Air con problem-help please

[tag13]

Firstly let me say I know how to lift the bonnet... and thats about it... so please be gentle with me......

I have recently bought a 2002 Terrano and on driving home to France on the hottest day of the year realised that the air con doesn't work!
I have all the SH with the car and invoices. On reading the service invoice from last August it says they checked the air con system and there was a leak that means a new pipe is required....cant see that it was done though.
Now thats all the info I have on the problem. Can someone advise me how to decide what part I need please. I don't want to get a re-gas done if they never fixed the pipe. Also, trying to explain in French that I have a leak from somewhere isn't going to be easy.

I know it's a long shot but any advice would be greatly appreciated.

 

[jims-terrano]

A couple of weeks ago someone posted with a photo of a leaking AC pipe, have a look and see if you can find it as the photo is quite clear. As far as I can remember it is on the front panel near the radiator, it seems to cored under a clamp. Shame your not over here as Kwikfit will regas your AC and not charge you if it leaks, having them regas it may show your leak.

Jim T

 

[Deleted account DD]

Dont know if its my air con ramblings you mean Jim but all my related pics are located here http://picasaweb.google.co.uk/daveditch/TerranoPartsII#

The specific one may be this one where you can see the fluid coming from the top pipe.

 

[jims-terrano]

Spot on DaveD

Jim

 

[tag13]

Thanks will have a look under bonnet today.
If I find it though how will I know where the leak is if there is no gas in it? Obviously if it had a leak in August '08 its not going to be still leaking now is it so how will I tell??

 

[Deleted account DD]

The bit you can see behind the rubber sleeve and the bracket suffers from stress fractures and is a common pint of failure (I'm told :bow).

On mine before it went altogether it actually passed the pressure/vacuum tests, took a full charge which lasted 24hrs then gave up the ghost.

If I were diagnosing it again I would peel back the rubber and see if theres any sign of leakage behind it. Mine had been leaking for a while but the rubber had acted a bit like a sticking plaster and was well gummed up inside.

Yours may not be leaking there of course !!!!

I would have a good look under the bonnet and follow the air con lines looking for the leak. Nowadays they pt dye in like the green you can see on mine. In the past they've sometimes put a UV dye in so you'll need a fluorescent lamp to search for it.

If you spot it :thumb2 great, its time to repair.

Perhaps before doing that or if you cant see a leak what I would do and its not a recommended service technique is check the pressure (I'm not sure if the refrigerant is toxic but you wouldn't want it on your chips ! ).

If you look on the photo where the blue cap is, that's the charging point. its a schrader type valve, same principle as your tyre valve. As a rule of thumb if the valve is depressed and there's enough charge in there to allow the air con to run, it'll hiss, if its too low and the systems switched down you'll get no or a weedy little hiss. If you do this be very careful.

The charge does deteriorate over time so your options are it needs charging due to "natural wastage" or you have a leak and its escaped.

Bit of a circle to go around but not too difficult. Good luck :thumb2

 

[tag13]

I have found the pipe, and undone the bolt that holds the bracket where the rubber sleeve bit it. The rubber is one piece and is pretty much stuck to the pipe. I can see under it there's a bit of what looks like white limescale and a small green dot on the pipe.Nothing like the obvious signs on the photo though. How do I see whats under the rubber sleeve?

Thanks for your patience with me...

 

[Deleted account DD]

Unfortunately is at least semi destructive removal

If there's any green around it I would be suspecting either a leak or they haven't cleaned up after last time. Theres no other reason for the green stuff to be there the charging point and unions are all "dowhnill" from it.

Have you got a pic?

 

[tag13]

Not sure if you can see the very small green dot..

Also this has bugs and things in it and I wondered if that wouldnt be helping...do I need to clean it?

 

[Timbo_1975]

That dot indeed looks like it could be a leak, difficult to tell without at least putting a vacuum pump on the system and checking with a dab of PAG oil on it. - Better than wasting a charge of gas.

