I am looking for an LSJ idler pulley and I can't seem to find a new unit anywhere. I can find the tensioner pulley easy but can't seem to find the idler pulley anywhere. I am going to give CED a call today and see if they can be of any help. Has anyone ever bought the pulley new anywhere or do they just not seem to ever go out in general?

 

if i recall right its the same as the tensioner pulley.

 

Shows one in the same to me on my system. (Independent autoparts owner)

 

Thanks a lot guys. It appears they must be the same. I will report back if I find out differently.

 

So my suspicions of the idler pulley being on it's way out was confirmed today. 6 mile round trip and it went from clean to looking like this. Now I just have to determine if the idler pulley bearing or me having the tensioner too tight was to blame. I have a LSJ tensioner pulley that is supposed to arrive today from Rock Auto so I will know for sure if it is the same as the idler pulley tonight.

 

Carnage




My idler pulley completely destroyed itself. The tensioner pulley has the same internal diameter as this idler pulley. But the casing of the new pulley rubs slightly on the idler pulley arm. It seems close but does rub. The remnants of the old pulley does look like it has a different casing configuration. The idler pulley itself doesn't seem to be listed anywhere. I could try to make the tensioner pulley work but with what's left of the old pulley I can't even confirm the outer diameter.

new tensioner pulley ACDELCO

Idler pulley bracket part number is 12584364

 

Alright I think I figured out what is going on. It appears the old pulley design had a slot on both sides for a dust cap. It looks like the back side of the idler pulley arm has a rib on it that is made to fit in this old design idler pulley. There is a warning on the box of the new pulley that says this design doesn't require a dust cap and to ensure proper clearance. You may be able to see in the picture of my last post that the new pulley does not have this slot.
I popped my dust cap off my existing tensioner pulley and took a picture so you could see the slot I am talking about. I measured the slot on the pulley and they do line up with the rib on the idler pulley bracket.

Here you can see the rib on the idler pulley bracket that I referenced earlier. I can either try to find an old style pulley or just machine this rib down.


I'll probably end up just machining the housing down depending on what shows up at the local Car Quest today. I would assume there are some older design pulleys that still have this groove but I don't have the external dust cap that goes on the outside so it wouldn't be protected like it should be. I might just swap the pulley off of the tensioner to the idler. I tried to get the bolt of this morning but it seemed really tight but now that i think of it iirc that bolt that goes in ZZP's adjustable tensioner is actually left hand thread.

 

Machined the lip on the idler pulley bracket down so I can now use any tensioner pulley regardless of style

FYI there are idler/tensioner pulleys you can still get that have the groove in them if you run into this issue and don't want to machine your bracket. You just have to be careful when ordering because there typically isn't any indication of this that I can tell. Sometimes the picture can be misleading too like on Rock Auto the ACDELCO pulley shows a picture of the old style with groove but the actual pulley did not have the groove.

 

Forget everything I said comparing new pulley design to old. While this change is accurate it turns out that the tensioner pulley is actually not the same pulley that that the idler assembly uses. The idler pulley actually has a bigger outside diameter. The bearing ID is the same but the pulley overall is bigger.
Might be hard to see in the picture but the idler pulley definitely has an bigger outside diameter

Only numbers I can find on idler pulley is >PA66-GF25< and F-550070.01-0300.