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Discussion Starter #1
Hello again, fellow Alfisti!
So I've encountered a new problem on my head gasket replace odyssey.

It seems that the timing chain is now too short! A bit of background..
earlier today I decided to bring the engine back to TDC, it wasn't exactly there when i pulled the head(don't ask)...anyhow I turned the crank with the timing chain disconnected to TDC. I did this by putting the car in gear and pushing it from behind. What I failed to noticed immediately, is that the timing chain was winding itself around the idler gear. As soon as O noted that i was able to gently unwind it by turning the alternator bolt. No damage seen..
I now have the engine exactly at the P mark and the cams at the journal marks.Perfect right?
I have been trying to reattach the timing chain and it is about 1/4'' too short! The tensioner is fully disengaged, and the chain seems fine, no slack. *** am I missing? Im almost ready to start her up!
Help, or aiutto per favore!
 

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I believe, as you had to turn the engine backwards to unwind the chain from the idler pulley, you now have slack on what should be the non-tensioner side of the timing chain.

I would carefully turn the exhaust cam backwards taking up this slack, ensuring the engine does not turn, and then re-time it. Note I might have the wrong camshaft but I think it would be the exhaust cam ...
Pete
 

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Sorry to hear your having trouble.

You must have slack somewhere in the chain. Could be a bit on either side of the lower sprocket or the usual, on the exhaust side, but you have slack somewhere.

I would try to re thread the chain.

You will get it.

Vin
 

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Discussion Starter #4
Thanks for the reply Pete. How can I turn the cam? Can I snake out the chain and reinstall?

BTW how would turning the cam accomplish anything? Its not connected to anything. The chain is still detached.

I cant see any slack..I must have misunderstood you.
 

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What happens is that three chain links get caught on just two bottom sprocket teeth, thereby "Shortening" the chain when you try to install the master link. If this happens to me, I loosen the wires holding the chain ends and poke around the bottom sprocket with a long wood stick or rod and manipulate the chain links so they fit the teeth on the sprocket. Not a big deal, but sometimes takes a little patience.

...I cant see any slack..I must have misunderstood you.
 

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I have been trying to reattach the timing chain and it is about 1/4'' too short! The tensioner is fully disengaged,
What does "tensioner is fully disengaged" mean? At this point it should be all the way toward the intake side with its spring fully compressed. You get it to that position by prying it with a piece of wood or large screwdriver while loosening the lock bolt. Of course, re-tighten the bolt once the tensioner is all the way in.

If "disengaged" means its bolt has been loosened and the tensioner has moved toward the exhaust side of the engine, then yea, the chain will seem too short.
 

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It can happen that the chain slips off of the intermediary gear, and re-seats on one row of gear teeth. This is an imperfect seating that takes up a little bit of chain length. Use a flashlight and inspect down both sides to see if the chain is resting where it belongs on the gear. Easy to fix.
 

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Discussion Starter #8
okay gents,
I've dropped the chain several times and rethreaded it. It still is exactly the same! No closer or further.This is very strange. Is it possible that during the winding I broke a link? If I remove the lower pan, will I be able to reach the lower gear that holds the timing chain?
I am running short of patience. Any suggestions?
 

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Discussion Starter #9
What does "tensioner is fully disengaged" mean? At this point it should be all the way toward the intake side with its spring fully compressed. You get it to that position by prying it with a piece of wood or large screwdriver while loosening the lock bolt. Of course, re-tighten the bolt once the tensioner is all the way in.

If "disengaged" means its bolt has been loosened and the tensioner has moved toward the exhaust side of the engine, then yea, the chain will seem too short.
Hi Jay, to answer your question, yes the spring in the tensioner is fully compressed and taking up NO extra slack. thats the 1st thing I looked at too! I cant seem to figure this 'simple' thing out!
 

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okay gents,
I've dropped the chain several times and rethreaded it. It still is exactly the same! No closer or further.This is very strange. Is it possible that during the winding I broke a link? If I remove the lower pan, will I be able to reach the lower gear that holds the timing chain?
I am running short of patience. Any suggestions?
The left side guide gear can make it difficult to see and adjust the fit of the chain around the bottom of the intermediary gear. I predict this is where your problem is. It can be solved by fiddling with the chain from the top. You'll need good light to see the details around the intermediary gear.

The power to break off a link would require a huge breaker bar, and almost certainly do other damage as well.

Is the adjustable tensioner fully butted up to the aluminum head, or is there visible some of the tensioner shaft? If the latter, the securing wedge may have come loose and fallen behind the tensioner, keeping it from fully retracting.
 

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Discussion Starter #11
This is beyond crazy! I have just finished rethreading it again. Basically i let the exhaust side of the chain fall into the block and pulled the intake side almost all the way up. Then i pulled the exhaust side up slowly and trying to ensure that the slack was taken up and that the chain fit the lower gear. Guess what? The space between the two ends is exactly the same! I am not sure what to do next.
DP3-yes the tensioner is fully 'in'. These cars drive me nuts!

