Z928328

Please list me the possibility of leakage.

The other I sent my car to a Aircon specialists & they just refill with gas & the car AC is cold. That night it only blows air.( Not cold air)

Yesterday, I sent my car to the same shop- This time they check for leaks & there's some worn out seals. Pics below:
1)- They recommend me to change but they do have one in stock.

What part is this called? They do not have it in stock & they use it back & replace the worn out seals which they suspect is the culprit.

The worn out SEALS: Whic they replace.


What hose is this?


The GTS tubes-Looks old- I'm ordering one set from Roger- The plastic ones like for the S4.


They say- If my 928 still lose out cold air- that means only one thing left to check since they are no leaks from the engine- The cooling coil located in the dashboard which require them to open up the car dash. Please confirm that with me.

Also I follow FredR advice on checking the compressor seals which they said it's still OK. I'm surprise the compressor is Denso with the Japanese marking.

So please advice me on where it could leak?
Possibilities
1) Cooling coil
2) ?
3) ?

Please list me the possibility. They check all the hoses in the engine- No leaks at all.

Z

Asiandude

Besides the cooling coil (evaporator in dash):
The expansion valve (just infront of the evaporator box).
The condensor radiator (front of car).
Receiver dryer (that's the cylinder in your pic) and/or either of the switches attached to it.
Any of the hose connections.
The compressor.
On my S4 I've replaced (so far) the evaporator, expansion valve, pressure hose and icing switch. Living in the tropics aircon is a must have!

JHowell37

If it's leaking out that fast, you should be able to hear it.

I believe the hose in the picture is the low pressure hose. I'm wondering why it's deteriorated like it is.

Z928328

^^ Yes- The hose looks terrible & it's still usable.

Asiandude,

Yes they check everything: The hose connecting the AC etc.
Ahh.. It's called the dryer- They even mention it- Well they just change the SEALSon the dryer which connect to the switch & used back the old dryer. I hope that is still the culprit.No need to open up the dash etc.

They took it out & check it-No sign of leakage.




Where is this? Where the evaporator box located?

Where do you get all your AC parts? & where is the icing switch?

Thanks

Z

Nicole

Did your technician put any fluorescent dye into the system? That and recharging the system, then running it for a few minutes should reveal where the leaks are.

If there are no leaks outside of the heater box, here is how to peek inside: Remove the black plastic cover in front of the windshield. Shift the rubber boot that connects the blower housing with the heater box, and peek inside. The opening is big enough to get a dentists' mirror inside, so you should be able to inspect at least one side of the "Cooling coil", orevaporator.

If the evaporator in the heater box leaks, you are looking at a major project. I had this done on my car, and there were at least two days of labor involved, if I remember correctly. The original part is around $800, but there is a place in Germany that sells them for about half that.

This is also a good time to replace all vacuum actuators - if you order stuff from Roger, ask him about those!

Jadz928

Don't forget to check the large flare fittings on the fuel cooler, located on the firewall (right behind the air filter box).

What Nicole said. Dye in the charge, and also a freon "sniffer".

Z928328

Thanks for the advice Nicole. Will note it down.

I don't think they use any fluorescent dye.They did get it running & use their skills( Not sure how they did it ) to check & there's no leaks.

But they did mention that the cooling coil will takes at least one whole day or two. I have to supply them the parts. I already Email Roger for the parts list.


If its that expensive- I will just order the parts needed like the timing belt & stuff from Roger & the AC parts maybe next month from him. The fresh air is good . As for now- I only drive around town nearby under 2k RPM. Hehehe. The next trip will be to the workshop. Still have to finalized the deal with Roger on which parts etc.


OK .Noted down..
Z

dprantl

Later cars have o-ring fittings there too.

Dan
'91 928GT S/C 475hp/460lb.ft

JHowell37

That low pressure pipe doesn't look like it's routed properly. It's made of aluminum. If it rubs anywhere, it will develop a hole very fast. If it's leaking out completely in just a few hours, you should be able to hear a hissing sound with the engine turned off.

Z928328

^^I did hear that sound when switching off. Like "ssssss".... I thought it's normal. So it's the low pressure pipe?

Z

SeanR

As stated already.

1. Drier and seals
2. Expansion valve and seals under the cowl, located by the wiper motor.
3. Compressor seals
4. hose seals
5. If you have rear air, expansion valve/seals
6 connections under the car for rear a/c. some seals and two hardlines.

JHowell37

Some hissing is normal when you shut it down (immediately afterwards.) But if it's hissing 10 or 15 minutes later, that's not normal.

I don't know if your low pressure pipe is leaking. All I'm saying is the routing for it looks to be incorrect, and I also wonder why it's wrapped in that black hose that looks like it's breaking down. I don't have a GTS so I don't know how the pipe should be routed.

A/C leaks are not something you can really diagnose from a distance. But I can suggest the cheapest course of action first.

Replace every o-ring in the system. Replace the drier. There will be an o-ring at every single connection in the system. If a couple are bad, it's likely that more will be bad (or possibly weak.) After you do that, vacuum the system, if it can hold vacuum, charge it. See what happens.

Z928328

^^OK then. I hope it's not the "cooling coil" which is USD$880! from Roger. The hissing sound is right after I switch off the engine.

I will paypal Roger later in the morning & can't wait for all the parts(Drier,TB, tubes etc) to arrive.( Takes a week or two to arrive here).

Z

Nicole

When my evaporate under the dash leaked, I heard a constant hissing sound through the center vent when the AC was on. As soon as I turned off the AC, the hissing would start to fade until it stopped. That happened until there was not enough freon left to pressurize the system.

WallyP

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