Air Con Squeal

[gmax333]

I am having a problem with my air con however it's a problem that doesn't happen all the time (mainly just when its really warm).

When the air con comes on and the problem is present i get a squeling noise which comes and goes. Whilst the noise happens you can feel the engine loosing power. The problem appears mainly when its more than 18oC ambient. Over the last couple of days because its only been 11-14oc the problem hasn't really happened.

When the noise appears you can see the autotensioner on the engine react - it appears to judder from side to side.

Anyone any ideas? Cheers

[gmax333]

The aircon was re-gassed at Nationwide who said there were no leaks about a month ago. This problem has been there since then (the air con hadn't worked when i got the car).

When the noise and pulsation from the engine isn't there the system works fine and produced very cold air.

[T-Cut]

When the noise appears you can see the autotensioner on the engine react - it appears to judder from side to side.

Intriguing. Could you describe this autotensioner or post a photo?

TC

[gmax333]

Intriguing. Could you describe this autotensioner or post a photo?

TC

Yes - i'll try and get a short video of it i poss to when the problem happens. This tensioner is between the bottom pulley and the air con pulley from memory. It makes a tinkling noise like its has a spring in that is about to fall off.

[kevin]

This could be what I had on a mates Vaxhall and needed a new tensioner for the fan/ac blet.
we could hear a noise but could not find where it was coming from rac man had help the tensioner had fell to bits after a 200miles drive.

only fould out after it came home on the back of a RAC van.

when was the fan blet and tensioner last changed.
what is the mileage of your car.

If you put where you are some one near may be able to help you.

[T-Cut]

I does sound like the auxiliary belt tensioner. When you switch on the A/C, the compressor is connected to the belt drive by an electric clutch. This places extra load on the belt/engine and could account for the noises you hear.

I think this is the part you may need (Rimmer info):

Part Number PQG100190
Description TENSIONER-AUTOMATIC ANCILLARY DRIVE
Retail Price £137.80 inc. VAT (£119.83 exc. VAT)

TC

[gmax333]

I am based near Doncaster. The car has done 100k however the last owner said the engine was replaced and the cambelt / headgasket replaced however I have no idea how many miles this replacement engine could have done.

Thats an expensive part, though suppose its better than being the air con unit itself.

ta

[gmax333]

I have uploaded the following video. Zoom in at the part that has been rattling about before, however not today - typical.

http://www.youtube.com/watch?v=siOYRohadIs

I notice that the squealing is only audiable from inside the car, not sure why it is. In the engine bay I notice that the compressor is coming on and off often (every 10 secs).

[JohnDotCom]

I take it the Fan is working OK and correctly?

[Phil]

If the fan is working, the compressor coming on and off quickly will cause the tensioner to move, I can't help wondering if the a/c system is actually overgassed.

[gmax333]

The fans come on full speed when the air con is on, however I am not sure they are when the compressor switchs off.

[JohnDotCom]

If they only run at full speed you either have a faulty Fan, if 3 speed fitted
or a faulty resistor if 2 speed fitted by the sound of it.

[gmax333]

If they only run at full speed you either have a faulty Fan, if 3 speed fitted
or a faulty resistor if 2 speed fitted by the sound of it.ink

They come on at first and make lots of noise, after a while they slow down and make less noise, i think.

I took the car back to the garage this morning however they said they wouldn't be able to look at it today (d'oh). I mentioned about the overfilling of the gas and they said all they did was plug it in to a computer and it did the rest, and that the only way they could overgas was if the system had some gas trapped inside.

Do all 75's use the same amount of gas? Can air get trapped in the 75's system.

Cheers for your help everyone.

[T-Cut]

Do all 75's use the same amount of gas?

Yes. Details on the yellow sticker on the slam panel.

Can air get trapped in the 75's system.

Not if there's any refrigerant in there because it's at higher than atmospheric pressure. In a completely empty system, I suppose air could diffuse in through the leak point. However, a computerised refilling machine should evacuate the system to ensure there's no residual air/moisture left befaore recharging.

TC

[gmax333]

Took the car back to Nationwide today and the had overfilled it. They recovered about 700g. He said there must have been a pocket somewhere that had got stuck as it wouldn't keep vacuum at at first.

In the end they managed to refil with 450g and it now works, yay.

[Phil]

Thanks for getting back with the cure to your problem.:)