'98 C5 "Warble" noise in AC??

[Roy M. Dudley]

Good Morning,
Roy Dudley here. Hoping for some insight on a weird problem in my C5. Here's the scoop: When I have the AC engaged, I hear a "warbling sound" that is quite pronounced. When I press the "AC OFF" button it goes away. It sounds like a bad water pump but only is effected by the AC button. QUESTION: Could this be a function of refrigerant level? The AC works fine, but the noise is driving me nuts! Could I hope for something as simple as a bad pulley or belt? Thanks everyone! Hoping for some "adult supervision" on this one!

Roy Dudley
San Francisco

[muddywaters]

Hi Roy, Sounds like the A/C clutch on the compressor by your discription, someone with a PhD in Corvette's will chime in I'm sure...............It's great...........

[Roy M. Dudley]

Hi Muddy,

Roy here. Thanks for the reply. The more I think about it, it's pretty much a "cause and effect" kind of experience. Push the button in...bird songs under the hood...Press the button "off"...no more bird songs. A/C clutch is probably it. Next QUESTION: Assuming I'm mechanically inclined, is this a home job?
Also, where would a civilian find a set of C5 shop manuals and what would you expect to pay for them? You guys have been great...thanks so much for the help!

Roy Dudley
San Francisco

[Roy M. Dudley]

Good Morning,

Roy Dudley again. I'm hoping to hear from someone who routinely works on their own Corvette -- Do the Shop Manuals available online do the job? And, have you ever swapped out an A/C clutch? Level of difficulty and can all work be done without having to get under the car?

Thanks everyone...you've all be great!

Roy Dudley
San Francisco C5

Originally Posted by Roy M. Dudley

Hi Muddy,

Roy here. Thanks for the reply. The more I think about it, it's pretty much a "cause and effect" kind of experience. Push the button in...bird songs under the hood...Press the button "off"...no more bird songs. A/C clutch is probably it. Next QUESTION: Assuming I'm mechanically inclined, is this a home job?
Also, where would a civilian find a set of C5 shop manuals and what would you expect to pay for them? You guys have been great...thanks so much for the help!

Roy Dudley
San Francisco

[DRTH VTR]

Originally Posted by Roy M. Dudley

Good Morning,

Roy Dudley again. I'm hoping to hear from someone who routinely works on their own Corvette -- Do the Shop Manuals available online do the job? And, have you ever swapped out an A/C clutch? Level of difficulty and can all work be done without having to get under the car?

Thanks everyone...you've all be great!

Roy Dudley
San Francisco C5

Roy-
Send a PM to GMJunkie or c4c5specialist. They could advise on what is necessary.

[Roy M. Dudley]

I'm new to the Forum...can you tell me how to address a question directly to GMJunkie or c4c5specialist? I just know how to reply to the thread.

Thanks for the adult supervision, Darth!

[DRTH VTR]

If you click on the user name for any of us, some options will open. One of them is to send a personal message to that member. I am not all that adept at computers. I hope this will also work:

gmjunkie:
http://www.corvetteactioncenter.com/...=newpm&u=16245

c4c5specialist:
http://www.corvetteactioncenter.com/...do=newpm&u=915

[TODD L GRIFFITH]

My 99' C5 Coupe did the same thing. It was the fan motor bearing.

[Roy M. Dudley]

Hi Todd,

Roy here. That makes perfect sense -- I think you might have saved me! Can you tell me where that component is located? Seems like the fan motor is probably somewhere under the dash behind the radio console someplace?

Can you tell me whether it was a dealer fix ($?) or something I could do at home?

Your reply is much appreciated,

Roy Dudley

Originally Posted by TODD L GRIFFITH

My 99' C5 Coupe did the same thing. It was the fan motor bearing.

[DRTH VTR]

Roy-
Parts can be expensive. I think the first thing to do is to be certain which part is making the noise. Paying an expert for diagnosis might well cost less than replacing good parts trying to hunt down the problem.
Jim

[TODD L GRIFFITH]

The location of the fan is above the passenger footwell. It is sort of a pain to get at, but can be done. This will enable you to isolate the noise and verify for sure where it is coming from. The bearings will make two different noises, one is a screeching noise and the other is more of a low vibration as the fan oscillates. I have no idea what a dealer might charge, but I bought a fan through GM, not too cheap either at just over $100.00.
I hope this is what the problem is to put your mind at ease regarding needing a new compressor, and start making a plan to get it fixed. It's getting hot out there.
Good luck my friend,
Todd

[Roy M. Dudley]

Good advice. I'll head over to the dealership and see what's cooking. I have to tell you this is the first time I've really engaged the forum and it's been great. Almost makes we hope something else goes wrong so I can talk to you guys again.

More later,

Roy