124 AC problem

[Motard]

In January I had to drive my 124TD to the UK to pick up a load of things. When I was there Ian Walker arranged to have my AC topped up. My AC has always worked but only just. The guy Ian booked me with, Stuart McHugh, did a first class job, explaining what he was doing and interpreting the readouts on the LCD screen on his machine. He drained my system then checked if it would hold a vacuum after which he refilled it with new oil and refrigerant
Apparently my system was in pretty good nick, Stuart certainly seemed to be meticulous in what he did and I drove away a happy man.

It is warming up down here now, rather later than usual but we are getting there. The other day the car had been stood in the sun so I put the AC on expecting to be frozen solid within seconds…..it didn’t happen! Clearly the AC is working but there doesn’t appear to be any real improvement on how it was before.
I called Stuart but he couldn’t offer any ideas other than that he thought it unlikely to be a mechanical problem as the system tested so well.
Ian told me about the sensor hidden behind the interior light so I removed that and cleaned is as best I could, again no change!
Any ideas anyone? All help will be gratefully received.

 

[Subyland]

My 124 is the same, it takes some time for the AC to cool the air down. I have spoken with a couple of 124 owners as well and they've told me exactly the same...so may be it is normal on a 124 as the system is quite old in design ??

 

[MangoMan]

All I can say is, is that when mine was working, (it has a leak somewhere now), it used to get pretty damn cold, pretty damn quick. But then I lose all my gas in about 4 days, and then it won't even switch on.

Ciao.

 

[bolide]

W124 a/c

Is the compressor kicking in or not? Shine a torch down in the engine bay and watch the centre of the a/c compressor. The outer pulley spins all the time - it has to, it's on the serpentine belt - but the inner only spins when the compressor is active

If it's cutting in, and not switching off again immediately, I'd expect you to have cold air. If it's not cutting in I expect you have lost the refrigerant. There's a sensor on the low-pressure side of the circuit that prevents the compressor kicking in if the pressure is too low. Normal reason for pressure too low: lost gas. Normal reason for lost gas: stone damage to condensor

You might want to try reseating the sensor connectors. They're on the pipework on the (UK) passenger side just above the chassis rail about 3" behind the radiator

Nick Froome
www.w124.co.uk

 

[Motard]

Thanks for the response guys.

All I can say is, is that when mine was working, (it has a leak somewhere now), it used to get pretty damn cold, pretty damn quick. But then I lose all my gas in about 4 days, and then it won't even switch on.

Ciao.

I had the same experience with a new 124 I owned way back when.

Nick,

Thanks for the suggestions.
I am sure the compressor is working as there is a blip in the revs as it kicks in and the air coming out is definitely colder than the ambient. Tomorrow I will stick a thermometer in and see what it reads. At the same time I will watch the compressor pulley and see what it does.
Reseat the sensors? I would love to If only I knew what they looked like and how to reseat them
I doubt there is a leak. When Stuart worked on it in January it hadn't been touched for at least 3 years and there was still enough refrigerant in to cool the car in summer. If my memory serves me well he held it on vacuum for 30 minutes and it was pefect.

Bob

 

[bolide]

Chillin'

OK, if it's a 250TD and the aircon works, throw it along a Route Nationale for 35 minutes at 90 mph and see what happens. Mine used to chill so-so, but when you cranked the car up to speed it got colder & colder

I did a trip from Cahors up into the hills, 4-up, at about 11 am one summer. You could feel the heat through the windows but, at speed, it was great. When we got out, in one of those little hill towns with a market full of very cool hippyish bearded French, the heat hit you like a hammer. Just had to sit and drink coffee for a couple of hours..

Nick Froome
www.w124.co.uk

 

[MangoMan]

Just had to sit and drink coffee for a couple of hours..

Nick Froome
www.w124.co.uk

What!....Only Coffee...!!!!....

 

[Motard]

OK, if it's a 250TD and the aircon works, throw it along a Route Nationale for 35 minutes at 90 mph and see what happens. www.w124.co.uk

MMMMmmmm, a couple of problems with that! Maybe you forgot that to check the 0-60 time on a 250TD one uses a calendar so that would mean a VERY long Route Nationale Add to that the fact that doing that nowadays could end up with getting nicked. 144kph in a 90kph limit....English..... definitely bring back the guillotine
However, took the thing out this morning, checked the compressor is kicking in OK by watching the pulley as Nick suggested, then went shopping with it. Definitely cold air coming out of the vents. When I returned I left it ticking over and stuck a small thermometer in the vent. Maximum cold setting without AC came to 25c, switched the AC on and it went to 10c very quickly at which point I had to leave it to do something else.
So, it looks like I may have been having a 'bald' moment, similar to a 'blonde' moment only worse according to my teenagers
Thanks guys!

 

[bolide]

30 mins of acceleration, 5 mins at 90 mph

MMMMmmmm, a couple of problems with that! Maybe you forgot that to check the 0-60 time on a 250TD one uses a calendar so that would mean a VERY long Route Nationale

That's what I meant - 30 mins of acceleration, 5 mins at 90 mph. Gotta love the 250TD!

Nick Froome
www.w124.co.uk

 

[Motard]

Went out yesterday with the small thermometer sitting in the central air vent. Coming back was a 20 minute run at 60mph, checked the thermometer...4c! Exactly as tested when overhauled!
Now I will crawl back into my shell...........

 

[Ian B Walker]

Another bald Moment then Bob?