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ENG: Broken Crank Pulley Bolt Extraction

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    ENG: Broken Crank Pulley Bolt Extraction

    Since this has happened to me and now a member on the board, I might as well post this.

    **Note the PICs are in general as I did not take them when I did this.***

    Tools Needed:

    - Drill
    - Bolt Extraction Kit (I got mine at Lowes)
    - Tap Wrench
    - Tap (You may need two, a metric one and a standard one; Later on that)
    - Cutting Fluid (Tap Magic, Rapid Tap, etc.)
    - 33/64 Drill Bit (if the threads are bad)
    - Hole Punch


    - New Crank Pulley Bolt; possibly a 9/16-18 in th same length of the stock crank pulley bolt, along with some washers all Grade 8.
    - New Crank Key (From Honda Dealer; $6)
    - Engine Oil

    **How to do it**

    1- First make a dimple in the center of the broken bolt with the center punch, so the drill bit won't run on you.

    This one you just push down on it and it will punch on it's own. (Harbor Freight)

    2- Take a small bit and start a pilot hole. Take your time and be carefull not to break the drill bit.

    3- Next take the appropriate size drill bit in your bolt extractor kit, and drill into the bolt. Again take your time.

    Use lots of cutting fluid.

    4- I chose to buy the whole extracing set because it comes with both the drill bits and the extractors in different sizes. Plus this wouldn't be the only bolt to break. I was sure of that.

    The Extractor.

    You are now ready to extract the bolt. Insert the bolt extractor and run the drill in reverse...

    and out comes the bolt. (The crank pulley bolt is larger than this.)

    5- Once the bolt is out, check the threads. Clean the threads with the metric tap. Again use plenty of cutting fluid. Run it thru twice until it bottoms out.

    The tap.

    The tap wrench.


    ***If the threads are good go to step 8.*** If not, proceed.

    6- Use a 33/64 drill bit and drill the opening in the crank. Take your time and make it as straight as possible. Use lots of cutting fluid.

    7- Apply lots of cutting fluid to the standard tap. Start slowly and continue until the tap bottoms out. Remove the tap and apply more cutting fluid and run it thru again.

    8- Replace the crank key if it is bent. (you will need to re-do the timing if the key is bent or broken) When you put the new bolt in, be sure to coat it with engine oil and tighten to 159ft.- lbs.

    -Sorry for the bad PICs, but I felt that someone needed this ASAP, so here it is.

    -Hope this helps someone out.

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    Great post. Im in the middle of a timing belt job and I cant get my crank pully bolt off, my friend and I where worried if we broke it it would be a impossible to fix. This will deffinatly help if we do end up snaping the bolt off. Someone who owned my car before me I guess decided to use the RED lock-tite on the bolt.
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