Automotive

AC makes funny whirring noise- bearing gone?

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  • Aug 14th, 2021 10:56 am
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[OP]
Banned
Jun 21, 2021
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AC makes funny whirring noise- bearing gone?

hi everoyne.
my AC is having some issues it seems.
So when it first starts up, it's making some whirring noise.
At initial start up, sometimes the AC works no problem. But then if I pull up to a stop sign, the AC basically stops blowing cold air.

Once the car starts moving, cold air starts again no issue.
If the car is hot - been running for a while, like 3-5 minutes, no issues with it at all. The occasion "whirrring sound".. and not the AC condenser fan whirrr.. sounds a bit more like a bearing..

so from this dianosis, Im thinking that the belt that drives the compressor is running into resistance.. E.g. the bearing for the compressor is giving resistance to the belt so it's not turning freely.. except after it spins for a while i guess it losens up and starts to turn no issue.

1) is this possible to lubricate? do you think it would help?
2) or would this be a more serious problem and require replacement?

this is for a 2013 vw jeta
18 replies
Deal Addict
Sep 22, 2009
3234 posts
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Markham
peterschiff wrote: 1) is this possible to lubricate? do you think it would help?
2) or would this be a more serious problem and require replacement?
You can't lubricate the belt. However, you can check the belt condition and its tension.
[OP]
Banned
Jun 21, 2021
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BDSL wrote: You can't lubricate the belt. However, you can check the belt condition and its tension.
yes not the belt. would it be possible to lubricate the shaft that is driven by the belt?
would that even matter, or is it more a matter of it seizing inside the actual compressor.
Deal Addict
Sep 22, 2009
3234 posts
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Markham
peterschiff wrote: yes not the belt. would it be possible to lubricate the shaft that is driven by the belt?
would that even matter, or is it more a matter of it seizing inside the actual compressor.
Tere are many idlers and pulleys. You don't lubricate those.
First thing first, check belt condition and tension.
Last edited by BDSL on Aug 11th, 2021 6:59 pm, edited 1 time in total.
Banned
Jun 4, 2020
1634 posts
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Clarington, ON
The compressor isn't spinning as fast when you are stopped. My vehicles aren't as cold sitting at a light either. There are rated speeds for compressor where they are effective.


Re change in sound when turning ac on. Could be additional load in the belt is causing a worn pulley or bearing somewhere. You're also clutching in a compressor. It may just be normal.


Finally, because this is RFD... If it's that concerning, buy a tesla!
Deal Addict
Sep 22, 2009
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Markham
KevinM56081 wrote: Finally, because this is RFD... If it's that concerning, buy a tesla!
Haha...
Banned
Jun 4, 2020
1634 posts
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Clarington, ON
Further thought..... Vehicles with electric fans (all ice stuff produced this century) have electric fans. Are you hearing the fan engage?
Member
Feb 28, 2021
246 posts
216 upvotes
A/C refrigerant works best when you’re vehicle is moving because air is being moved through the condenser which cools it down as it heats up significantly from being compressed by the compressor
Deal Guru
Feb 9, 2006
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Brampton
TBH your description doesn't make it sound like any kind of bearing issue it sounds like the AC compressor's electromagnetic clutch.

It needs to be inspected and tested in some cases the clutch can be removed from the compressor and replaced in other cases the whole compressor needs to be replaced.
[OP]
Banned
Jun 21, 2021
59 posts
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tebore wrote: TBH your description doesn't make it sound like any kind of bearing issue it sounds like the AC compressor's electromagnetic clutch.

It needs to be inspected and tested in some cases the clutch can be removed from the compressor and replaced in other cases the whole compressor needs to be replaced.
if there were issues with clutch though, it wouldn't turn on at all?

In any case, whats the cost to replace an AC compressor on a car + labour?
I'm thinking 2 hours labour + parts, $1,000 at the stealership?
Deal Expert
Mar 23, 2004
33251 posts
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If it's a motorboat type noise, you are likely just low on refrigerant. Not low enough to inhibit compressor operation but low enough that at low speed/idle/just turning on the AC, you'll get that noise.

As a note lot of more recent model cars don't have any AC clutch at all, the pulley is engaged with the compressor at all times but due to the variable nature of the design the compressor places insignificant load on the engine when the AC is off--the pulley is basically just freewheeling at that point. Edit: It's a 2013 Jetta--yeah pretty sure this is a clutchless A/C compressor (100% sure if it's a 2.0T or 1.8T). So no clutch to make any noise.
Member
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Jun 11, 2019
322 posts
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North York, Toronto
Pro-tip, when you use your AC turn in the recirculation button too. It's been very hot lately and that allows cool air to circulate, instead of converting +30c air into cold air. It also extends the life of the condenser.
[OP]
Banned
Jun 21, 2021
59 posts
36 upvotes
ES_Revenge wrote: If it's a motorboat type noise, you are likely just low on refrigerant. Not low enough to inhibit compressor operation but low enough that at low speed/idle/just turning on the AC, you'll get that noise.

As a note lot of more recent model cars don't have any AC clutch at all, the pulley is engaged with the compressor at all times but due to the variable nature of the design the compressor places insignificant load on the engine when the AC is off--the pulley is basically just freewheeling at that point. Edit: It's a 2013 Jetta--yeah pretty sure this is a clutchless A/C compressor (100% sure if it's a 2.0T or 1.8T). So no clutch to make any noise.
is it common to lose refrigerant? maybe I got a leak somewhere
Deal Expert
Mar 23, 2004
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peterschiff wrote: is it common to lose refrigerant? maybe I got a leak somewhere
Some refrigerant will escape through fittings and schraders over time, you don't really need a leak per se. You might have a leak but typically a true leak would be something fast enough that your AC would probably stop working altogether in short order (compressor will not turn "on" if charge is too low).

