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Hi. Perhaps this is a silly question but...

It's that time of the year, checking the 1990 C900 before taking it for its MOT, and realised the timing chain needs replacing. I found one I bought last year - febi bilstein -but appear to have misled the masterlink (oops!). So my question is does anyone knows if its possible,(used to be for motorbike chains) to buy a master link on its own?
Cheers.
 

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I wouldn't do that. The chain is not meant to have a master link although I'm sure it may be possible. I for one wouldn't trust it inside my engine. The chain is meant to be riveted over when joining. There are plenty of threads on this.

You say it's time for replacing the timing chain. Why do you say this and how do you know? They are good for at least 150k miles, and even then I would measure the tensioner extension to make sure. http://www.saabcentral.com/techhelp/c900/timing_chain.php
It won't fail an MOT on a timing chain.
 

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Discussion Starter · #3 ·
I wouldn't do that. The chain is not meant to have a master link although I'm sure it may be possible. I for one wouldn't trust it inside my engine. The chain is meant to be riveted over when joining. There are plenty of threads on this. You say it's time for replacing the timing chain. Why do you say this and how do you know? They are good for at least 150k miles, and even then I would measure the tensioner extension to make sure. http://www.saabcentral.com/techhelp/...ming_chain.php
It won't fail an MOT on a timing chain.
Thank you for the advice. The thing is, though, this chain comes new open with a master link. It comes from an online saab specialist. I used one of a similar type last year - in an older 8v C900, following instructions from townsendimports.com - and as yet have not had any trouble with it.

I'm aware the state of the chain is not part of the MOT, but I just checked the tensioner, which is out by about 12mm, which, according to my manual, is 1mm too far and an indicator that the chain needs replacing. The car has done 176K.
 

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replacement joined chains are available now as you are aware(you have one lol), but a riveted one is better.
It does make for easier changing/joining,though, I still have the originals in mine at 176k.
If you have done it before and it's OK go for it, it's very rare to have a chain go anyway, and I think the purists prefer the riveted link, as at one time that's all you could get, but I would'nt imagine they would still be trying to sell them if they failed,or were not very good(eg did'nt last/wore easily??) as it would have been on the forums before now
 

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Wasn't there a thread on here of someone who incorrectly peened the end of the link on his chain it gave way and valve damage occurred. It was fairly recently IIRC.

Master link chains work fine, they use them all the time in motorcycle engines. They're fine as long as you orient them correctly and don't bend the link doing it.
 

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I'm sure the master link is available online. Just Google it if you can determine the size. Why did you separate the link from the chain?:nono; I know they are used extensively in car engines (MB) and bikes, but I wouldn't be happy with it. It may be easier to just to source another riveted in-situ chain. http://www.partsforsaabs.com/default.php?cPath=105_118
I know what you mean, with an 8v it's not so much of a worry though lol ;)

I still put an endless chain in there because I was pulling the TC anyway.

How does someone DIY peen it though - sufficiently and safely enough so that it doesn't fail? I vaguely recall seeing a link somewhere?
 

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A properly installed master link should not be a problem. As a motorcycle rider (among other things) I have found chain issues other than stretching are related to installing the lock backwards. The closed end of the lock should always go toward the rotation direction. Peening rivets can be an art, and if you are not used to the concept (not saying you have to be experienced, just very familiar with your goal and what is the WRONG way to do it), can be a problem.
 

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A properly installed master link should not be a problem. As a motorcycle rider (among other things) I have found chain issues other than stretching are related to installing the lock backwards.
Motorcycle chains don't rotate at 5500 RPM. At least mine never has.
I wouldn't trust a Master Link on any Timing Chain, the consequences of failure are too great.
I've replaced dozens of them, and seen a hundred done, with never a hint of failure using the SAAB Special Tool made for riveting the chain. I Mickey Moused a few too, but you need to be careful doing so.
 

