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Weather related

about two month ago replace a bad alternator and belt. about two week ago only when weather temperature change belt squeal as long as it hot no problem. if it start raining belt squeal if I hit the gas change the(RPM) it stop squealing until I get to a stop sign. and it start squealing again but like I said as long as weather is hot no problem.

belt is probably too loose

It looks like English but I can’t understand what you are saying.

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Bad or poor quality belt, tensioner not working properly, pulleys out of alignment or worn, or bad alternator alignment, pulley, drag. I dunno what else to say except those are pretty much the options. I only use Delco alternators anymore due to the crap that’s on the market but I haven’t had to buy one in years.

Worn and/or glazed belt. It grips when dry, slips when wet. Time to replace it… check the tensioners and the pulleys, too.

If the belt is new and looks ok, and the belt tension is correct, I’d guess the alternator you installed has a failing bearing. The replacement alternator is probably a rebuilt unit, maybe something wrong w/the bearing they installed to rebuild it, or they didn’t bother to install a new bearing. Double check the belt and belt tension and belt alignment first. But if those all look ok, you’ll probably have to replace the alternator with a known good one as a test to see if it makes the noise go away. If it does, a least you know the cause and can decide what to do about it at that point.

Edit: You could temporarily loosen the belt so the alternator didn’t spin too as a temporary test, as long as there’s nothing on that belt routing that is critical, like the water pump.

Tensioner and belt are the most likely fix. The belt may be young in terms of miles, but if it’s been squealing it’s probably glazed.

Attempt to turn the alternator pulley counterclockwise using a socket on the pulley nut. If the alternator pulley slips on the belt as it turns the belt tensioner is weak. NOTE; do not rotate the pulley more than about 1/4 turn backwards if it is not slipping on the belt. If the belt doesn’t slip it will rotate the cranksaft and camshaft backwards and in a few turns may damage the timing gear/chain.