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How many miles after a new timing belt change for the tension check?

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Old 01-15-2019, 08:27 PM
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Yogii
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Default How many miles after a new timing belt change for the tension check?

I have heard after a new timing belt, that the tension should be checked after how many miles?
I have heard a low of 500 miles and A high of 3,000 miles.

What do you guys recommend?

-Yogii
AKA 968 Virgin
Old 01-15-2019, 09:10 PM
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Isaacsracing
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I don't claim to be an expert. In my experience, if it is too tight, the belt whines badly. Because the proper tension is not tight at all, I'm not sure the huge deal in adjusting its tension at all. I've definitely gone back in under that cover 5,000 miles and 10,000 miles later and the tension still looks fine. I also don't go crazy with measuring the tension as is instructed in various threads, etc. Just don't snug it up too much. I'm sure you guys will get on this thread and tell us why I'm wrong!! My way is not very German after all - not precise.
Old 01-15-2019, 11:16 PM
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thomasmryan
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The timing belt is self adjusting on the 968 but the balance belt should be checked after its run in.
​​​​​​​
Old 01-16-2019, 12:18 AM
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Yogii
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Originally Posted by thomasmryan
The timing belt is self adjusting on the 968 but the balance belt should be checked after its run in.
​​​​​​​Which is how many miles?
Old 01-16-2019, 04:41 PM
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RajDatta
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Anywhere from 1000 miles to 1500 miles would allow the BS belt enough time to stretch. Most belts come with a placard to remind you when to re-tension.
Old 01-17-2019, 10:48 PM
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Cloud9...68
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I agree with Isaacsracing on this. In fact, I'll go a step further and call BS on the whole balance shaft belt re-tensioning procedure. The reason I say that is that you can't just go in and turn an adjusting cam and snug it up a little - you have to start from the beginning, and go through the whole procedure of setting the tension and clearances all over again. So you're not really "re-tensioning" it. Also, I had the following experience once. I set the tension slightly too tight after a belt change, in that it would whine when I first started it, but the whine went away after things warmed up. I expected that as the belt stretched, the whine would gradually go away, but it never did, not in the slightest, which leads me to conclude it doesn't actually stretch to any measurable degree after the initial install. I went back in and re-did the tensioning/clearance setting procedure, making sure to leave the belt a little looser, to take care of the whine. I've never again "re-tensioned" the belt after a belt change, and mine is a track car that lives a pretty brutal life.
Old 01-19-2019, 08:18 AM
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regajohn
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The owner's manual / maintenance manual says that between 2,000 and 2,500 miles after belt replacement the belts should be checked for proper tension.
Old 01-19-2019, 11:25 AM
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Yogii
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Thats everybody for their comments. Seems it is not as big a deal as I thought.

-Yogii
AKA 968 Virgin
Old 01-19-2019, 11:49 AM
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Paul Waterloo
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Originally Posted by Cloud9...68
I agree with Isaacsracing on this. In fact, I'll go a step further and call BS on the whole balance shaft belt re-tensioning procedure. The reason I say that is that you can't just go in and turn an adjusting cam and snug it up a little - you have to start from the beginning, and go through the whole procedure of setting the tension and clearances all over again. So you're not really "re-tensioning" it. Also, I had the following experience once. I set the tension slightly too tight after a belt change, in that it would whine when I first started it, but the whine went away after things warmed up. I expected that as the belt stretched, the whine would gradually go away, but it never did, not in the slightest, which leads me to conclude it doesn't actually stretch to any measurable degree after the initial install. I went back in and re-did the tensioning/clearance setting procedure, making sure to leave the belt a little looser, to take care of the whine. I've never again "re-tensioned" the belt after a belt change, and mine is a track car that lives a pretty brutal life.
I think you are spot on....same issue with the timing belt on the Audi A8, had basically the same exact experience.
Old 01-19-2019, 12:22 PM
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Cloud9...68
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Thank you! There is so much folklore surrounding the many procedures associated with maintaining these cars. The balance shaft "re-tensioning" just doesn't make any sense. Maybe back when these cars were new, the belts actually stretched, requiring re-setting the tension, but possibly with better materials available these days, it's no longer an issue.
Old 01-19-2019, 10:36 PM
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Spokayman
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Interesting to read this.
As another point of reference, I had my belts changed last year.
Immediately after the belts were installed the belt(s) were pretty noisy. Worse when cold and less so when warmed up.
Now at 2,000 miles it is still a bit noisy when cold but much less so when warmed up.

Old 01-19-2019, 10:41 PM
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Cloud9...68
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Originally Posted by Spokayman
Interesting to read this.
As another point of reference, I had my belts changed last year.
Immediately after the belts were installed the belt(s) were pretty noisy. Worse when cold and less so when warmed up.
Now at 2,000 miles it is still a bit noisy when cold but much less so when warmed up.

Interesting. That's what I had expected in my case, but the whining when cold never diminished. Do you know what brand belt you use? I've always used Gates.
Old 01-20-2019, 07:47 AM
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Boeing 717
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The guy in this vid at 12:29 says the Dayco belts are supposed to be quieter.

Old 01-20-2019, 12:13 PM
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Yogii
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Love this guys video's! Wish he would do one on a 968.

-Yogii
AKA 968 Virgin
Old 01-20-2019, 01:03 PM
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Boeing 717
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Originally Posted by Yogii
Love this guys video's! Wish he would do one on a 968.

-Yogii
AKA 968 Virgin
I just bought that arnworx belt tension tool and am about to check and set cam timing. Have been watching lots of that stuff lately


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