serp belt popping noise

[UncleLDP]

Ok, quick little problem and could use some help. My serpentine belt is slightly coming off the alternator pulley and making a popping noise when it "pops" back on. I'm waiting for a new bearing to be delivered today. I'll try that first.
My question is; are there any adjustments that can be made to either of the pulleys that can align the belt?
FYI-I replaced the alt 4 months ago using OEM. New belt then.
Any thoughts would be appreciated.

 

[Mike NXP]

Ok, quick little problem and could use some help. My serpentine belt is slightly coming off the alternator pulley and making a popping noise when it "pops" back on. I'm waiting for a new bearing to be delivered today. I'll try that first.
My question is; are there any adjustments that can be made to either of the pulleys that can align the belt?
FYI-I replaced the alt 4 months ago using OEM. New belt then.
Any thoughts would be appreciated.

No adjustments can be made on our accessory belt / pulleys. The tensioner is hydraulic and adjusts to apply the correct amount of pressure and all of the pulleys should be aligned by default

>> Belt popping off the alternator that was recently replaced. Hmm, makes me think you need to look over the install to make sure its all seated correctly...They make fancy laser tools for checking pulley alignment but there's no reason they should be out of alignment unless something if failing/broke/not installed right

- Are you sure you are using the correct belt
- Does your idler / tensioner assembly feel good? plenty of tension / not binding up
- Are you sure the noise you are hearing is the belt popping on/off the alternator pulley . Can you post a video?

 

[UncleLDP]

No adjustments can be made on our accessory belt / pulleys. The tensioner is hydraulic and adjusts to apply the correct amount of pressure and all of the pulleys should be aligned by default

>> Belt popping off the alternator that was recently replaced. Hmm, makes me think you need to look over the install to make sure its all seated correctly...They make fancy laser tools for checking pulley alignment but there's no reason they should be out of alignment unless something if failing/broke/not installed right

- Are you sure you are using the correct belt
- Does your idler / tensioner assembly feel good? plenty of tension / not binding up
- Are you sure the noise you are hearing is the belt popping on/off the alternator pulley . Can you post a video?

Thanks Mike. Yes, correct belt. Tensioner seems to be leaning outward a bit (that's why I was asking about any adjustment that I may not know about) and that's also why I'm replacing the bearing first. Yes,100% sure the pop is being caused by the belt popping back on the alt pulley. I'll be wrenching on it tomorrow, I'll make a before & after vid. Thanks again

 

[Mike NXP]

Hmm shoot, so it never had this issue before right? It was all working just fine and then you did the alternator swap and now belt is popping? If yes the problem is new then it must be related to work just done...

- What did you remove to swap alternator, did you remove idler or tensioner pulley?
- Any chance the pulley is installed backwards on alternator ?
- Same question if you removed idler / tensioner pulley. Make sure cup washer is on the correct side and pulley not flipped

 

[2001LC]

Thanks Mike. Yes, correct belt. Tensioner seems to be leaning outward a bit (that's why I was asking about any adjustment that I may not know about) and that's also why I'm replacing the bearing first. Yes,100% sure the pop is being caused by the belt popping back on the alt pulley. I'll be wrenching on it tomorrow, I'll make a before & after vid. Thanks again

If tension bearing bad or not properly seated. Bad bearing can get so bad, pulley wobbles out of alignment. New bearing seated properly, may be all that's needed.

But a few things to look at:

1. Alternator pulley & mounting bolts, properly seated and torqued down.
2. Condition of tensioner. I've seen a few. Where the front assemble, where pulley seats/bolts to. Have become cock-eye. Such that. Even with a good pulley & bearing. Pulley rides at angle and belt wears into body of tensioner. These tensioners, should be replaced.

 

[UncleLDP]

As I suspected. I replaced the tension pulley and the popping noise is gone. The belt is now seated properly on the alternator pulley. Sorry, forgot to video.