Help, camshaft/timing chain question



8 replies to this topic
  • Glen_T

Posted December 16, 2001 - 05:30 PM

#1

I hate it when things come apart and don't go back together. Some time ago I replaced my top end. The new head gasket was bad or I screwed up the installation. Anyway when I went to replace it I got everything back together, but I can't get the timeing chain over the cam sprockets. I remember it being a bit of a challenge before, but now they won't go. I can't see anything holding the chain up, but maybe it is doubled up on the crank gear. I've removed the spring adjuster, so I know that is not the problem. If I remove the flywheel, will I have access to the chain on the crank? Anyone have a suggestion? Am I missing something? Thanks for any advice you all can give.
GLEN

  • Adam

Posted December 16, 2001 - 07:57 PM

#2

Check to see it your chain dampers (black rods) move freely u could have tightend your head on one and that not leaving enough slack for the chain

  • Boit

Posted December 16, 2001 - 10:38 PM

#3

The DOHC design takes some patience when it comes to timing and re-timing this valve train. From your description, it appears that you need to time your cams in relation to the crank. Check your manual for this procedure.

  • Boit

Posted December 16, 2001 - 10:54 PM

#4

I apologize for my ambiguity. When it came to timing these cams, what worked for me is this. Initially, I made a small scribe mark on the cam chain plate directly above the tooth that lined up above the intake and exhaust TDC. This allowed me to time both cams simultaneously without searching for a timing mark. As long as you initially make this mark and proceed with your cam timing, you won't have to worry about getting out of time. Clear as mud?

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  • Glen_T

Posted December 17, 2001 - 06:00 AM

#5

Hi Boit and Adam, Thanks for the response. Timing the beast isn't the problem, Getting the chain over the cams is. Adam, I know there is slack on the adjusting chain guide, but I'll have to check the forward chain guide. That could be the problem. What I really think the problem is is that the chan got a little loose around the crank gear and is now doubled over on itself somehow. I'll look these things over and let you know, and if anyone else has an idea, please post.
THANKS!

  • Hick

Posted December 17, 2001 - 01:18 PM

#6

I bet you have an extra link stuck on the crank gear, just that little bit would be plenty to make the chain too short to reinstall. This happened to me once and the only way I was able to get it straightened out was by removing the flywheel and then unkinking the chain under the crank gear.

Unless you keep good tension on the chain it can and will skip a tooth on one side of the crank gear.

Hope this helps.

  • Squidwerd_on_a_400f

Posted December 17, 2001 - 03:35 PM

#7

First, make sure the cams are free, meaning not bolted down yet. I then put the chain over the exhaust cam, then lean your intake cams slightly forward (toward you) and push the chain over the cam sprocket with your finger. I've done it a few times already with much success. I hope this works for you. :)

  • Hick

Posted December 17, 2001 - 03:47 PM

#8

I forgot to add that if you do indeed have an extra link under the crank putting a kink in the chain there you need to unbolt the lower chain guide to straighten it out, which is why you must remove the flywheel.

The metal portion of the guide holds the chain on the gear and you normally wouldn't be able to pull the extra link past it.

But as Squid points out, the chain will never fit over both gears if you try to install it with the cams in place on the head. Install the chain, check the timing, then put the caps on.

Hope this helps.

  • Glen_T

Posted December 18, 2001 - 06:10 AM

#9

Thanks Hick and Squid.
I've been creating finals this week so I haven't been able to get back to working on the monster. Hick, I think you hit the nail on the head of the problem. My dilema now is how to get the flywheel off with out a holding tool or air ratchet. I tried a strap wrench, but it didn't offer enough grip. I guess I'll have to make something to do the job.





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