bottom idler pulley

Hey guys,
So I found out this morning that my alternator wasn't the only thing making noise under the hood. The lower idler pulley shattered, all that was left was the race, and it absolutely shredded the belt along with it. My question is, I put a new lower pulley on, but it doesn't really sit in line with the crank pulley. It looks like the belt is running on the back half of that idler pulley versus centered (which I think it should be) did I miss something or did something else fly off?

thanks!

Did you replace your alternator as well?

Alternator was replaced last week, idler pulley blew up this morning.

Well I ran into the same problem last week, and I replaced the alternator, tensioner pulley, idler pulley, water pump and belt. After all of that was replaced, it started chewing up my belt, and the belt wasn't centered on the idler pulley. After a bit of investigating, the brand new alternator was out of alignment. On the back of the pulley on the alternator, there are machine washers that the manufacturer uses to put it in line. Well, they had this one all out of line, causing the belt to run on the back of the idler pulley, and then wobble off. So I removed the pulley and added another washer and now it runs great and is in line.

hmm...well it appears that all the other pulleys are lined up, this lower pulley sits about a half inch further forward than the crank pulley. The bolt that holds that pulley in is tight...hold on, I'll go snap a pic of it real quick.

ok, here's the pic, see how the belt isn't centered on the idler pulley?

Wow, thats quite a ways off. I would check to make sure that that is the right pulley, because Autozone gave me the wrong pulley twice. Other than that, I don't know what to tell you. Sorry man.

yeah, that's what I thought, it didn't look right to me. according to oreilly's that's the pulley. Needless to say, im not convinced.

I would take it back and look up the part # on your own and take that to them, unless you have a CarQuest near you, because they always know what I need.

That's what im trying to figure out, everywhere i've looked, the 2 smooth idler pulleys have the same part number....

sorry man

Well went to advance auto and got a different pulley. Opted for the steel vs. plastic. Still fits about the same, the steel one is a touch wider, so i ended up using that. I'm still not 100% that it's right, but since it's deflecting the belt vs the belt wrapping around it, im not quite as concerned.

I used the new plastic one i got earlier and replaced the top idler, truck runs REALLY quiet under the hood now, top idler bearings were going bad as well.

I have the same issue and every pulley I've looked up ( at O'Reilly's, other auto parts stores, and even amazon ) is the same. Everything else is in alignment but that one pulley. My next stop is possibly the shop at a dealer to get this figured out.

It looks upside down to me seriously. The cupping belongs behind and the rounded edge is supposed to be forward

ok so now the pulley mount is stripped out, is it a separate mount or is it part of the engine housing or water pump?

You can just replace the bearings. They are cheap.

DesertWagon said:

You can just replace the bearings. They are cheap.

Click to expand...

Thats what I did, but if he stripped out the mount he has to helicoil or replace the mount now.

soooo.....after much @$#@#%^#^ with my truck. The lower idler pulley and the tentioner mounts are part of the water pump housing on the 5.7 hemi, the lower mount was ruined and i had to replace the water pump. Broke a bolt while putting the pump on so the timing housing had to come off due to where the bolt goes in. After getting everything back together my truck still has a misfire on the number 5-8 witch is where this wonderful ride started. now i find out i might have a broken lifter spring, the lifter might be ceased with in turn could have ruined the cam shaft, well you all see where this is heading. ugh!

Yup..Headers,big cam n tune..

I'm amused, to say the least. The intent of my comment is NOT condescendence. It IS because I've lived this reality many, many, many times in 48 years of professional automotive experience.

The lower pulley failed. Replacement resulted in a tracking problem of the belt.

Law of descending order: "What's the last thing you replaced/ messed with/ adjusted, etc. before the issue/ problem happened?".

The new idler pulley is obviously mis-tracking as evidenced in the photo. I read "Auto Zone" and "O'Reilly's" in all this text. Is that where you bought this replacement part?

Perhaps you might try the dealer? Aftermarket parts have been HUGELY problematic especially these past 9 or so years. First, consider the cataloging of the parts and why this is likely the root here.

Secondly, consider the seeming lack of perspicuity of the person behind the counter who knows NO better than to refer to a computer for info.... no other source.

In case you do not know it, the information in parts catalogs is populated in a series of cubites in a high rise offices in the forest of Keebler trees.

This information's meaning is lost to the transcriptionist(s) due to it appearing to be a form of a lost language.

Reconsider your logic in this and go to a different, yea more accurate source (perceived) such as the dealer for your part. You might just be surprised and you might just learn a lesson about a scourge I've experienced SO many times.