Alternator would have to be tightened if it is an older vehicle that allows you to do so.
Loosen the alternator and push the alternator down and pull the belt off, put new belt over crank and water pump pulleys and around alternator pulley and pull up on the alternator to where the belt is tight and tighten the alternator bolts down.
Loosen all the bolts on the alternator and push down on the alternator and the belt will be loose and you can take it off, to reinstall you put new belt around the water pump and crank pulleys and then put it over the alternator pulley and pull up on the alternator and tighten the bolts back up and you should have a 1/2 " play in the belt when you push down on it, if you have more than that you need to unloosen alternator bolts again and pry the alternator up with a large screwdriver and re-tighten the bolts again and recheck.
First you need to remove the AC belt to be able to install the alternator belt.This can be accomplished by loosening the hinge bolt and set bolt on the side. Then adjust the tensioner bolt till you can slip the AC belt off.Then you need to loosen the alternator hinge bolt and the set bolt on the side. Then adjust the tensioner bolt to the point where you can put the new alternator belt on to the main drive pulley, water pump and alternator pulleys. Then tighten the tensioner bolt till the belt has about 1/2 of give in the middle of the belt. Once in place tighten the set belt and hinge bolt.Repeat the same process for putting the AC belt back on.***I have replaced my alternator belt 4 times in the last two years and need to install it for the 5th time. I just found out that there is a consistent issue with Protoges and aftermarket alternator belts and proper fit. Save your self the time of doing this job over and over again and buy the OEM belt from your Mazda dealer.***
The alternator is mounted on an adjustment bracket. You can loosen the lower bolt a couple turns then loosen the upper bolt a couple turns and slide the alternator forward to get the old belt off and the new belt on. Hold the alternator back with a big screwdriver or breaker bar to re-tension the new belt while you tighten the top bolt, then tighten the bottom bolt.
This was hard to do on my 86 2.5L 4 cylinder because in order to put the new alternator belt on... you have to get the other belt off... first what you have to do is loosen up the 2 pivot bolts on the AC compressor from underneath the car.. mine were pretty stubborn but i eventually got em to budge... once you can move the AC, remove the crank/water pump/AC belt. then loosen up the alternator pivot bolt located on the underside of the alternator...(this can be done from either top or bottom) once you can move the alternator.. slip the belt onto the alternator pulley and around the water pump and crank. then tighten the alternator pivot bolts while putting as much possible tension onto the belt and re-tighten alternator into place. then put or replace crank/water pump/AC belt and re-tighten the AC while putting as much possible tension on the belt by pushing the AC forward with a pry bar or screwdriver. good luck
there are two bolts on the bottom af the alternator you have to loosen and one on top in an arch with a slot for adjustment loosen all three and pull the alt towards the front of the car to remove the belt. install the new one then snug the bolts and adjust the tension then tighten all bolts. even high quality belts will need tightened after they stretch,i usually have to re tighten twice then they are fine,dont overtighten belt tension or you may damage alt or water pump bearings
There are three bolts holding your alternator in. One's at the bottom. Don't worry about it. One's at the top and the head points toward the side of the car. Loosen it but DON'T take it out! The third is at the top, pointing toward the firewall. Put a 12mm wrench on the nut and turn it until you can put your thumb halfway between the water pump and the alternator, and push the belt down between 1/4" (6mm) and 1/2" (12mm). When you're there, tighten the bolt you loosened in the last step.
Without a year and engine size, there's no way to be definitive with an answer. If the car is newer, say post 1993 or so, it's likely to have a serpentine belt - one belt that drives the accessory devices like water pump, alternator & power steering. If it's older and has a dedicated belt, the basic idea is to loosen the alternator PIVOT bolt and pry the alternator outwards against the belt - tighten the pivot bolt to lock it in. See "Related Questions" below for more
This was hard to do on my 1986 2.5L 4-cylinder because in order to put the new alternator belt on... you have to get the AC belt off... to replace either belt you have to remove both. first what you have to do is loosen up the 2 pivot bolts on the AC compressor from underneath the car.. mine were pretty stubborn but i eventually got em to budge... once you can move the AC, remove the crank/water pump/AC belt. then loosen up the alternator pivot bolt located on the underside of the alternator...(this can be done from either top or bottom) once you can move the alternator.. slip the belt onto the alternator pulley and around the water pump and crank. then tighten the alternator pivot bolts while putting as much possible tension onto the belt and re-tighten alternator into place. then put or replace crank/water pump/AC belt and re-tighten the AC while putting as much possible tension on the belt by pushing the AC forward with a pry bar or screwdriver. then tension up the belts so they give no more than 1/2" when you pull them at the midpoints of their spans.
Just slightly different than on lesser cars: Saabs have two alternator belts that run in parallel. This belt pair also drives the water pump, so they wanted to be sure you wouldn't get stranded. But it's pretty easy: your alternator runs on an adjustment track. Loosen both bolts and pivot the alternator so you can get the belts off. Look how they're routed before you remove them. If you have AC the belt for that is blocking in your alternator belts, so loosen the compressor and take it off. Then put the new belts you bought in place, tension the alternator (I stick a broomstick between the alternator and engine, and pry the belts tight), tighten both bolts, tension the AC compressor and tighten it, and you're done.
A RENCH................GENIOUS!! The broken screw will have to be replaced. A loose alternator belt will not recharge the battery - might also cause the engine to overheat if it is the same belt that drives the radiator fan and water pump. If the screw is broken inside the alternator, you can reverse-drill it out with an EZOut or you can just drill it out and replace with a bolt and nut. Other solution would be to buy another alternator. I don't know of any way you can tighten it temporarily except for maybe using a wooden wedge between the alternator and the alternator bracket or by using a piece of wire to hold it as far back as you can on the bracket. But these are emergency and temporary techniques - not a solution.
I wanted to know why the truck did not overheat. Running on I95 for 65 miles at approx 60 mph. As long as the water pump is being powered by another belt it will not overheat. The alternator belt drives the alternator which keeps the battery charged and nothing else. Eventually the battery will loose all it's charge and the engine will stop running but a broken alternator belt will not cause it to overheat unless that same belt is driving the water pump. What if the belt is driving the water pump. If the belt that broke is driving the water pump the engine will overheat eventualy. Do you know what the shut down temperature is?