I just had a new alternator put in by my ace mechanic and
he also checked the belt and said it was ok & no real need to replace. It is old maybe more than 5 years or so but looks in good shape..... but

Many mornings (but not always) I hear it squealing (not too loud or bad) but enuf to bother me... I did try a little of belt dressspray but not really helps. It will squeal for about 10 minutes max until car gets little warmed up in Park & then go into Drive for a mile or maybe. Oh yehh.. I am parked o/nite outside always and car is subject to all the bad weather (very cold & wet mostly) here in Boston now.

This used to happen with old alternator and now still does it with newly replaced alternator... not really notice any battery voltage problems or guage dropping while it squeaking.

Should I get a new belt ?
Does the atmosphere/weather/humidity/air moisture all have some "big" effect on S. belts in terms of them stretching or shrinking and causing the squealing & noise. How does that affect the belt?

I guess a new belt would quickly eliminate the noise being brand new... BUT kinda low on $$$ and don't want to waste an otherwise decent belt doing a decent job for me.

Thanks

 

Check your tensioner. If it is past the arrow, the belt is stretched and needs replacing. If the tensioner isn't fairly stiff (don't know the torque spec off the top of my head), it may need replacing.

 

Thanks - I've noticed the markings on the tensioner and never knew they meant anything. But I believe the arrow is pointing within the little range of lines. But will take a careful look at it.

Again... does weather and moisture etc have a lot to do with the belt being noisy ??

 

Most of the time it's related to belt age, belt tension, and/or pulley wear.

Look at the grooves in the belt. Are they shiny? If so, the belt is riding down at the bottom of the grooves and not gripping properly. That can be either a belt problem (need a new one), or a worn pulley problem.

 

my belt does the same thing when cold
partly due to a different pully from some mid 50's chevy on my mazda alt.
the pully isn't that deep so hard to adjust to where it doesn't ride on the bottom but yet also gives enough tension that it grips.

I assume age has a bit to do with it as well beign the belt surface is fairly smooth, the pully being smooth I'm sure isn't helping either on the bottom.and like any rubber with age it gets hard harder rubber doesn't grip as well. cold rubber doesn't grip as well either being it gets even harder yet.
prolly just need to replace the belt and check your tension.