I realise that there are multiple threads that could be resurrected for this but I was wondering if anyone had experience of the AC related noise that seems to be cured by a re-gas?

We have a 2011 FL2 and there is a noise that is only present when the AC is on, stops instantly when you turn it off. Not really there at idle and gets progressively louder on acceleration up to a point where it seems to get quieter, but then gets louder again when you pull off the accelerator peddle. AC works and gets cold.

I had hoped it was related to the alternator pulley which I recently replaced (along with the belt and tensioner/freewheel baring etc) but the noise is still there.

I did go to Halfords to take advantage of their free check which I assumed would result in having to pay for a top-up but unfortunately, I think, the pressure was in the green so it didn't need any gas.

We have a local independent which does some work for us but unfortunately their guy who does the AC stuff is off for a couple of weeks, I assume they could drain the system and put in gas with oil which, from what I have been reading, might be the culprit if low.

I don't think it's likely to be the AC clutch as it does engage and get cold, gave it a bit of a spin and a shake when I was doing the alternator and it seemed OK. The noise doesn't sound like a scraping sound which I guess is what that clutch slipping would be. Hard to describe but it's more like what i think it would sound like if you put an electric shaver in an empty tin, metallic drone/vibration rather than a scraping or screeching.

I guess I'm just after a sanity check that the symptoms match up to the AC re-gassing being a good point to try next. Only other thing I thought from reading the various threads was potentially the cooling fan bearings which had been suggested a few times, not sure on the behaviour of the noise from those with regard to idle/acceleration etc.

I have a very similar problem.

I went and had a regas and the noise subsequently got much louder !

I then replaced the FEAD belt pulleys - no better.

Whilst the belt was off a tried spinning both the alternator pulley and AC compressor. Neither felt rough.
But I dont know want they should feel like normally. So I could be missing something I suppose.

The only thing I could feel was a slight harshness when I spun the compressor itself rather than the compressor pulley (obviously its disengaged from the compressor). I tried using a sounding rod whilst the engine was running but couldnt detect the source of the noise.

Without a selection of different length V-belts I couldnt think of a way of running the alternator and compressor separately to eliminate one of the other.

So its booked in at my local independent garage for next Monday. Jules

This is link to Jules Thread ---- worth following as he is taking the problem solving step by step.
https://www.freel2.com/forum/topic40204.html FL2 XS SD4 Auto 2010 2012-2017 (21k - 91k miles) (MY2011)
FL2 Metropolis SD4 Auto 2014 2017- (16k - 79k+ miles) (MY2015)
Metro in its 11th Year of (Extended) LR Warranty / Full LR Service History
(Expensive, but Trouble/Worry free - hopefully?)

Thanks both. Hadn't seen that thread so interesting link.

Behaviour of the noise certainly seems very similar to that described in the other post. For me at least the noise is almost certainly not the alternator since I have swapped out the whole alternator and put a new pulley on the second hand replacement one I purchased before installing it and the noise is still the same.

Jules - not what I wanted to hear that gassing up potentially made it worse, I'm sure the same for you. Do you know if they put oil in at the same time as re-gassing yours? Holding out a sliver of hope that there has been some mention of oil being added curing a noise.

https://www.freel2.com/forum/post301232.html#301232

Only other thing I can think of are the cooling fans which I believe turn on with the AC but they should also work while the engine is running without the AC I would have thought?

I tried to record the sound by throwing my mobile on the dash and turning the AC off an on wile driving.



not sure how clear it is. Realistically if it does turn out to be the actual compressor I'm probably just going to live without AC.

Mine sounds similar to that you recorded.
I dont know if oil was added with the re-gas. But I'll see the bloke on monday and can ask.

There is no way I can put up with the noise - its louder than the engine when cruising.

AFAIK there is only one blower fan and turning the fan speed up or down made no difference. Jules

It is a very annoying sound so I just leave the AC off.

It'll be interesting to see what they say with regard to the oil. As I said the 'AC guy' is on holiday at the the garage we like to use but will reach out to them to ask if they can drain and re-gas/re-lube the system or if we need to find someone else that does it round here. I think that's my next port of call at least.

I was thinking of the radiator cooling fan but the behaviour of the noise is so tied to what I do with the accelerator that I doubt that's a reasonable thought, plus it should be going to cool the engine coolant even if the AC is off I would think.

Hi,
Changed the a/c clutch on mine fairly recently. Bought the clutch off ebay, came from Germany, about £65 if I recall. On gaining access to end of compressor by removing wheel and the plastic cover all easy to get at. I just replaced the clutch ( not the actuator ring as that seemed to be working OK). Only problem was removing/breaking circlip - wrong size pliers and replacement was included When apart problem was the bearing. Putting back together took a guess at gapping. Luckily correct first time but if a problem spacers/washers also from ebay about £5 also used on Ford/Volvo.
If you look on youtube plenty on how to change ac clutch on various cars and all the same method. Fairly easy job with basic tools.
Amazing how quiet it became afterwards.
Sorry away from home at present or more details.
Good luck

@oldsalt
What made you think it was the AC compressor clutch, and not something else?
Was your AC still working? Jules

Morning
A/C seemed to be working fine but had a slight "rattle" from RHS of engine when idling, disappeared if throttle blipped and couldn't be heard during most normal driving. It was'nt particularly loud but became annoying over time. After checking for anything loose that could be causing the noise I narrowed it down to the auxiliary belt area, and noticed what looked like belt "slipping" or not moving at a constant speed. Once again initially suspected tensioner and on removing the plastic shields to get a closer look noticed orangy/brown dust around clutch. On releasing the tension on the belt and then able to feel movement in the clutch.

I should emphasise that the noise was only on idling and the above took place over a few weeks and was more annoying than anything.

Hope that may be of some help

(mileage 99000 and nothing else done to a/c, belt changed when timing belt changed 2021)

I had the same with mine, drove me nuts, The Aircon worked perfectly, as some as I switched the Aircon on the noise appeared, priced a recon pump from a e-bay shop, £135 + £30 exchange fee. It arrived 2 days later and looked brand new,
I had to swap pulley + clutch over. PIA to get old out and new in. The drive belt+ tensioner+pulley are less than 2 weeks old as I assumed they were part off the noise issue so no need to fit new.
Got it regassed £67 now icy cold and no noise.
Money,time and lots of scratched arms but we'll work it.

Mike - did you try re-gassing before swapping out the pump?

£130 sounds doable and I suppose I could do the work myself other than what to do with the gas in the system, do you remember the name of the seller?

No, I searched on a couple of Landover forums and it appeared that the noise was more likely to be the pump. But not wanting to spend money I didn't need to I bought a stethoscope that has a metal pointer that allowed me to listen to the pump and it was obvious that pump was to blame.