when i bought my jeep it had a squeal and i finally figured out it was the belt so i put a new one on and it doesn't squeal unless it gets wet, like when i go thru a big puddle or wash the engine. what could make this happen and is it bad?

 

Have you tighten the belt? 4.0L belt has to really tight compared to other vehicles.

 

Minor pet peeve of mine- everybody suggests tightening the belt but nobody seems to include a picture of how to do it so here you go:



That is from a 1999 XJ. The bolt in the center with the writing on it is the tensioner adjustment bolt. If you tighten it (clockwise) you'll tighten the tensioner. That one used a 15mm socket. Took about 30 seconds to clear up the squealing in the girl's Jeep.

 

Yes, the serpentine belt on the 4.0 needs to be awfully darn tight to stay quiet. The KRIKIT-II tension gauge can be helpful here if you aren't confident in doing this by the seat of your pants.

Also, some belts are more susceptible to noise than others. I generally recommend the Goodyear Gatorback. Excellent belt with low stretch (meaning you usually don't have to tighten it up after an hour of running!)

NEVER use belt dressing on a serpentine belt. That stuff was designed for the old v-belts. It can temporarily help with squealing, but after it gunks up your belt, you'll be even worse off than you started!

 

so do i have to undo all the bolts like i was taking it off to tighten it or can i just turn the tensioner?

 

newer jeeps you just turn the tensioner, older jeeps is alittle more involved.

 

Just turn the tensioner. I think it s 14mm or 15mm bolt could be wrong.

I think it helps to disconnect the temperature sensor from the t-stat housing. You will be able to get a socket in there a bit easier. the sensor has a small flap on the top that pushes down. Super easy to disconnect and reconnect.