Alternator Belt Idler Pully

[DeepPower]

Well, I'm driving along after I got basically a new A/C system when suddenly there is no A/C at all. I get home ten minutes later, pop the hood, and lo and behold, the A/C compressor and alternator belt (Goodyear Gatorback belt) has broken! Right away I hook up the charger to the battery.

Like any good SHO owner I have spare parts which includes another belt. Never replaced one before, it's always been a "why don't you replace the belt, too" while the car was at my mechanic for other work.

So I see the Allen nut for adjusting the idler pulley for the alternator belt. As I turn the nut to the left, the nut screws into the housing, as I turn it to the right, the bolt gets higher - the reverse of what you would expect.

Meanwhile the idler pulley doesn't seem to be moving at all. Am I missing something here? How do I loosen the idler pulley so I can install my new alternator belt?

 

[Irish Pride]

You have to loosen the nut on the pulley first. The nut holds the pulley in place after you adjust the tension with the Allen screw.

 

[DeepPower]

You have to loosen the nut on the pulley first. The nut holds the pulley in place after you adjust the tension with the Allen screw.

So after I loosen the nut on the pulley, I can adjust the position of the pulley up and down by turning the Allen key? I'm not sure what you mean by "adjust the tension".

 

[luigisho]

The allen screw moves the pulley up and down with the belt on it which loosens or tightens the tension on the belt. Tighten the pulley nut to lock it in place at the desired belt tightness position. Any clearer??

 

[Irish Pride]

Yeah, loosen the nut and you will see what I mean. You'll need to lower the pulley to get the new belt on and then you'll need to tighten it.