question about belt squeal
01-08-13, 08:27 PM
#1
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question about belt squeal
so when I opened the hood to take a look I noticed the pulley on the ac compressor isnt turning. Should it be, because if it is that would likely be the source of the noise
01-08-13, 11:18 PM
#2
Is it a loud squealing noise? Can you smell burning rubber? The ac compressor could probably be locked up, but if it was, you could tell, power decrease, harder to accelerate,and it would almost die at idle. Since the motor has to work a lot harder to spin because of the locked up compressor.
01-09-13, 10:00 AM
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Is it a loud squealing noise? Can you smell burning rubber? The ac compressor could probably be locked up, but if it was, you could tell, power decrease, harder to accelerate,and it would almost die at idle. Since the motor has to work a lot harder to spin because of the locked up compressor.
And at times it does idle like its about to die
um...I noticed the actual pulley the belt goes around is staying stationary rather than spinning like the others
01-09-13, 10:37 AM
#6
that sounds like something has gone wrong, I wouldn't drive it a whole lot with a locked up pulley.
maybe take the accessory belt off and try and see if you can free it up.
If not you may need to replace, or see if you can repair the pulley/bearing or whatever is locked up.
maybe take the accessory belt off and try and see if you can free it up.
If not you may need to replace, or see if you can repair the pulley/bearing or whatever is locked up.
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01-09-13, 12:38 PM
#9
no idea, if it has holes in the pulley maybe get a piece of wood on one of them and give it a tap with a hammer/rubber mallet and see if it turns any. I wouldn't hit the gear directly or even too hard though.
sometimes on accessories that you can get the pulley off you can press out the old bearing and press in a new one. never messed with the A/C one before so yeah, not sure of the specific steps on that one.
If its something internal to the compressor thats not letting it turn, your chances of "freeing" it may be low.
sometimes on accessories that you can get the pulley off you can press out the old bearing and press in a new one. never messed with the A/C one before so yeah, not sure of the specific steps on that one.
If its something internal to the compressor thats not letting it turn, your chances of "freeing" it may be low.
I have no noise, well except for the PS pump noise...
01-09-13, 01:40 PM
#11
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That's what I'm wondering now... Is there a clutch that should engage when the ac is on and the pulley spins freely all the time, or is the pulley not spinning and the belt going around it normal
01-09-13, 01:56 PM
#12
There should be...
How the AC compressor clutch works
The squeaking you hear could be the tensioner belt pulley bearing...
Sound's norm to me
How the AC compressor clutch works
A belt drive attached to the engine spins constantly, providing energy for the AC compressor. The belt turns a rotor, which has a friction plate attached to it. Near the rotor is an electromagnet--a coil of wire which produces a magnetic field when current is run through it. Across from the friction plate is another friction plate attached to the rotor that powers the air conditioner.
When the electromagnet turns on, it produces a powerful magnetic field through the rotor. Since the fan belt rotor and the air conditioner rotor are both made out of iron, the magnetic field magnetizes both of them, pulling them towards each other. This causes the friction plates to push tightly in to each other. Initially, the rotor friction plate is turning and the compressor friction plate is not. Once they are touching, however, friction between the two plates makes the air conditioner rotor spin. When the electromagnet is turned off, the friction plates spring apart and the compressor stops moving.
When the electromagnet turns on, it produces a powerful magnetic field through the rotor. Since the fan belt rotor and the air conditioner rotor are both made out of iron, the magnetic field magnetizes both of them, pulling them towards each other. This causes the friction plates to push tightly in to each other. Initially, the rotor friction plate is turning and the compressor friction plate is not. Once they are touching, however, friction between the two plates makes the air conditioner rotor spin. When the electromagnet is turned off, the friction plates spring apart and the compressor stops moving.
Sound's norm to me
01-09-13, 02:00 PM
#13
you guys confused me for a sec how a belt can turn around a pulley that isn't.
I just went out to my car and looked at it, and all of my stuff is working.
Engine on, a/c off = only the outside groove part of the pulley spins with the belt (almost looks like nothing is spinning but I touched it from the front and the grooved part definately spins).
Engine on, a/c on = the outside part still spinning, but now the inside part is spinning same speed as the pulley, so the clutch is between the inside part and the outside grooved part.
There are no holes or anything in the middle to try and turn it so no go on that one. Are you positive the outside part isn't spinning because its basically the edge that is only spinning where the belt rides. get a good light on it to make sure. inside only spins when A/C is on.
and SC400slide has a point, I have had to replace the tensioner pulley bearing before on another sc3.
you can either replace whole tensioner or press out the old bearing, order the same size one and press it back in.
If the spring on your tensioner is no good, as in the marks on the tensioner do not line up with the belt on, just go ahead and replace it if you have already replaced the belt. if you have an old belt, replace that first and see if the marks are within range.
I just went out to my car and looked at it, and all of my stuff is working.
Engine on, a/c off = only the outside groove part of the pulley spins with the belt (almost looks like nothing is spinning but I touched it from the front and the grooved part definately spins).
Engine on, a/c on = the outside part still spinning, but now the inside part is spinning same speed as the pulley, so the clutch is between the inside part and the outside grooved part.
There are no holes or anything in the middle to try and turn it so no go on that one. Are you positive the outside part isn't spinning because its basically the edge that is only spinning where the belt rides. get a good light on it to make sure. inside only spins when A/C is on.
and SC400slide has a point, I have had to replace the tensioner pulley bearing before on another sc3.
you can either replace whole tensioner or press out the old bearing, order the same size one and press it back in.
If the spring on your tensioner is no good, as in the marks on the tensioner do not line up with the belt on, just go ahead and replace it if you have already replaced the belt. if you have an old belt, replace that first and see if the marks are within range.
Last edited by Ali SC3; 01-09-13 at 02:06 PM.