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Broken Dowel Pin

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Old 03-26-2009, 03:34 PM
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Thumbs down Broken Dowel Pin
Brought my cam to a shop to have the dowel pin removed and it broke off. The owner said it needed to be drilled out now with a cobalt bit. After it broke I didn't want him to go any further and I took the cam home. This is why I try to do everything myself. It's a Comp Cams 280XFI. Anyone have any suggestions for getting this pin out now without destroying the cam?
Last edited by Mystery Bird; 03-26-2009 at 03:41 PM. Reason: add info
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Old 03-26-2009, 03:54 PM
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I would have a competent machine shop remove it.
I am curious. Why did you want it removed?
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Old 03-26-2009, 04:06 PM
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Probably to go to a different length pin.
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Old 03-26-2009, 05:01 PM
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Originally Posted by MeanGreen97Z
Probably to go to a different length pin.
Perhaps, but from my limited experience, LT1 engines require a much shorter pin length over other SBC applications. I have had to grind them down, not put a longer one in.
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Old 03-26-2009, 05:09 PM
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Originally Posted by Don 97 SS
Perhaps, but from my limited experience, LT1 engines require a much shorter pin length over other SBC applications. I have had to grind them down, not put a longer one in.
Vented opti setups require a .700" long dowel pin, non-vented setups requires a .300" long dowel pin.
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Old 03-27-2009, 06:07 AM
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I had to remove it because it was too short.
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Old 03-27-2009, 08:03 AM
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Originally Posted by Mystery Bird
I had to remove it because it was too short.
Mystry Bird, that is most interesting. From my research when I did cam swaps, GMPP specifically recommended a dowel length of .620 and Dynaspark recommended a max of .605. How short was yours?
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Old 03-27-2009, 10:09 AM
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I believe it was somewhere in the .400 range probably for the earlier Opti's, I have a 1995 so I need the longer one.
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Old 03-27-2009, 01:48 PM
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im looking for ideas for removing/replacing this pin as well. The machine shop i took it to was unable to remove the old pin by heating it up and tried a few different things but didnt want to risk messing it up by drilling so im open to ideas.
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Old 03-27-2009, 02:08 PM
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Originally Posted by z28maro
im looking for ideas for removing/replacing this pin as well. The machine shop i took it to was unable to remove the old pin by heating it up and tried a few different things but didnt want to risk messing it up by drilling so im open to ideas.
I pray they didn't take a torch to it.
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Old 04-01-2009, 11:47 AM
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Decided this weekend I'm going to give the drive it out from the back a try. I will post with results.
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Old 06-03-2009, 04:36 PM
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So I just couldn't get it out. I ended up taking a depth gauge and measuring it from behind and realized it was a very small piece left in there. So, I pounded it in from the front all the way and installed new pin.
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Old 06-03-2009, 07:17 PM
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They come right out with a slide hammer, don't see what the big problem was for them
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Old 06-04-2009, 01:45 PM
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Interesting - this guy said he had a brand new comp cams cam break the dowel pin too:
https://www.camaroz28.com/forums/sho...d.php?t=690898
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Old 06-04-2009, 04:36 PM
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My buddies machine shop has a special tool they use to burn out broken taps and stuff like that using spark erosion - it's a kind of EDM - wonder if it would work for busted dowl pins?
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