So no you should never need to "top up" refrigerant like it's oil or washer fluid; but after 10+ years you may be getting into a lowered charge situation, depending on conditions, environment, etc. Your car could already by as many as 9 years old so it's getting up there. You may have a leak but you just as well might not.

In any event if you take it to a reputable shop they will typically check for leaks if the charge is low, or you can request them to. Unfortunately A/C is not that much of a DIY repair because of the equipment needed. In the US you can buy R134a in stores, get yourself some manifold gauges off Amazon, and try your hand at it. However in Canada you can't buy the stuff; and, with the land border closed, can't just take a drive over to get some either. Plus it's not really a good idea to just pump in refrigerant when you don't have the proper equipment or knowhow. You could end up damaging things worse and costing yourself a whole lot more money.
[OP]
Banned
Jun 21, 2021
59 posts
36 upvotes
ES_Revenge wrote: Some refrigerant will escape through fittings and schraders over time, you don't really need a leak per se. You might have a leak but typically a true leak would be something fast enough that your AC would probably stop working altogether in short order (compressor will not turn "on" if charge is too low).

So no you should never need to "top up" refrigerant like it's oil or washer fluid; but after 10+ years you may be getting into a lowered charge situation, depending on conditions, environment, etc. Your car could already by as many as 9 years old so it's getting up there. You may have a leak but you just as well might not.

In any event if you take it to a reputable shop they will typically check for leaks if the charge is low, or you can request them to. Unfortunately A/C is not that much of a DIY repair because of the equipment needed. In the US you can buy R134a in stores, get yourself some manifold gauges off Amazon, and try your hand at it. However in Canada you can't buy the stuff; and, with the land border closed, can't just take a drive over to get some either. Plus it's not really a good idea to just pump in refrigerant when you don't have the proper equipment or knowhow. You could end up damaging things worse and costing yourself a whole lot more money.
i was looking into doing it myself, but you're right.
it seems like Princess Auto, Canadian tire, all sell R12a, which is a R-134a replacement.... don't think it's a good idea to use that... if i just pump in R12a i will have a mixture of the two gases likely wont be as good.
i defitenily don't have the tools to 'vacuum it out'.. I mean I guess it's a pressure system so you can't discharge all of the old stuff, then use the r12a+oil mix kit from Canadian tire...
just not sure thats something i would do with this car..
Deal Addict
Sep 22, 2009
3234 posts
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Markham
Have you check the belt and the belt tension? That doesn't cost money.
Check if any pulleys and idlers make noise...that doesn't cost money.
Then if they are all good, then buy a gauge and check the AC refrigerant pressure (i.e. low pressure port).
[OP]
Banned
Jun 21, 2021
59 posts
36 upvotes
BDSL wrote: Have you check the belt and the belt tension? That doesn't cost money.
Check if any pulleys and idlers make noise...that doesn't cost money.
Then if they are all good, then buy a gauge and check the AC refrigerant pressure (i.e. low pressure port).
they were all good man.

yeah gauge might be a good idea..
Deal Expert
Mar 23, 2004
33251 posts
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peterschiff wrote: i was looking into doing it myself, but you're right.
it seems like Princess Auto, Canadian tire, all sell R12a, which is a R-134a replacement.... don't think it's a good idea to use that... if i just pump in R12a i will have a mixture of the two gases likely wont be as good.
i defitenily don't have the tools to 'vacuum it out'.. I mean I guess it's a pressure system so you can't discharge all of the old stuff, then use the r12a+oil mix kit from Canadian tire...
just not sure thats something i would do with this car..
It's not really a "replacement" per se, it's a different product, alleged to be compatible. But you're right I wouldn't use it either. If you take to a shop they will leak test, evacuate, repair any leaks if necessary, and recharge with R134a.

The thing is in Canada you can't buy R134a as a consumer...for whatever reason, but you can buy "R12a" . In the US, the opposite is true--you can buy R134a but that R12a imposter stuff is unheard of lol. R12a is banned there because it's basically propane and isobutane--highly flammable. I wouldn't put that in your car, as mentioned.

BTW the AC compressors in these cars, the valve/solenoid is a common failure point. However usually when they fail you get no cooling at all, so I don't think that's your problem.
[OP]
Banned
Jun 21, 2021
59 posts
36 upvotes
ES_Revenge wrote: It's not really a "replacement" per se, it's a different product, alleged to be compatible. But you're right I wouldn't use it either. If you take to a shop they will leak test, evacuate, repair any leaks if necessary, and recharge with R134a.

The thing is in Canada you can't buy R134a as a consumer...for whatever reason, but you can buy "R12a" . In the US, the opposite is true--you can buy R134a but that R12a imposter stuff is unheard of lol. R12a is banned there because it's basically propane and isobutane--highly flammable. I wouldn't put that in your car, as mentioned.

BTW the AC compressors in these cars, the valve/solenoid is a common failure point. However usually when they fail you get no cooling at all, so I don't think that's your problem.
yeah, i agree. It's kind of a binary outcome when it's a more serious failure point.

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