jd101

Ever since I replaced all the three belts, water pump etc on my Civic 2003 four months ago, I have been hearing squeal noise for few seconds and then it goes away. I did not have this sound before. I don't know for sure where the sound is coming from, I believe it is from the AC belt but not so sure.

It seems I can reproduce this sound especially if I turn on AC when the engine hasn't heated up completely. After I turn on and off AC few times, then I can not produce this noise. After the engine is heated up then it is hard to reproduce this sound.

It seems when car has been sitting idle not running for few hours then first time you turn on AC, you can bring this sound for few times, then it wouldn't do it.

I'm at loss, if it was tensioner pulley it would do it all the time. If it was AC bearing etc , again it would do much more often when AC is running.

Mechanic tightened the belts twice and says there is no further room to go.

lazlong

If it only does it on startup then I wouldn't worry about it, it's just a cold belt. If it did it all the time or every time you have the A/C on then I would look at either tightening or loosening the accessory belt. And if that doesn't help then I would look at the compressor clutch and crompressor- in that order.

jd101

If it was compressor you would think it would be there all the time whenever the compressor is running, the same can be said about clutch but there could be something going on the moment clutch engages for the first time whenever you turn on the A/C. Just so you know the squeal may last for 5 secs and then it stops on its own even if the AC is running.

lazlong

I had this exact problem on my 2001 for 2 years before I sold it- with no problems so, I just ignored it for that 5 seconds.

There are some products you can use to quiet belts from belt dressing to an ordinary bar of soap. Just google "how to quiet a belt".

jd101

Thanks, people may not buy when you want to sell it if they hear squeaking sound thinking there is some problem.

In any case, I can't figure out what changes after car is heated up? or when weather is warm as opposed to frigid temps. This summer I will know if it stops squeaking. You had mentioned about cold belt. Does it mean belt is stiff when it is cold and doesn't have better grip or when engine is cold, first time you turn on A/C, it puts excessive load on serpentine belt and once it is loosen up then it doesn't squeak any more.

My mechanic is not using any gauge to know what the tension is, I believe he is going by his experience and feel. Is there a document that shows what the specs are for this belt?

I have read somewhere that they had loose compressor which was causing this brief noise.

lazlong

The belt itself is cold and stiff, just like the engine is. It takes the belt a second or two to warm up and loosen a little bit.



Sorry about the fuzzy pic, it was taken years ago on a crappy phone cam.

jd101

The squeak is not heard as soon as you crank the engine. If I turn AC/defrost after 2 mins of starting engine then I hear the squeak, whenever AC is turned ON for the first few times after the engine had not been running and is cold. Once the engine reaches temperature then usually you can not produce this sound.

lazlong

Compressor clutch may be going.

jd101

I would like your help on process of elimination.

It can't be alternator and related assembly such as alternator pulley, bearing etc, correct, since if it was alternator then I would hear this all the time , right when I start the engine.

That leaves with AC idler pulley, AC clutch pulley. Idler pulley is in effect all the time, since the noise is brought on when the AC is turned on, that points to AC clutch or the belt may be loose so when the belt is cold, the first few times AC clutch is engaged , you hear this squealing.

Mechanic thinks it could be dust on the AC clutch/pulley, if that was so, the noise would be there all the time whenever the AC is running. Correct?

lasm97

I had a squeal too and it was always heard when the AC was on. These past couple of days it was louder than usual and yesterday in the middle of a drive through after 15 mins of driving, the AC stopped working. Now I need to figure out what it is....ugh! It's too hot in FL!