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Discussion Starter #1
I've been tearing into my Saab 93 after trying to re-torque the head bolts with no success, I'd say I'm far from familiar with this motor. I managed to get the head off and everything to TDC, Just curious. It seems as if someone along it's life has changed the timing chain and all looks very good, my question is can I change the head gasket without doing the timing at this very moment? I do plan to do it but at the moment I do not have a lift or the time to fight doing it with the motor in the car. Any help would be greatly appreciated.
 

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There's no reason to pre-emptively replace a timing chain. If it was properly lined up and the tensioner wasn't overextended (before you took the head off) then there's nothing further to do.
 

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You definitely don't have to replace the timing chain. It's a huge job to remove and reseal the timing cover, which is the usual, but not only, way to gain access to the chain. LIke Jvanabra says, if the timing chain tensioner isn't overextended, then don't worry about the chain. I replaced the head gasket on my 1997 900 some number of years ago, but left the chain alone. Just be careful when taking off the head and putting it back on. The chain guides extend up into the head. One of them pivots so that the head can come on and off, but if the chain is allowed to fall down between the two guides, it pushes them apart, and the pivoting one can no longer pivot and will probably break when the head hits it. I used one of my wife's elastic hair ties to hold the guides together, which keeps the chain from bunching up between the guides. Another method is to have a helper hold the chain up while you remove the head.
 

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Discussion Starter #4
You definitely don't have to replace the timing chain. It's a huge job to remove and reseal the timing cover, which is the usual, but not only, way to gain access to the chain. LIke Jvanabra says, if the timing chain tensioner isn't overextended, then don't worry about the chain. I replaced the head gasket on my 1997 900 some number of years ago, but left the chain alone. Just be careful when taking off the head and putting it back on. The chain guides extend up into the head. One of them pivots so that the head can come on and off, but if the chain is allowed to fall down between the two guides, it pushes them apart, and the pivoting one can no longer pivot and will probably break when the head hits it. I used one of my wife's elastic hair ties to hold the guides together, which keeps the chain from bunching up between the guides. Another method is to have a helper hold the chain up while you remove the head.
Being an amateur i did not look at the tensioner to see if it was over extended. I also believe that I let the chain fall into the timing cover so I will have to fish it back out. I bought the car from my cousin who was very meticulous with it and he claimed to never have any issues other than the head gasket.
 

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At least it's easy to fish out the timing chain. Sometimes it will get a little stuck, but if you pull up on it while turning the crankshaft a tiny bit, it will come unstuck.
 

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If I'm not mistaken, if you have not turned the crankshaft (timing chain) the tensioner should still be at the same place it was when it was running. It doesn't just pop out when tension is taken up off it - otherwise you would not be able to pull it and check the wear. It should still be where it last was when the motor ran. But, let one of the other guys who's worked the motor internals confirm that for you.

You'll need a 27mm socket to remove it. It's on the back side of the engine under the manifold.
 

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Bob , once the head is removed the timing chain tensioner is extended .
To be able to check (measure ) the tensioner there is a small bolt that is removed from the head of the tensioner , before removing the tensioner assembly via the 27mm hex. This bolt houses the internal spring that operates on the foot of the tensioner and provides the ability for the pawl to extend as the chain wears .

If you remove the tensioner assembly without removing this spring tension , then the tensioner will continue to extend to maximum extension , likewise if you have lifted the head from the block .
By removing the spring first the tensioner will remain in the position that it had been last operating in , via small ratchet indentations in the leg of the tensioner .
 

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To the OP , as said by Jvan not mandatory to replace any timing gear . If it inspects ok leave well enough alone , its too late to measure the tensioner , so just do visual inspections of the Guides , top sprockets and chain and take your time getting the timing correct (TDC) on reassembly .
 

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Bob , once the head is removed the timing chain tensioner is extended .
To be able to check (measure ) the tensioner there is a small bolt that is removed from the head of the tensioner , before removing the tensioner assembly via the 27mm hex. This bolt houses the internal spring that operates on the foot of the tensioner and provides the ability for the pawl to extend as the chain wears .

If you remove the tensioner assembly without removing this spring tension , then the tensioner will continue to extend to maximum extension , likewise if you have lifted the head from the block .
By removing the spring first the tensioner will remain in the position that it had been last operating in , via small ratchet indentations in the leg of the tensioner .
Thanks, makes sense.
 

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Discussion Starter #10
If I'm not mistaken, if you have not turned the crankshaft (timing chain) the tensioner should still be at the same place it was when it was running. It doesn't just pop out when tension is taken up off it - otherwise you would not be able to pull it and check the wear. It should still be where it last was when the motor ran. But, let one of the other guys who's worked the motor internals confirm that for you.

You'll need a 27mm socket to remove it. It's on the back side of the engine under the manifold.
Well as it turns out the tensioner has a good line across the leg where you can visually see how far out it has been extended due to the oil staining. I'd say its got another 5 or so clicks until it has reached its limit. I will be doing this soon I am just saving to pay someone to do it.
 
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