Anyone?
 

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Hi Jay, to answer your question, yes the spring in the tensioner is fully compressed and taking up NO extra slack.
If that's the case and if there are no kinks in the chain (as DPeterson3 discussed above) then I suspect that your cams are positioned in such a way that the tension side of the chain (the exhaust side) isn't fully tight. This is why I usually remove the bolts-nuts securing the cam sprockets to the cams and loosen the large nuts on the end of the camshafts - that allows the cam sprockets to fall where they need to to allow the chain to fit with the cams lined up at TDC.

Do you have a cam turning tool? If not, this stuff is tough to work on. But if so, turn the exhaust cam slightly CW (standing in front of the engine), install the chain on it, and then turn it back CCW till the marks line up. Did that gain you a link between the cams?
 

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Discussion Starter #13 (Edited)
If that's the case and if there are no kinks in the chain (as DPeterson3 discussed above) then I suspect that your cams are positioned in such a way that the tension side of the chain (the exhaust side) isn't fully tight. This is why I usually remove the bolts-nuts securing the cam sprockets to the cams and loosen the large nuts on the end of the camshafts - that allows the cam sprockets to fall where they need to to allow the chain to fit with the cams lined up at TDC.

Do you have a cam turning tool? If not, this stuff is tough to work on. But if so, turn the exhaust cam slightly CW (standing in front of the engine), install the chain on it, and then turn it back CCW till the marks line up. Did that gain you a link between the cams?
Jay-no to the tool. In Bradens 'bible' he uses a vise grip and thick leather to turn the cams.
Ill try and attach some pictures
 

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Looks like slack in bottom pic ,

...from the bottom sprocket to the tensioner
 

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Jay-no to the tool. In Bradens 'bible' he uses a vise grip and thick leather to turn the cams.
Ill try and attach some pictures
Yup, your pictures show just what I am struggling to describe in words: there's visible slack on the tensioner side because the sprockets on the cams don't align with where the chain links want to go. Your choices to fix this are:

- Rotate the cams till the chain drops onto the cam sprockets with no slack on either side. Then the master link will fit. Hopefully the cams will end up properly timed when everything is buttoned up, though as I wrote earlier, they may not due to head milling, different thickness head gasket, or cams not timed right previously.

- Disconnect the cam sprockets from the cams as I described previously. Then it's simple to get the chain to drop onto the sprockets. Release the tensioner, rotate the cams to their alignment marks, and re-install the vernier bolts.
 

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Tensioner needs to get out !

Do I misunderstand something ?
Tensioner isn´t even 1mm released ! Chain must be loose with that; do tighten the chain properly. What does this have to do with cams or cam sprockets ? It´s just about the tensioner.
 

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Thanks for the reply Pete. How can I turn the cam? Can I snake out the chain and reinstall?

BTW how would turning the cam accomplish anything? Its not connected to anything. The chain is still detached.

I cant see any slack..I must have misunderstood you.
Sorry, I thought you had the chain on the cams and we're trying to join the chain in the middle of the cams.
Pete
 

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Do I misunderstand something ?
Tensioner isn´t even 1mm released ! Chain must be loose with that; do tighten the chain properly. What does this have to do with cams or cam sprockets ? It´s just about the tensioner.
Hunt.

Please read the above quote. It is difficult to understand what you are trying to say.

Your picture shows slack between the intermediary gear and the tensioner. Yes, your tensioner is fully retracted. No worries on that point.

What would be your solution about the slack between the intermediary gear and the tensioner? Might this be where your missing chain-length is?

1. Rotate the intake cam slight backward with the chain pulled out to disengage it from the teeth.

2. When the chain drops into the new position on the teeth, rotate the cam forward to tighten the chain between the cam gear/tensioner/intermediary gear.

3. Do the two ends now come close enough to insert the master link?

4. If not, using whatever you are using to turn the cams (I use a big wrench on the nut), slightly rotate the exhaust cam backward to remove slack on that side. Make sure the intake cam is rotated forward as far as it will go to remove the slack on that side.

5. Do the ends meet now?

6. If they do, then check the cam-to-bearing marks to see if they are in time. If not, you are either off one tooth on one or both of the cams, or you will need to loosen the nuts and set bolt to adjust for correct timing. Don't loosen the bolts just yet.

7. If the cam to bearing marks ARE in line except the intake cam is slightly advanced, then fasten the master link, and loosen the tensioner. Use your wrench (or whatever) to move the intake cam backwards to let the tensioner remove the slack between the cam/tensioner/intermediary gear. Is the intake cam mark now aligned with the bearing journal mark?

Let us know what you find after doing the above.
 

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Sorry I haven't read every post here but have you made mention here of the fact, as mentioned in your other thread, that you dropped a cam journal cap washer into the timing chain area and don't know where it is?
 
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