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Cam Sprocket got stuck on timing chain during removal

While trying to remove a cam sprocket it got jammed in the timing chain. At this point the chain is very tight, with just a tiny bit of play. I just have not been able to come up with a way to get enough clearance from the chain to get the sprocket off. I also cannot move the sprocket back onto its position on the cam. And I do not want to turn the crankshaft since much of the left side is assembled, including one of the number 1 rockers. I searched the forums and cannot seem to find anyone posting this problem. Is there someone who knows a way to free this?

A little more info. I am actually assembling the engine and was nearly ready for timing the cams. But I had to remove the right side camshaft housing when a rocker arm shaft for the no. 4 cylinder got stuck while I was trying to install it. That issue is resolved and I was putting the right side back together again when I ran into this new issue. The sad part of this is that I did have the right side sprocket installed this second time around. I was installing the nut to hold it but just a little of the camshaft thread was exposed. I realize now that this is normal, but at the time I was worried something was not in place properly and wanted to remove the sprocket to check on things.

Here are two pictures of the right side where the jam is, and one of the left side. Thanks for your help.



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Old 08-09-2016, 05:21 PM
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Remove the chain guide rail, yes it could damage it but you need some room to give the chain a just enough slack to remove the sprocket.

I just went thru this, I order two just in case D-side was the same way, but it was fine. Just make note of orientation of the guide, longer side toward sprocket
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Last edited by DRACO A5OG; 08-09-2016 at 06:01 PM..
Old 08-09-2016, 05:55 PM
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Looks like the chain is wedged between the housing and sprocket.

I'd gently persuade the sprocket off the cam with a large flat blade screw driver. Go slow and use a thin piece of wood to protect the aluminum case.

I don't know of any other way.
Old 08-10-2016, 10:34 AM
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If the left side is buttoned up, just turn the crank until the bound up link relaxes then turn the crank back again.
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Old 08-10-2016, 01:52 PM
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Thank you all for the replies. I did resolve the problem and am posting this to help anyone facing a similar situation in the future.

Examining the guide rail I noticed that the chain was not even touching it, so I decided to leave it in place. I also tried tugging on the chain some more where it met the sprocket, and came to the conclusion that the chain was just too tight to make any progress that way. So I turned the crank a bit, which created much more free play in the chain. I kept turning the crank (while watching the installed rocker arm on cylinder 1) until the sprocket was completely meshed with the chain again and back in place. I still needed to remove the sprocket though, so I could clean the chain and sprocket of all the wood and metal shavings I created in trying to free this.

I then found an easy way to remove the right side sprocket:
1) Start with the sprocket in its proper position
2) Holding the top portion of the chain in place, turn the top of the sprocket away from the case center (tun clockwise). This puts tension on the top portion of the chain and lets all the slack accumulate in the bottom portion.
3) Jiggle the sprocket to free its bottom portion from the chain. While doing this, ease the bottom of the sprocket away from the camshaft. By keeping all the chain's slack at the bottom and making sure the teeth at the top of the sprocket are still engaged you can free the bottom of the sprocket enough to slip it away from the chain. It took less than a minute to remove it using this method.
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Old 08-10-2016, 03:34 PM
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Outstanding!
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Old 08-10-2016, 09:59 PM
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