serpentine belt alternator temp pulley????

Ok sounds strange to me, but someone might have had this happen already. Sunday the 16th I changed the serpentine belt on the jeep. Back out the bolt then the tension bolt swapped the belt tightened the tension bolt and then the pulley bolt. Cranked it up no problems no squealing nothing. Ran it all week with no problems no sound nothing. Took a trip over to the western slope over the weekend. I’m coming home I-70 and stop to drop off two friends at the Morison park and ride. Still no problems up to that point. I’m backing out of the parking spot put it in drive to leave and it sounds like the belt squealing. I stop pop the hood inspect the belt it looks fine. Start it back up rev it a few times watch the gauges and it squealed a few more times then stopped. I drove home all the way back up to Greeley with no problems. Monday morning get up warm up the jeep for 5 min get all my stuff for work. Heading to work about 1 mile from my house it just starts off and on with the squealing. Stop turn it off check the belt felt like it still had good tension on it. It stops so I start going again. Check gauge light pops on. And alt/battery power goes dead pull over lights everything else is still fine. Squealing kicks up so I let it sit for a few and it’s fine start to head home (no tools to mess with the pulley) then the power comes back on as I’m driving and then the temp spikes on the gauge. I pull over let it cool off, but it cooled really fast even with how cool it was Monday morning I couldn’t see it cooling off that fast. I start to pull out again and no temp problems no power problems pull into the driveway and power gauge tanks on me again. I get it in the garage for the day and ride into work with the GF. Well last night I try to let some tension off and then add some back and forth and it seems to keep doing the squealing. At a loss hear hoping it’s not the alternator. Why would it spike the temp like that and the loss of power too loose I was thinking maybe??? OR?????

HELP!

Is there speck for how tight the belt should be between any of the two pulleys?

Add tension until it stops making noise, but not enough so it makes a different noise. The proper spec is between those two

I turn on the AC to full, and tension so when I turn on the AC, the belt does not cause the belt to slip.

I developed a squeal, my alternator crapped out shortly afterwards. may be related or may not but worth a look. My problem turned out to be a pinhole leak in the radiator in a spot hard to see, under the shroud in the upper right hand corner (as your sitting in the drivers seat). The coolant made the belt squeal and shorted out my alternator.
Te fine spray wasn't very obvious, the sticky feeling on my finger tips finally took me to the source.
If I have to adjust my belt without a belt tension tester, I usually find the longest run between pulleys and tighten until I get about 3/4" of give while pushing hard with my thumb.
Over tightening can be hard on the water pump bearings and others.
New belts will generally loosen up and have to be re tensioned.
I have a Cricket belt tension tester or maybe it's spelled Kricket forget which, cost was under $!0 when I bought mine way back when.

http://www.napaonline.com/MasterPag...PartNumber=KR2&Description=Belt+Tension+Gauge This is for a V belt, I imagine they also have one for a flat belt or maybe it's universal.

So I called the parts store and checked to make sure I had the right belt. Part # checked out to be right. I took the belt back off and compared it to the old one I kept for a trail spare and it’s just a bit longer. Ya I thought it might be a bit shorter like an 1/8th or so maybe a bit more. Call the part store to talk to the guy and he said bring the old one and new one in and we could compare the them with another new one. That was right before he told me they were closing in 10 min. So I put the belt back on and just hit it with a the tension bolt. I did the AC thing then would hit the gas from the motor bay and if it squealed I tighten it by 3 turns had to do that a bunch of times, but it’s fine now. Drove it around the neighborhood close to the house in case something happened I wasn’t too far from the house. All is fine now power is good temp is fine. Checked fluids all good there. I drove it into work today with no problems. I’m hoping this took care of it, and it doesn’t start in again a week later like last time. The nice thing is I have a 98xj too so I was able to see how tight that belt was compared to my 01.

Go get the gauge and tighten the belt properly. Most people under tension the belt. Its the Krikit II, or KR2 at the Napa link above. More info on the tool and its use. http://www.newenglandbelting.com/bt_method3.asp

Or if you have lots of money for a really expensive, accurate tool.
http://www.newenglandbelting.com/bt_method1.asp

Or like to do math.
http://www.newenglandbelting.com/bt_method2.asp