Idler Pulleys / Tensioner Pulley / Serpentine Belt

I doubt the bearings are the same size. The oem bearing size is 17X40X17.5 - bearing types 5203-2NS, 5203-2NSL, and 5203-2RS will fit. I put a Nachi 5203-2NS bearing in my oem tensioner pulley and it is coming up on 150K miles.

 

So ordered the Ebay bearing and belt kit with Koyo bearings and Dayco belt . Downloaded WBA app and 2 of the bearing came back Koyo and 1 couldn't scan . Noticed the 2 the checked out good has the QR code and the one that couldn't scan just the bar code . Was $72 shipped

 

So after looking @Chuy other thread the 6302rmx was only the sealed bearing so ... Dont know if bearing was pressed in a new pully and put in the bearing box since scan as good .
But just going keep just in case .Ended up my bearing was good just routed belt wrong . Ran belt between PS pump and water pump ynder idler pully and belt snapped after 10000mi . Pully had rubber built up inline with groves in belt . Me

 

@hemitruk I looked into the JTEKT company. The Japanese company formed upon the merger of Toyo Seiko (of Toyo Bearings) and Toyoda Machine Works in 2006. In 2009 JTEKT acquired the needle roller bearing division of Timken. Toyoda acquired Torsen in 2003, so Torsen is now part of JTEKT. So, JTEKT makes bearings but I was unable to find a legit catalog of them selling pulley/bearing units. I found several Chinese sites with them.

https://www.prnewswire.com/news-rel...-acquisition-of-timken-division-80706827.html

This link shows the change in the legit box design, from Koyo only, to JTEKT/Koyo.
https://koyo.jtekt.co.jp/en/2023/02/news20230201.html

 

Thanks for info . Yea box looks a little different put checked out as good on WBA app . I also looked on supposed Koyo jtek site and it listed it as tension earing . Bottom line I guess is to pick up from known distributors . Going keep set I brough if I need in future because idler pulls easy to change if it doesn't last . Tensioner will be buying oem or gates . Thanks for all your research .

 

Great. Thanks for the guidance. I'll pick up the Nachi 5203-2NS.

 

The terms “rotational drag” and “normal” in the same sentence was what I was hoping for. Thank you, Chuy.

 

This is exactly how my original belt looked! On the other end of it was another separation about 3” long. Glad I replaced it! Got to do the bearing in my #2 idler next to P/S pump. That was the only one that seemed urgent.

 

Just did the bearing in my #2 idler. Used "KOYO 6302 RMX for Toyota 4.0 Engine Idler Pulley Bearing 10x42x13 mm" on ebay from RODAVICTORIAUSA, https://www.ebay.com/itm/166510779851 .

I don't have a press at home so I used my vise. The pulley was pretty rusty (I live in Maine). As I was pushing out the bearing it came in stages. But it snapped to each stage and I thought that I had broken the vise!

Once it was out I cleaned up the pulley and pressed in the new bearing. Went pretty smooth.

 

Make sure that it didn’t take out the front main seal…..that happened to me

 

Not sure what you mean? What would have happened to the main seal and how?

 

When my belt did the same it got caught behind the harmonic balancer and ruined the seal

 

Got it. No, it was all where it was supposed to be, just didn’t know that it had separated.