller that you snap the (5/8"?) bolt. If that happened then most likely you were using the wrong tool, the wrong procedure, or both! Now I have to wonder if jamming the puller into the crank threads has created a wedge or distortion situation that will make the pulley even more difficult or impossible to remove. Even when it "works" a misused puller can make parts warp, distort, crack, scrape, etc. etc. Maybe you'll be able to clean up the threads with a tap or possibly even bore it out a re-tap it oversized; or maybe the crank is trash and you've just learned an expensive lesson on proper tool usage.
 

luigisho

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I second the socket at the crank shaft hole to keep the threaded hole clean. If it's only a few threads that were distorted you may be able to clean that up. MAPP gas is hotter than propane if you are picking up a small one. I wish you good luck on this.
 

withku

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Like Luigi said, heat up the pulley to expand it. My torch is the #1 biggest wrench in my garage. I can't tell you the last time I stripped/snapped/twisted a stuck part or fastener, because as soon as I feel excessive resistance I jump straight to either map gas or acetylene to persuade it. And with things like keyless crank pulleys you're dealing with an interference press fit, which means the pulley bore is actually smaller than the shaft unless heated.

Depending on what type of puller you're trying to use they usually have a rotational tip that is supposed to center the jacking bolt as well as keep it out of your threads. If it's missing or whatever then use a socket just smaller than the shaft size and have the puller push into the drive end of it. You should never have to apply so much force to a puller that you snap the (5/8"?) bolt. If that happened then most likely you were using the wrong tool, the wrong procedure, or both! Now I have to wonder if jamming the puller into the crank threads has created a wedge or distortion situation that will make the pulley even more difficult or impossible to remove. Even when it "works" a misused puller can make parts warp, distort, crack, scrape, etc. etc. Maybe you'll be able to clean up the threads with a tap or possibly even bore it out a re-tap it oversized; or maybe the crank is trash and you've just learned an expensive lesson on proper tool usage.

I did get the pulley off. I know I ******* that up, I needed an extension, puller bolt was just pushing against pulley.
 

351Blueblood

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Rent this puller from Autozone. Works great.
 

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