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Motorcycle chains don't rotate at 5500 RPM. At least mine never has.
I wouldn't trust a Master Link on any Timing Chain, the consequences of failure are too great.
I've replaced dozens of them, and seen a hundred done, with never a hint of failure using the SAAB Special Tool made for riveting the chain. I Mickey Moused a few too, but you need to be careful doing so.
Haven't been around the latest generation of go karts, have you? Besides, RPM is not the speed of the chain, we need to get to FT(M)/Sec speed to evaluate. RPM is the rotational speed and the sprocket size at the crank will be the determining sprocket. If they can handle 150+HP at the contact patch and 200+ speeds, linked chains can't be all that bad if of recent manufacture. I also note Jim you mention the special tool. Most folks out there either don't rivet as part of their job, or keep rivet setting tools handy. I just happen to be one of those oddballs who do.
 

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RPM is the rotational speed and the sprocket size at the crank will be the determining sprocket.
I agree, but the Crankshaft gear does turn at 5500 rpm with a chainwheel diameter of about 3 inches. That's a lot more demanding than any Motorcycle I've ridden. I wouldn't try to run 150 horsepower through an itty-bitty timing chain either.



I've seen many broken chains on the 1985 to about 1990 models, many of them breaking around 120k. Later models with the Japanese rather than German chain are more durable. If your 1991 model has 250k on the original chain, that's normal, but don't advise owners of earlier models that they needn't worry. Some people had them break while they were stopped at a red light. If you just roll in a new chain on those models, they're as good as the later ones. 15 years ago, a broken chain would cost $1500 to fix; it may cost more now.
 

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I agree, but the Crankshaft gear does turn at 5500 rpm with a chainwheel diameter of about 3 inches. That's a lot more demanding than any Motorcycle I've ridden.
This is exactly the bit I would be worried about. 5.5k around a 2.5" pitch sprocket at the crankshaft end and with rapidly varying load. Considering the damage that can ensue on failure, rather your engine than mine. Masterlink? No thanks.
 

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I wouldn't try to source the master link by itself, as there are simply too many variables involved. I did try once, and you'd think Canada being a metric country would have made it easier, but the American influence is too great, and metric anything (let alone chain links) are near impossible to find in a general purpose application. Also, IWIS has a decent reputation for their chains, and going with anything else is just scary. Weakest link and all, right? The entire chain is like $30, I'd just replace the whole thing.

3 years ago, I replaced and peened my own master link chain, having researched how it's done. A year later, when I was rebuilding my engine, I decided I didn't want to chance it and replaced the whole thing again with an endless chain. That's how confident I was in the job. As crwchf01 said, peening a link can be an art...heck knows the amount of work it took with regular tools (hammer, vice grips, screw driver, wrenches) to get the peen to something I was happy enough with, and even then, I didn't have peace of mind. I'm not saying it's worth the extra work that would be required to put in an endless chain, but I did it since the whole thing was apart anyhow. That said, apart from the peening, rolling in a new masterlink chain was relatively easy.

li Arc
 

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I had 3 Alfas back in the 70's & 80's and they all had master links in the chain and the routinely saw 6000 rpm . Never had a problem with it.
 

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I'm not sure I understand why a correctly installed master link would be more prone to failure than a peened over pin. There were plenty of times I jumped hard on all 160rwhp of my Ducati SS at places like Loudon and honestly, the master link was the last thing I was worrying about :confused:
 

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I had 3 Alfas back in the 70's & 80's and they all had master links in the chain....
Yet they don't do it that way anymore. Nobody does it that way anymore. Time marches on.

Huge slow-moving motorcycle chains are not analagous.
Next to straight-cut gears, I think chains are the most efficient method of power transmission, but they have speed limitations.
Do they use master links on turbines? Why not?
 

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No, they sure don't use chains on turbines. I'd guess they turn way faster (and produce a lot more heat too) than anything we're talking about. I'd like to see the "Einstein chalkboard" comparison between the stress load transfer to the chain of a 15t final drive gear on a 160hp motorcycle to the one put onto a timing chain. Not doubting anything here in this thread...just curious and always fascinated at the math/engineering.

Ps: 100% in agreement...I love chain drives if just for the weight savings over a series of gears
 

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