Author Topic: chain rattle only in the rain  (Read 2237 times)

Berlin

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chain rattle only in the rain
« on: March 10, 2011, 10:50:56 AM »
Hi guys. I have a strange prob. It is a very loud timing chain rattle/noise but it only happens on humid days particularly if it rains. Otherwise there is little to no noise from that area on dry days. What do u think is the correlation? Thx,alex

DesktopDave

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chain rattle only in the rain
« Reply #1 on: March 10, 2011, 05:31:18 PM »
That's an odd one.  If/when was the chain tensioner upgraded?  Given the reputation of the M42's cam drive I'd be mighty tempted to pull the chain covers and take a good look.

Might also be a weak valve adjuster, but that'd be a tapping, not a chain rattle.  Cold days take a little longer to get oil into a leaky TC tensioner.
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Berlin

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chain rattle only in the rain
« Reply #2 on: March 11, 2011, 04:48:40 PM »
hi thank u... the chain might be original one, now at 204km, the tensioner was changed at 185km.
the rattle doesnt seem to depend on temperature as ive driven it on -15c days that were dry and no noise...just when RH is >95% seemingly... thoughts appreciated