Serpentine belt creep

[JIMMYRIG]

I replaced my serpentine belt a week ago as preventative maintenance. A few days later it blew off on the freeway. I did a roadside repair and havent had it fall off again, however its been jumping a tooth on the crank and power steering pulley. I keep re-adjusting but this is the second time its happened in the last few days. The only thing I ever unbolted/adjusted was the PS pump. Any ideas?

[eaglescout526]

With the belt off does all the pulleys line up?

[JIMMYRIG]

Visually nothing looks off but I don't know if that means anything

[eaglescout526]

Ehhhh. Which engine do you have?

 

Whats the condition of the balancer?

[JIMMYRIG]

4.0

Not sure the condition

Honestly its probly never been replaced

What would indicate needing replacement?

[89 MJ]

If the rubber in the balancer is cracked, it needs replacing. 

[eaglescout526]

[fiatslug87]

Are you sure you’re tightening the belt enough?

[JIMMYRIG]

13 minutes ago, fiatslug87 said:

Are you sure you’re tightening the belt enough?

It’s got a decent amount of tension.

[JIMMYRIG]

56 minutes ago, 89 MJ said:

If the rubber in the balancer is cracked, it needs replacing. 

 

[89 MJ]

Yup, that needs replacing because of the cracks. 

[JIMMYRIG]

26 minutes ago, 89 MJ said:

Yup, that needs replacing because of the cracks. 

Ok, just confused why it didn’t throw the old belt off

[fiatslug87]

Two of mine were in much worse shape and never had an issue with the belts.

 

[89 MJ]

I’m not saying for sure that is the issue, but it could’ve slipped and might be at least partially responsible. 

[JIMMYRIG]

Is there any way the yaw of the PS pulley could be off? Its the only thing that i unbolted when i swapped the belts

[JIMMYRIG]

Used a laser to see alignment of pulleys. Whoever did the PS last didn’t press the pulley on all the way so it was out of alignment

[fiatslug87]

Glad you got it figured out. 
 

Thanks for posting your findings, it will help people in the future.

[75sv1]

Its just not the cracks on the Harmonic balancer. Yours looks like the elastomer has cheeked out. So, it has lost its bond. Replace it ASAP. It can damage the main bearings. Direct experience on my part. A harmonic balancer is about $50-$60. Mine caused squealing of the belt.

[olddude]

47 minutes ago, 75sv1 said:

Its just not the cracks on the Harmonic balancer. Yours looks like the elastomer has cheeked out. So, it has lost its bond. Replace it ASAP. It can damage the main bearings. Direct experience on my part. A harmonic balancer is about $50-$60. Mine caused squealing of the belt.