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Can you actually tell if you need a new timing belt by looking at it?

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Old 02-17-2005, 08:08 PM
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stoked944
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Unhappy Can you actually tell if you need a new timing belt by looking at it?

I know there is a way to do a timing belt check, but i don't know when it was changed last changed. So would checking it even do any good? I should probably just get it done don't you think?
Old 02-17-2005, 08:09 PM
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Dave951M
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Are you going to risk bent valves over a $15 part?
Old 02-17-2005, 08:16 PM
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PCA 944
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I have a similiar dillemma. I bought my 944 nearly a year ago, but its had a broken odometer for at least a year with the previous owner. While I am nearly certian it was rarely driven (the po had a 98' 911), I don't want to risk distroying the engine for a "15 dollar part."

Would the timing belt condition degrade even if the car is rarely (once a week, and only to get engine warm) driven, or not driven at all?
Old 02-17-2005, 08:19 PM
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Kelly Chiu
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yes rubber is dries out and cracks over time... even if its not exposed to UV rays.
Old 02-17-2005, 08:29 PM
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Dave951M
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Yes, time is one of the big enemies of the timing belt, pun intended. The fabled "time capsule" car is a time bomb of seals, belts and hoses that are way past any rational intended service life. Most of the service interval recommendations on timing belts that I've seen are usually XX000miles OR X years. If you do your own work, this is a $70 job (timing and balance shaft belts). You might want to take the same path we did building race cars, when in doubt, throw it out.
Old 02-17-2005, 08:30 PM
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No
Old 02-17-2005, 08:39 PM
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zoxx2004
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I was told every 40,000 at first,but unless its a daily driver you will not reach that for a long time.Several porsche machanics told me every 5 years.I just changed mine it had 40,000 -looked perfect.after I changed it, I realized that the tensioner was all the way extended.With no adjustment left-- not good.I do track my car.I will stick to 5 years. ( this is only my experience)
Old 02-17-2005, 08:57 PM
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Mike C.
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No, no, no!
Old 02-17-2005, 08:59 PM
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Exactly. I'd say a visual inspection is better than nothing but not as good as a retensioning, which is not as good as a replacement. If anything looks bad as part of a visual inspection, change it immediately.

Since by the time a belt visually LOOKS bad it's already compromised in terms of its strength I'd say a bad looking belt is a guarantee it's bad, but a good looking belt is not a guarantee it's good.
Old 02-17-2005, 09:52 PM
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Burma Shave
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If you don't know when or how many miles...do it now. Belt,seals,rollers and waterpump. Do it yourself. $400 or so in parts. I did mine when I first bought it. Take your time(weekend). Great way to get to know your car and not that difficult with some patience and planning.
Old 02-17-2005, 09:54 PM
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Mike C.
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I second that Burma Shave...
Old 02-17-2005, 10:15 PM
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jinx099
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How do you change the belt without changing the valve timing? My belt has about 4k miles and 9 months on it according to the PO, but he also said the last one broke prematurely.
Old 02-17-2005, 10:28 PM
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Serge944
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Worn belts will have a glazed look.
Old 02-17-2005, 10:32 PM
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KLR
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Can you actually tell if you need a new timing belt by looking at it?

Yes -- if it has cracks, missing teeth, glazing, etc.

Can you tell if you DON'T need a new timing belt by looking at it?

No. Therein lies the rub.
Old 02-17-2005, 11:06 PM
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theedge
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Originally Posted by jinx099
How do you change the belt without changing the valve timing? My belt has about 4k miles and 9 months on it according to the PO, but he also said the last one broke prematurely.
Clarks garage has a how-to, with pics.

To answer your question, theres several spots through the whole system where they are lined up to certain reference points, and as long as it all stays there and is lined up in the same spots on re-assembly, the timing stays the same.


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