Idler Part Numbers

[Rpede]

Would appreciate your help. Based on the mark number on my top two idler pulleys I take 16604-31030 pulley for the top two or No. 2 idler pulleys.

These pulleys (top two idler pulleys) have changed from past and now require two different pulley plates: “Inner plate” 16649-310207 and “outer plate” 16659-AD010. Two plates were not used on the superceded factory part.

Question: Do the above referenced pulley plates stack on top of one another? In other words both being in between bolt and face of pulley? Or does one go behind the pulley itself and the other on the outside of the pulley??

The diagrams seem to show both types of pulley plates as being in between the bolt and face of pulley. However this makes no sense to me having both plates stacked on top of each other. Can anyone confirm? Wish I could compare old to new but the part changed and now two pulley plates are used for each of the top two idler pulleys. I am getting different answers from different dealerships to make this even more frustrating.

 

[1000MPH]

I pulled the top #2 pulley from my 2010 to inspect the bearings today. The pulley is easy to get off, use a 14mm deep socket with a breaker bar on the belt tensioner, and a regular 14mm on the pulley bolt. Threads on the idler bolts are normal rotation, lefty loose-y.
The pulley itself and the cover plates were pretty clean with no rust.
The cover plates look like the same part front and back but the parts catalog lists separate part numbers.
Bearings are not as tight as I would like but they are still very smooth rolling. I cleaned up a little sand and dirt and reinstalled. Torque is 40ft-lbs.

 

[Rpede]

Thanks for sharing this! Did you decide to replace any or slap on a new belt? When I changed my 3 idlers I was shocked by how much it quieted overall noise at idle. Wasn’t expecting this because the 3 I removed seemed in good shape.

 

[1000MPH]

The belt is fine, only 26k on it. I might buy the idlers now since prices keep climbing but I won’t replace until they get worse. I was thinking of some quality aftermarket ones but now I’ll probably stick with OEM.
Looks like I can get the #2 for $50 ea and the #1 for $60

 

[1000MPH]

Has anyone pressed the old bearing out of the pulley and install a new one?
Amazon.com: New Koyo Idler Pulley Bearing 6302RMX for Toyota/Lexus Same Day Shipping 6302 RMX : Automotive

 

[DougR]

Has anyone pressed the old bearing out of the pulley and install a new one?

I've always pressed in a new bearing. I'm also curious ... I'll pull out a seal to inspect the balls and races on the old bearing.

 

[1000MPH]

Looks like I’m not going to be able to press the old one out without destroying it.

 

[DougR]

Looks like I’m not going to be able to press the old one out without destroying it.

Lexus and Toyota tensioner pulley bearing replacement - YouTube demonstrates how to replace the bearing. Yes, the old bearings would be damaged when pressed out.

 

[1000MPH]

I ended up buying the OEM idlers using today’s 20% off Toyota sale.
Hard to pass up.
166030P030 $ 46.71 Accessory Drive Belt Idler Pulley
166040P011 $ 41.16 Accessory Drive Belt Idler Pulley

Edit: arrived today.

 

[1000MPH]

Took a pic of a replacement Toyota tensioner assembly that retails for $333. Looks exactly like the Litens for sale on Rock Auto for $100 but could be different bearings.