Air con evaporator

[greeban]

I have a 1995 celebration and was disappointed to find that the evaporator is leaking. According to the air con engineer, Jaguar fitted inferior a/c parts in the later models - just my luck! No doubt they did this to save themselves some money - not that I can blame them as they were close to the wall. Shame it is such a bu**er to replace.
I have to remove all the dashboard and the part alone will cost £s so there is no way I can afford to have a garage do it.
I have the manual on CD so can see how it is done - just wondered if there is anyone out there who has experience of removing the dashboard and can provide some pointers?

I am also interested to find out if anyone else has this problem - particularly if you own a celebration. Is there a trend here?

[dhdove]

Hi Graeme,
I have an older XJ-S and can't comment on the quality of the newer kit, however having done some work (and paid others) on getting my own air-con sorted (nearly) and having read the mags over the years i think that you should steel yourself for a big job..........you are quite right that you will have to strip out the air-con assy complete which will involve removing most if not all of the front "dash" area of the car.ouch!
I can't add any expertise to the factory advice re removing the dash , but do be aware that if you are referring to the Jaguar factory xjs workshop manual, it is, in my experience notoriously incomplete or innaccurate, at least on the older cars. You may well find that what is shown in the book is not what you've got.........it all adds to the experience!
Don't forget to label EVERYTHING as you disconnect it as you will have a panfull of spaghetti by the time its out.
NB when carrying out this work do be very careful when removing the expansion valve as these are very easy to break and not easy/cheap to replace.
Sorry I can't be more positive, but this is a BIG job.
Good Luck
DH Dove

[greeban]

Thanks for the reply - is it possible it could be the expansion valve and not the evaporator. I was going to go ahead and buy the evaporator as David Marks says they may become short in supply but now I wonder if I should wait until I get the whole assembly out.
I presume someone can test it once it is out?

[dhdove]

Graeme
As I understand it you have been advised that the evaporator is LEAKING, presumably the system does not hold pressure under test and they have identified the EVAPORATOR as the culprit, is this the case?. If it is then the evaporator or its connections is u/s and will have to be replaced.
The expansion valve regulates the flow of high pressure gas into the evaporator which then expands in the low pressure environment and absorbs heat, I guess this item could be the source of your leak, but your air-con people would have told you?
XJ-S (or XJS!) air-con in my experience is a bit of a black art, everyone seems to know a bit about it but nobody seems to have the full picture. I would guess that Dave Marks is probably one of the best informed. Did he do the diagnosis?
Regards
DH Dove

[greeban]

It was not Dave Marks I'm afraid - I had the car in at a jag 'specialist' in Bedford who called in an air con engineer who I do not know. I was told when I picked the car up that the leak could be heard with a stethoscope through the front air vents and so it is very likely the evaporator is leaking.
I am wondering now if I need a second opinion as I had not realised that there is another link in the chain. I had assumed it was one complete unit inside the car and so requires evaporator replacement.

[dhdove]

Graeme
If leak can be heard in the air vents I would guess that it probably is the evap. that's leaking as the expansion valve only feeds gas into the evap. It's located through the bulkhead from the engine bay into the evap. Open the bonnet, at the centre of the bulkhead about three inches down you should see the end of the Exp. valve sticking out a little directly in front of the air con unit. This valve regulates the flow of gas into the evap. and includes a temperature monitor (looks like a long curled pigs tail hidden inside the evap. that feeds into the evap unit and shuts off the flow of gas if it detects it is (literally) freezing. I understand from articles I have read in the past that if this fails your evap. resembles a domestic freezer with a broken door ie wall to wall ice - and all that water has to go somewhere ie into your car if the air con drains are blocked........if the weather is humid you would be amazed how much water is produced!
Im not sure where this leaves you,- live with the problem or
1 spend an amount of money- who knows how much? to get a competent firm to sort it
2 take the stripdown on yourself and be prepared for the downtime on your car as you climb the learning curve
I chose option 1 as I need my car in everyday service. Initial diagnosis, secondhand but as new condenser fitted myself, new receiver drier fitted myself new compressor, new regulator valve, couple of regas and degasses COST @ £750.00ish NB I did not remove any of the interior for this, this was all forward of the bulkhead work.
I would suggest that you get a professional assessment yourself before proceeding, as you can see the costs can be high and unfortunately one thing leads to another. I found that once you've spent a few hundred quid and it's still not right you tend to carry on to the next step..........
Best Wishes
DH Dove

[Mark_B]

you can see that fluorescent dye better with UV light for example one of those lamps for seeing invisible security marker. the pros use a more intense mercury light and green goggles

[dodgy]

Hi,

I have some pictures re the leaking evaporator already on my web site (see below) but I have yet to write up the evaporator replacement bit. I will do when I get time.

See Homepage

Roger

[greeban]

This is great - I for one will welcome any more pictures and/or description of the process that you can provide. Was there anything in removal that you found particularly difficult, any special tools needed?

[dodgy]

Hi

Just an update, after I replaced the evaporator last year it worked for around 9 months. I can see leaking AC dye around the expansion valve block. I did replace the o'rings during reassembly. I got them from a Jaguar main dealer however they managed to find them in a bag so they could have been years old. I just this week had them replaced and the AC regassed so I am cool for Le Mans !
I'll see how long this lasts however it has not shown any dye from any of the other areas and this was the only area I touched so fingers crossed.

Cheers

Roger

[dhdove]

Dodgy
Good news, good luck with that, hope it is the o-rings and not the expansion valve
Graeme
Any news on your problems?
DH Dove

[greeban]

Hi,

I have a new evaporator so looking to take the car off the road for a month or so soon and get on with fitting it. It does get very hot without a/c! Having spoken with an a/c engineer who is fixing my Galaxy's broken a/c ( long story and will not go into it now!), he says no problem with my fitting the evap as all the pipwork is in the engine bay so he can sort any leaks that may occur once I get it done.

If anyone has any more pictures/ experiences to share for removing the evaporator I will be most grateful.

[dhdove]

HI Graeme
Don't ground your car before 2nd July, are you coming to the racing at Cadwell Park
NB You say its too hot, are you getting ambient temp. air from the vents? ie coolish/warm this weather? Or is it HOT? You may be able to turn off the heat if thats what you've got by turning the system on and turning the heat control right down, if the flaps are working this should cut off the heat and give you ambient air , the faster you go the cooler it gets!
Apologies if I'm teaching the goose how to suck eggs!
Best Wishes
DH Dove

[greeban]

Hi DH,

Not sure I can make cadwell but am hoping to get to father's in the park at Knebworth this Sunday which is next door to me!

Thanks for the advice on the heating - it is ambient, just that I can feel the heat from the transmission/exhaust when I rest my leg on the tunnel! It is quite cool too having the windows down and enjoying the pillarless doors. Excellent!

[fiddler]

Had my recently acquired 1993 4.0 Conv.out at the w/e. After 2hrs ish gurgling noise from air vents followed by a stream of clean water into, mainly, the passenger wheel well. I am new to all this but the air con still seems to be working (it was in MAN at the time) Do the drains get blocked easily and where are they to unblock them? I hope it is a simple solution, the previous posts have frightened me a bit...... a lot actually! Any thoughts gratefully received.