Lower idler pulley replacement

update, Just wanted to update folks that i'm still using the original bolt and so far so good I have not seen any issues. I was able to
find a longer bolt in ebay that would fit but decided not to buy and use it yet.

 

The OEM bolt is M10 x 1.50R, 37mm long ("R" for reverse thread). The bolt with the 36174 Gates pulley is 50mm long, but can't fit it as it is not reverse thread. After adjusting for backspacing and bearing width the bolt length you want if using the 36174 pulley to replace the tensioner pulley is 45mm, reverse thread. Don't know the bolt grade but it can be either 8.8 or 10.9.

After looking at the tensioner pulley bearing carefully, it appears the inserted bearing is a 5203, measuring 17x40x17.5 . I ordered a Naichi 5203 2NSL and will report back if it works.

Edit: pitch in reverse thread bolt is actually 1.5.

 

The Nachi bearing, #5203-2NS was a direct fit for the tensioner pulley bearing. Replacing the bearings in the other pulleys is more of a challenge as they appear to use proprietary sized inner races. I could not locate them anywhere. The sizes are 10x42x13 for the PS and Alt idler pulleys; and 10x42x26 for the AC idler pulley. It appears I can fit 15x42x13 bearings by inserting a 15mm - 10mm bushing and using two bearings for the AC idler pulley. I have ordered the parts I think I will need and will post a how-to if it all comes together.

Here is a pic of the tensioner pulley with the new bearing pressed in. I bought a 40mm outer race ($5) to push in the new bearing. You can probably use the old bearing but I didn't want to risk damaging the new bearing as you don't want to put any pressure on the inside race as you press it in.

 

Bump.

@Chuy The above bearings, for the tensioner pulley, is that the easiest way to go about replacing the pulley? vs replacing the entire tensioner assembly? My tensioner pulley is squealing and I was going to replace the whole assembly, but I know its a PITA with the alternator and ac compressor. if I can get away with removing the pulley from the tensioner itself and just pressing in a new bearing, I'd rather do that.

anything else I should look out for?

@MrCrowntown

 

this thread makes my head hurt. I have the same chirp for about 30 seconds when i first start my truck in the morning, developed about 2 weeks after replacing the belt.

 

I ordered the tensioner assembly. attempting to replace this weekend. the addition of boost only makes this job harder.. I swear its a love/hate relationship.

 

Yes, replacing the bearing in the tensioner pulley is much easier than replacing the assembly. Just make sure the assembly is not damaged and doesn't need replacing to begin with; it likely will not as the tensioners use an internal spring to maintain tension and the springs are pretty sturdy.

Once you remove the bolt holding the pulley (turn clockwise to remove), the pulley slides right out. Then, it's just a matter of removing the bearing and pressing a good quality bearing back in. I'll be doing this on the wife's Lexus; looks like it's tensioner may use the same model bearing as the Taco.

 

https://m.youtube.com/watch?v=v1yV-...e6v4VICSYwReYbED6R9Y8iFSnNdlQh7ADYYwdn-kMiM8Q

anyone's bad pulley ever sound like this??

I believe it's either idler #2 or tensioner

 

Kinda sounds like a busted bearing - hopefully, it's not the AC bearing. Remove the belt and check each pulley for play; don't forget to check AC, Alternator and PS bearings. On my V6 Taco, it was the #1 idler bearing (next to the AC) and the tensioner pulley bearing that had play. But replaced the bearings in all three idler pulleys (and tensioner pulley bearing) to start fresh.

 

I replaced my idler 1 already because I thought it was that one for sure. When I spray idler #2 next to the ps pulley it does stop for a few days. I'm betting it's that!

I was worried it was the water pump or crank pulley

 

spraying, generally, only checks for belt squealing. The bearings are protected with a wide washer and they are sealed for water proofing. I suppose if the seals are shot, you can get water in there. I'd just replace them all and keep the good ones as backups. You can just replace the bearings and save yourself some $$. I made a thread for that: https://www.tacomaworld.com/threads...arings-in-the-idler-tensioner-pulleys.480961/

 

Hmmm ok. I ordered the entire assembly, but maybe I'll order just the bearing and try that first. I'll check that write-up you posted for part #'s. Thanks man.

@MrCrowntown

 

I was able to find the tensioner pulley bearing at a local bearing supply warehouse for about $25. Saved me the shipping and didn't have to wait several days.

Alternate part # - 3203-2RS (multiple brands use this part number)
To reiterate, you are looking for a two row angular contact, fully sealed bearing. 17 OD x 40 ID x 17.5 Width

Keep in mind the tensioner pulley bolt is reverse threaded.