for those who have the dreaded valve cover knocking sound...
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Joined: Apr 2010
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From: Bay Area, CA
E55 AMG, 72' Toyota Carina, 63' Ford F100, 72' Mercedes 250c, 15' Harley Davidson Softail
for those who have the dreaded valve cover knocking sound...
Check your Idler pulleys! For the past month I've had an extremely horrid knocking sound which I swore was coming from under the passenger side valve cover. Now we all know how loud our engines are normally, but this sounded like there was a loose bolt inside the valve cover grinding away. It would go away as the revs went up but on idle the noise was unbearable. Anyways, my Indy shop is usually backed up a week or so so i decided to do some investigatng and found that my s/c idler pulley had a slight wobble to it. Upon removing the belt, the wobble was pretty damn significant. I hopped on eBay, ordered a $3 6203zz bearing, replaced the bearing inside the pulley and what do you know...no more knocking!
Just want to point out as well, there was absolutely no other symptoms besides the noise. The car still pulled like normal and drove the same. Of you're experiencing other issues it may infact be valvetrain issues.
Lastly. Many thanks to pearlpower for the awesome DIY, literally saved me a couple hundred $$$ and a bunch of sleepless nights.
Just want to point out as well, there was absolutely no other symptoms besides the noise. The car still pulled like normal and drove the same. Of you're experiencing other issues it may infact be valvetrain issues.
Lastly. Many thanks to pearlpower for the awesome DIY, literally saved me a couple hundred $$$ and a bunch of sleepless nights.
Last edited by AMG_RL; Jul 14, 2012 at 12:11 PM.
Thread Starter
Super Member
Joined: Apr 2010
Posts: 781
Likes: 0
From: Bay Area, CA
E55 AMG, 72' Toyota Carina, 63' Ford F100, 72' Mercedes 250c, 15' Harley Davidson Softail
This is the one I used: http://www.ebay.com/itm/130692941606...84.m1497.l2649
Thread Starter
Super Member
Joined: Apr 2010
Posts: 781
Likes: 0
From: Bay Area, CA
E55 AMG, 72' Toyota Carina, 63' Ford F100, 72' Mercedes 250c, 15' Harley Davidson Softail
Yes just one, the serpentine belt pulley's bearing isn't replaceable. Here's the DIY also https://mbworld.org/forums/w211-amg/...ng-repair.html
