opened the valve covers: broken chain guides .. and all 4 of them too!! The chain was intact. The only thing I don't get is this thing got new guides and chain back in 1997- 15-20 k miles ago. Why the failure?

Regards

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a2


1978 280 CE silver
1986 560 SL black
1987 300 SDL cream
1994 SL 500 brilliant green
1997 E 300d dessert silver
2005 FORD F250 Superduty Crew cab 4x4

____ADMU____