Looks like yours is a 2002> car without the supplimentary condensor fan? A careful clean with a power washer aimed directly at the core not too close would probably help, but i have seen worse....

Regards, Tim.

 

[Deleted account DD]

Tbh I cant tell much from the pic, it doesnt look too bad but on mine I couldnt see anything wrong at first

Is there any pressure in the system?

 

[tag13]

I'm a bit scared to test the pressure like you said....maybe I can find a man to volunteer to do that!

I was think of using the blower bit from our air compressor to blow the flys out (sorry dont know the technical word)

 

[Timbo_1975]

I would not recommend depressing either of the schraeder valves, as if there is refrigerant in the system and it lands on your skin (or somewhere worse) it will burn severely.

Get someone to hook up their gauges instead. Even on an apparent dead system, there can still be 30+psi present.

If the system is infact empty and has been for a while, you'll need to change the drier at the least, as it will be saturated with water.

 

[Deleted account DD]

I would not recommend depressing either of the schraeder valves, as if there is refrigerant in the system and it lands on your skin (or somewhere worse) it will burn severely.

Thats why I said "I would" ie my risk as always when recomending work I actually have a cheepy gauge to check the pressure. Basic h & s is to wear gloves anyway when dealing with chemicals and of course you dont have to depress the schrader fully on a manual test.

for your info (from wilki):

"Contact of tetrafluoroethane with flames or hot surfaces in excess of 250 °C (482 °F) may cause vapor decomposition and the emission of toxic gases including hydrogen fluoride and carbonyl halides.<sup id="cite_ref-10" class="reference">[11]</sup> Tetrafluoroethane itself has an LC₅₀ (lethal concentration for 50% of subjects) in rats of 1,500 g/m³, making it relatively non-toxic. However, its gaseous form is denser than air, and will displace air in the lungs. This can result in asphyxiation if excessively inhaled.<sup id="cite_ref-11" class="reference"></sup><sup id="cite_ref-12" class="reference"></sup>
Aerosol cans containing tetrafluoroethane, when inverted, become effective freeze sprays. Under pressure, tetrafluoroethane is compressed into a liquid, which upon vaporization absorbs a significant amount of thermal energy. As a result, it will greatly lower the temperature of any object it contacts as it evaporates. This can result in frostbite when it contacts skin."




With care no problem, but the choice is the users :thumb2 I've worked with worse but if in doubt go to your local garage.

 

[Deleted account DD]

Sorry should have made it clear, the big blue cap I stand corrected if thats not the lp side on these cars.

Just for info, I've had a look for my gauge cant find it so i've just pressed the schrader with a bbq skewer ( I know its fully charged at present) lots of resistance and a little bit of dye.

No problems.


I do suspect on yours tag you'll get little to nothing just be very careful.

 

[jims-terrano]

I'm a bit scared to test the pressure like you said....maybe I can find a man to volunteer to do that!

I was think of using the blower bit from our air compressor to blow the flys out (sorry dont know the technical word)

Use the compressed air line blowing from the engine bay out so that it blows the debris out the way it came if you know what I mean.

If your unsure at all about the AC Gases then I don't blame you at all, take it to a AC Service Engineer and point out where you suspect the leak.

Jim T

 

[tag13]

Just to update you...
A friend came round and with a can of air con stuff we managed to find the leak in the pipe...which was what the garage originally said the problem was. Took car to Nissan in Limoges and they wanted 97€ for a bit of aluminium pipe, then with fitting it and regassing it came to a cool....300€, so I said au revoir!

Went back to friend who made up a pipe from copper, got some correct fixings as the original was cross threaded-cost,5€. Took to small garage today for full air con service and regas,89€. So I'm 200€ in pocket from not getting Nissan to do it and its working brilliantly. Thanks for the advice chaps!

 

[zippy656]

see tag told you!

friendly and helpfully

 

[Deleted account DD]

Excellent :thumb2

 

[jims-terrano]

Good news:thumb2 Just out of interest where was the leak?

Jim T