Back to the drawing board :(

D.Slatford · Post by **D.Slatford** » 21 Sep 2005, 15:41

Well, the aircon lasted almost a week after the compressor was replaced.
This morning it won't turn on. I assume it's low pressure. It did seem to be getting less cold day by day.
I've a gut feeling if it's leaking from anywhere then it's likely to be around the evaporator. I noticed that after having had the system running for a while before parking up, then later on there'd be a rather unpleasant smell from the vents. I presume, gas escaping through the seals?
Where abouts is the evaporator - is this going to be a whole dashboard out job get to it?

Kowalski · Post by **Kowalski** » 21 Sep 2005, 18:02

The evaporator is behind the dashboard, in front of the passenger footwell.
I have a leak on my air-con system and was wondering whether removing the glovebox and its surround would give good enough access to work on evaporator, looks like somebody might be about to find out for me! The glovebox has to be removed from its surround first, I'm told it can be removed by removing the screws that hold it to its hinges, these screws are hidden inside the glovebox underneath its carpet liner (which is glued down). If you feel about in the glovebox, you'll be able to feel where the screw holes are. Once you've got the glovebox out, you'll be able to remove its surround, which as far as I can tell is held in by 5 screws, 3 at the top (there are 2 more screws up there which hold the catches to the box and don't need to be removed) and another 2 screws at the bottom plus a couple of clips.
I picked up a good air-con leak detector off ebay for under £13 delivered, there is a similar one right now 7546625458 at £5 with 8 hours left, they're pretty simple to use and will confirm whether the leak is in with the evaporator or not.

D.Slatford · Post by **D.Slatford** » 21 Sep 2005, 18:18

<blockquote id="quote">quote:<hr height="1" noshade id="quote">
I picked up a good air-con leak detector off ebay for under £13 delivered, there is a similar one right now 7546625458 at £5 with 8 hours left, they're pretty simple to use and will confirm whether the leak is in with the evaporator or not.
<hr height="1" noshade id="quote"></blockquote id="quote">
Thanks for the link, I'll see if I can swipe that. How do these things work, it surely can't magically tell me where the leak is?

fastandfurryous · Post by **fastandfurryous** » 21 Sep 2005, 18:55

Refridgerant leak detectors ususally work by "sniffing" the air, and detecting refridgerant gas in it. You waft the probe around your A/C system, and when the detector starts to go bonkers, that's where the leak is.
Best used when there is a very light breeze, and you're best starting upwind and working down, as the sensors can be very sensitive, and give odd responses if there is refridgerant in the air already.

Kowalski · Post by **Kowalski** » 21 Sep 2005, 22:00

<blockquote id="quote">quote:<hr height="1" noshade id="quote">Originally posted by D.Slatford

Thanks for the link, I'll see if I can swipe that. How do these things work, it surely can't magically tell me where the leak is?
<hr height="1" noshade id="quote"></blockquote id="quote">
Leak detectors are pretty straight forward to use. The TIF one I've got (similar to that one on Ebay) has a sort of heartbeat i.e. it beats all of the time, when it detects refrigerant the beeping gets higher pitched and quicker. They're very sensitive, if you've got a big leak, the leak detector isn't very useful (it'll detect that there is a leak but can't tell where exactly it is because the refrigerant diffuses through the air from the leak and the detector can pick it up some distance away, thats why it can be handy to have a slight breeze as FF mentions above.
The probe on mine has a fan in it which sucks the refrigerant onto the sensing tip, if a leak is very slight it will produce a detectable cloud of gas around the leak and you'll come along with your probe and it will suck it all up and detect it then it can go quiet again, if the leak is very slight you won't want any wind at all.
Its a bit fiddly and you may get false positives on your way to finding a leak with a detector, but I'm sure you'll work it out.

JohnT · Post by **JohnT** » 21 Sep 2005, 22:07

The easiest way to detect the source of the leak is to return to the people who put the gass in and they will add another gas with a dye that can be picked by an ultra violet lamp. Most leakes come from the exchanger/condenser areas.

D.Slatford · Post by **D.Slatford** » 21 Sep 2005, 22:22

<blockquote id="quote">quote:<hr height="1" noshade id="quote">Originally posted by JohnT

The easiest way to detect the source of the leak is to return to the people who put the gass in and they will add another gas with a dye that can be picked by an ultra violet lamp. Most leakes come from the exchanger/condenser areas.
<hr height="1" noshade id="quote"></blockquote id="quote">
Indeed, but that sounds like more money. I'll give this a try (at least I hope it's not gushing out the compressor, it was second hand and sat in a box for a few weeks) although preparing myself to take out the dash soon - or with luck just the glove box. The sour smell that blew out the vents after the aircon had been on was a concern right from the start.
If it turns out to be from the condensor I'll just give up and sulk for a few months - I tried to remove the rad/intercooler/condensor before and failed miserably even unplumbing the rad through lack of space.

JohnT · Post by **JohnT** » 21 Sep 2005, 22:30

If that smell from the vents is a bit of a curry flavour I suggest you check the heater matrix as well while you are under there. I have replaced two of these, one in a jag and one pug and that smell is very evident! (I had expected a No27 with curry sauce to have dribbled down the vents).

xantiav6 · Post by **xantiav6** » 22 Sep 2005, 01:16

If the leak is big enough to lose all your gas in a week, then it should have taken quite a bit of compressor oil with it. Look around all the piping and the compressor for an oily patch.

D.Slatford · Post by **D.Slatford** » 22 Sep 2005, 19:25

Well, I've had a closer look. This morning, while the compressor didn't turn on, the radiator fans still did... and the dryer sight window is still full of green. So, looks like it isn't down to too low pressure, but something else was preventing the clutch from kicking in.
Checked it just now. It worked. Turn aircon on, few seconds, and fans kick in, clutch engaged, cool air (but by no means freezing), and lots of green whizzing past the sight window. Is there any normal explaination for this? It feels like an intermittant fault.
When the aircons turned off, three or so bubbles seem to have settled under the sight glass. Is this refridgerant gas or air getting in?
However, it is slowly dripping green fluid off the bottom of the compressor, right around the middle

So I guess it's only a matter of time before it dies completely - I take it that wouldn't be repairable? The compressor otherwise looks almost new.
I got the gas detector off ebay, will poke that into places when it arrives.