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Discussion Starter · #1 ·
Came home today and parked up, got out the car and heard a very obvious hissing noise from the front end.

Now since it's the UK, I think I can discount it being a snake trapped in the bumper, so I've concluded it's probably AC gas escaping.

It's pitch black outside otherwise I would've pulled the bumper off to try and hear where the noise was exactly coming from, so I'll probably do that tomorrow. But before I start on it, does anyone have any advice as to what to look for/common areas (if any) where I'd find a leak?

There was a crude smell around the area, and no obvious liquid on the ground, so would my assumption of AC gas seem plausible?

If I do find the leak and it's in the condenser, can I use some liquid metal epoxy to patch it up or is that unlikely to hold?

TIA as always.
 

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Seeing as the company I use AC guys use all sorts of kit to check for leaks, I'd be very surprised if ears were good enough to hear leaks. They refilled my old Jeep A/C 4 times to check for leaks (all on the same day) and eventually using some leak detector/sniffer/gas found it.
 

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Discussion Starter · #3 ·
Sounded kind of like a tyre deflating, but if it's not AC then I've not got a clue what it could be. Car wasn't running hot, so I don't think it's coolant boiling over.
 

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AC leaks are normally tested at time of regassing...
There is, or used to be at least - it might have changed, a dye that would show any leaks under uv light..

Not sure there's a DIY way...

Get you ear-ole in there....

As for patching... Probably not a good idea.
Never heard of it being done, always known it to be a case of replacing parts or leaving it empty.

Happy to be proven wrong, not an AC whizz just picked a few bits up - as you do.
 

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Rubber piping running across the front of the engine bay has a hole in it. Squeeze it to find out. How to fix? No idea as part no longer available...

Or one of your aluminium pipes has a crack or a schaeder valve is leaking.

Get some UV dye in the system if you can't see where it's leaking from.
 

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Discussion Starter · #6 ·
AC leaks are normally tested at time of regassing...
There is, or used to be at least - it might have changed, a dye that would show any leaks under uv light..

Not sure there's a DIY way...

Get you ear-ole in there....

As for patching... Probably not a good idea.
Never heard of it being done, always known it to be a case of replacing parts or leaving it empty.

Happy to be proven wrong, not an AC whizz just picked a few bits up - as you do.
Thanks, good idea, I'll get a UV light on it just in case there was any dye put in when it was last regassed, I heard that some AC guys put it in anyway as a proactive measure in case any leaks present themselves.


Rubber piping running across the front of the engine bay has a hole in it. Squeeze it to find out. How to fix? No idea as part no longer available...

Or one of your aluminium pipes has a crack or a schaeder valve is leaking.

Get some UV dye in the system if you can't see where it's leaking from.
Thanks. Rubber piping sounds like the most likely culprit here, a quick glance shows that the pipes have cracks appearing, and the sound was just very similar to air escaping a tyre.

I haven't had a chance to pull it apart yet, but assuming it's a pipe then I'll chance getting a second hand replacement if new is unavailable.
 

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Discussion Starter · #7 ·
Turns out it was very easy to find, one of the crimped ends of a hose had split on the actual metal crimped part so the rubber wasn't sealed in the joint. Second hand pipes seem to be ranging from £15-£50.
 

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Discussion Starter · #9 ·
The smell is quite unique. I mean I've never cut through lines before with a grinder but somehow I know what it smells like.

Glad you found the leak!
Ah yes of course, you must've picked up the smell from working on AC systems that have been properly vacuumed down before they were opened, the smell must've just lingered in the pipes.
 
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