Split two-part AC pipe, C5 X7

[RustyUK]

My 2009 C5 X7 has suffered a failed AC pipe. It's a two-part pipe from the compressor low pressure side, part numbers 6477E9 from the compressor and 647774 from the bulkhead (with the charge port). These both appear to push together and stay attached. Except mine blew apart one day, despite the AC not having been run for some weeks. The system had been working fine up until that.

Annoyingly both pipes run along the side of the engine, with barely room for fingers. I can't find any AC specialists in my area (only re-gassers) who might be able to repair this without replacing all the piping, if that's even an option.

I might attempt replacing the pipes myself, if only to get one or two more summers of working AC out of this car before disposing. I have manifold gauges and a vacuum pump, and have replaced the condenser some years before without issue. Both halves are available new aftermarket on ebay. I have three questions:

Do these pipes literally just push into each other by hand and something grips them together, or does one need crimping onto the other?

The system has been open for about a year (gulp!) - can I expect this to ever work again, or may the oil have absorbed too much moisture by now? I'm hoping that just leaving the vacuum pump on for a few hours might dry it out enough, but I have no idea.

Finally, some amount of oil would have been lost, at least the quantity resting in both replaced pipes. Is there any wisdom on how much I should replace, if any, or can the entire system be flushed out (by myself or someone actually competent) and refilled correctly?

I suppose a fourth question, has anyone else experienced these pipes blowing apart? I can find almost no reference to this happening anywhere.

[mickthemaverick]

I have moved your post to the Citroen forum as you are more likely to get some help here. As an aside I replaced the compressor clutch on my Mk1 C5 which involved complete draining and refilling of both oil and gas. Most regassing companies will have the oil as well as it is almost always needed following a leaky system. I suspect your plan to intensely vacuum the system may dry it out and possibly some gentle heating of the componenets while doing it will help. I am thinking of a hot hair dryer directed at all parts of the system in turn.
You can see the story of my work at: viewtopic.php?p=612544#p612544

[xantia_v6]

The connector is latched by a coil spring that is caught between the inner and outer tubes. They normally lock without difficulty, but unlatching them takes quite a knack.

Putting the system into a deep vacuum will eliminate any moisture from the system, as water has a relatively high vapour pressure, and you can't achieve a deep vacuum while moisture is present. You should of course change the drier, as they tend to disintegrate with age.

I have recommissioned a few old systems, including one that was open to the atmosphere for at least 15 years, without issues (other than aging of hoses). My XJ-S is 50 years old and is still running all original components except for 1 hose, the TXV and drier. It was open for probably a couple of years before I got it.

It is rare for more than a token amount of oil to be added when re-gassing, as 90% of the oil sits in the sump of the compressor and on most systems there is no way of checking the oil level without removing the compressor and draining it.

[Tr7v8]

If your looking for real experts on vehicle A/C then a long way from you but super knowledgeable is https://www.ac4cars.co.uk/contact
They are in Gravesend Kent but people travel far and wide for their help. They sorted my wife's Eunos out when the A/C died, converting it from R12 to a more modern gas & making a condenser fit and re-piping it as spares don't exist. The last time I was in there a guy with an old S-Class Mercedes had come over from Ireland as no one else could fix it. They also had a good reputation amongst the Porsche guys as old Porsches have nightmare a/c issues and no spares availability.

[RustyUK]

Thanks for the replies. I'll give this a go myself, seems I can get both pipes for about £45 which makes it worth a gamble, if I really am supposed to just push one end into the other, the restricted space is still a concern. I'll give this a go shortly and report back how it went!