Ok, so when I bought my '91 Cherokee, the go who sold it to me said that he had owned one just like it previously and at about 200,000 miles it started making a whining noise. He told me it was the old harmonic dampener and said I should listen at mine when she gets at around 200k miles. Well, Im close, and I'm hearing a whine. It doesn't seem like a belt squel or anything, so Im aksing:

1) Would this be the probably cause?
2) How do I make sure?
3) Could the vibrations of the failing balancer cause a spark plug to pop out?

Thanks guys.

 

1. Who knows...thread lacks info...
2. look,feel and listen around.
3. Not a chance.....

 

I've seen multiple 4.0 powered XJ's with separating balancers. If you look down at the balancer you'll see a rubber ring that looks like its slipping out of the balancer. You'll know it when you see it, its unmistakable. If you see this, its time for a new one. Sure you can probably get thousands of miles out of it and lord knows I have but the part is still failing and its not good for your rotating assembly. Can it cause a spark plug to come out? I doubt it. Can it cause belt whine? Absolutely.

 

can it grenade through your radiator or oil pan? Most definitely.