'90 XJ Harmonic Balancer question

1990 XJ 4.0 AW4... I have been chasing a squeak for the last month. I thought it was fixed when I replaced the water pump 3 weeks ago. Saturday the squeak came back and after listening for a while, I replaced the idler pulley, but afterwards I was sure it was coming from the water pump. So, off to NAPA for another pump. The problem was back after about a half hour of driving. The alternator is 6 months old and the problem is definately not there.

When I look at the belt from underneath, I see there is only about 1/8 inch between the rear edge of the belt and the timing cover. I looked at my neighbor's 1988 XJ and it has about 3/8 inch clearence. The front of my balancer is even, meaning the front edge of the inner steel hub is flush with the front edge of the outer steel ring, as was my neighbor's. It also looks like the belt is riding at the rear of the fan clutch pulley, which is the next part downstream from the harmonic balancer.

What is this thing the fan clutch is bolted to, is it just another idler assembly with an internal bearing? Do they fail and make a noise like this?

If you have a 1990 XJ, can you tell me how much distance you have from the rear of your belt to the timing cover? Is there a spacer behind the harmonic balancer the previous owner could have lost?

TIA

I replaced my balancer pulley on my 88 4.0 approx two months ago (MOPAR oem part) and it appears to have approx 1/8" between it and the cover when viewed from below, looking up. The rearmost part of the pulley is thin metal, maybe 1/16", and looking down at the timing pointer, it is 'just barely' hidden by that pointer.

Check power steering pulley and that there is enough fluid... I had a skueeking noise around 1250 rpm. It went away when I filled fluid container...

replaced my 87 XJ's 4.0L harmonic bal years ago, when under load it can wobble and make contact with the timing chain cover. Check the cover for signs of contact. I caught mind just before it wore a groove all the way through the cover.