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Broken Timing Chain? Seems a bit odd to happen.

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YOUR RESEARCHBroken Timing Chain? Seems a bit odd to happen.

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Replace engine now, he will benefit

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Suggestion
The 'supporting hardware' on 997s is significantly beefed up.....and when he replaces his engine now, he will benefit from those improvements
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Broken Timing Chain? Seems a bit odd to happen.

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Leading evidence: 'Replace engine now, he will benefit' (no explicit attributable resolution; this is a reported action or suggestion). Across 1 matching discussions, The most frequently discussed action is 'Replace engine now, he will benefit' (1 discussions). For that action, 0 discussions report a resolution and 0 report an unsuccessful attempt. No action has an explicit, attributable resolution report under the current rules. These are forum reports and suggestions, not a confirmed diagnosis.

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Replace engine now, he will benefit

No successful repair reported for this finding.

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Reported fixes: 0
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Discussions that contain suggestions: 1

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Suggestion
The 'supporting hardware' on 997s is significantly beefed up.....and when he replaces his engine now, he will benefit from those improvements
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Broken Timing Chain? Seems a bit odd to happen.

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POST 1 / ORIGINAL POSTEROriginal post

I've got a buddy that broke his timing chain on his low mileage MY99. No mechanical overruns or other abuse. What do we know about the likely causes of this? Is the timing chain and supporting hardware a possible known weakness of MY99? TIA!

POST 2Original post

Of MY99? Not really..........I think it would be on the general list for M96....not high on the list, but there......(and long after 99). The 'supporting hardware' on 997s is significantly beefed up.....and when he replaces his engine now, he will benefit from those improvements

POST 3Original post

Dell, you sure the chains didn't just come off after the end of the intermediate shaft came off? That's a 'more likely' failure on a MY99

POST 4Original post

usually the chains break due to something getting between the gears and the chain some thing else likley failed and debris got caught in the chain. Not to common but i have seen it

POST 5 / ORIGINAL POSTEROriginal post

Not quite sure the specifics of it. Just asking the question for a friend that will read this thread but not as a member of the site. Just doing a favor for him. Thanks for the input everybody. I am sure you have helped him tremendously.

POST 6Original post

Isnt there 3 of them? 1 from the crank to the intermediate shaft and then 2 from the intermediate shaft to the cams? Which one let go?

POST 7Original post

actualy on a 99 there are 5 chains crank to ims ims to cam x2 cam to cam x2 most likely is one fo the ims to cam chains

POST 8Original post

i only know it was a weakness in BMW 3 series...needed to exchange it every 30K miles...once I didn't and it snapped at 40K miles.....lucky for in I was standing still...the mechanic told me your pistons will push thru your engine

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