# What causes a wobbling pulley? **URL:** \ **Category:** Shift518 Automotive\ **Created:** [April 7, 2009, 3:51pm UTC](https://forums.speedlife.net/t/what-causes-a-wobbling-pulley/243369 "2009-04-07T15:51:57Z")\ **Posts on this page:** 10\ **Page:** 1
**Author:** ![NedZ32](https://yyz2.discourse-cdn.com/flex034/user_avatar/forums.speedlife.net/nedz32/32/6393_2.png) [@NedZ32](https://forums.speedlife.net/u/NedZ32)\ **Post date:** [April 7, 2009, 3:51pm UTC](https://forums.speedlife.net/t/what-causes-a-wobbling-pulley/243369/1 "2009-04-07T15:51:57Z")
A few weeks ago at Gearhead, Pete noticed that one of the pulleys on the Z was wobbling a bit. I think its the AC pulley but idk for sure. When a pulley starts to wobble, is the pulley itself faulty or is it whatever that pulley is attached to? ---
**Author:** ![bennyfizzle](https://yyz2.discourse-cdn.com/flex034/user_avatar/forums.speedlife.net/bennyfizzle/32/6291_2.png) [@bennyfizzle](https://forums.speedlife.net/u/bennyfizzle)\ **Post date:** [April 7, 2009, 4:14pm UTC](https://forums.speedlife.net/t/what-causes-a-wobbling-pulley/243369/2 "2009-04-07T16:14:07Z")
Your a/c compressor pulley? Or is it an idler pulley? Is there anything behind it? like…is it just bolted to the block to keep tension on the belt? ---
**Author:** ![MclarenGP](https://avatars.discourse-cdn.com/v4/letter/m/57b2e6/32.png) [@MclarenGP](https://forums.speedlife.net/u/MclarenGP)\ **Post date:** [April 7, 2009, 4:15pm UTC](https://forums.speedlife.net/t/what-causes-a-wobbling-pulley/243369/3 "2009-04-07T16:15:38Z")
i had a 300z and the crank pull fell right off cuz they keyway snapped. ---
**Author:** ![NedZ32](https://yyz2.discourse-cdn.com/flex034/user_avatar/forums.speedlife.net/nedz32/32/6393_2.png) [@NedZ32](https://forums.speedlife.net/u/NedZ32)\ **Post date:** [April 7, 2009, 4:17pm UTC](https://forums.speedlife.net/t/what-causes-a-wobbling-pulley/243369/4 "2009-04-07T16:17:17Z")
I can’t find a pulley diagram but I’m almost positive its the a/c compressor pulley. Definitely not an idle tensioner though, its one of the accessory pulleys. edit- Its a idler pulley for the A/C system ---
**Author:** ![NedZ32](https://yyz2.discourse-cdn.com/flex034/user_avatar/forums.speedlife.net/nedz32/32/6393_2.png) [@NedZ32](https://forums.speedlife.net/u/NedZ32)\ **Post date:** [April 7, 2009, 5:42pm UTC](https://forums.speedlife.net/t/what-causes-a-wobbling-pulley/243369/5 "2009-04-07T17:42:41Z")
Got it figured out, its a bad bearing in the pulley. Which would also explain the “bad bearing” sound I couldn’t isolate before :lol ---
**Author:** ![kramerbuccs24](https://yyz2.discourse-cdn.com/flex034/user_avatar/forums.speedlife.net/kramerbuccs24/32/6397_2.png) [@kramerbuccs24](https://forums.speedlife.net/u/kramerbuccs24)\ **Post date:** [April 7, 2009, 6:21pm UTC](https://forums.speedlife.net/t/what-causes-a-wobbling-pulley/243369/6 "2009-04-07T18:21:41Z")
two birds with one stone, nice! :lol ---
**Author:** ![NedZ32](https://yyz2.discourse-cdn.com/flex034/user_avatar/forums.speedlife.net/nedz32/32/6393_2.png) [@NedZ32](https://forums.speedlife.net/u/NedZ32)\ **Post date:** [April 7, 2009, 7:12pm UTC](https://forums.speedlife.net/t/what-causes-a-wobbling-pulley/243369/7 "2009-04-07T19:12:46Z")
Definitely, and I need to replace my belts ASAP lol ---
**Author:** ![94Gt5.0](https://yyz2.discourse-cdn.com/flex034/user_avatar/forums.speedlife.net/94gt5.0/32/6377_2.png) [@94Gt5.0](https://forums.speedlife.net/u/94Gt5.0)\ **Post date:** [April 7, 2009, 7:13pm UTC](https://forums.speedlife.net/t/what-causes-a-wobbling-pulley/243369/8 "2009-04-07T19:13:30Z")
Was gonna say bad bearing, but ya beat me to it lol ---
**Author:** ![NedZ32](https://yyz2.discourse-cdn.com/flex034/user_avatar/forums.speedlife.net/nedz32/32/6393_2.png) [@NedZ32](https://forums.speedlife.net/u/NedZ32)\ **Post date:** [April 7, 2009, 7:30pm UTC](https://forums.speedlife.net/t/what-causes-a-wobbling-pulley/243369/9 "2009-04-07T19:30:58Z")
wtf $77 for a tensioner? [http://www.z1motorsports.com/product\_info.php?products\_id=1844&osCsid=1a3546a1b25dc645b919be5c7a4d1b49](http://www.z1motorsports.com/product_info.php?products_id=1844&osCsid=1a3546a1b25dc645b919be5c7a4d1b49) ---
**Author:** ![bennyfizzle](https://yyz2.discourse-cdn.com/flex034/user_avatar/forums.speedlife.net/bennyfizzle/32/6291_2.png) [@bennyfizzle](https://forums.speedlife.net/u/bennyfizzle)\ **Post date:** [April 7, 2009, 8:58pm UTC](https://forums.speedlife.net/t/what-causes-a-wobbling-pulley/243369/10 "2009-04-07T20:58:53Z")
you can always pop the bearing seal off with a pick, clean it out and pack it with fresh grease, sometimes that’s all they need…if it’s wobbling though it’s probably cooked.