Squeaky alternator...sometimes

[Jason72Bronco]

So, almost every time when I start the Bronco up, their is a loud squeaking coming from near alternator. It usually will only last about 5 seconds, and then goes away and never comes back while driving. Squeaks again next time I start it....then goes away after about 5 seconds. Rinse, repeat.

Do you guys think this is the pulley or belt tension. (The belt is brand new)
Thanks,
Jason

 

[ScanmanSteven]

Belt is slipping because you just used power from the battery to start the Bronco so regulator is calling for a full charge so it slips as it starts and is loaded. Since it stops after a few seconds I wouldn't worry about it. You could tighten the belt a little but there is a point of too tight.

 

[Viperwolf1]

Usually this happens with high power alternators driven off a single v-belt. Solution is to get better traction at the alternator by using a larger diameter pulley or even using a dual belt pulley. A better option is to switch to serpentine drive accessories.

 

[blubuckaroo]

I agree with the above posts about the higher than normal load on the alternator/belt caused by using the starter.
You can experience bad belt traction, even with a new belt. Sometimes the pulley is worn out, or glazed. Sometimes the new belt just doesn't fit the pulley properly. If the belt rides all on way to the bottom of the pulley's groove, it can't wedge and grip properly. Over tightening it won't help here. It could be either a bad alternator pulley, crank pulley or both.