A/C series III
 

Is anyone out there an expert in air conditioning systems for series III XJs? I'm considering tackling this project on my 86 sovereign, but I have zero experience with A/C systems. The Haynes manual has surprisingly little info on the A/C system. What kind of freon does it take (r-12, R-134a)? What's the most common component to go bad (compressor?).

If anyone has troubleshooted this system with success, any input or tips would be much appreciated.

RE: A/C series III
 

Greetings,

That's a bit of a daunting task for a layman, depending on what the failure was.

See if the compressor is locked up, this can happen when it continues to operate with low refrigerant/ oil level. The '86 has a HSLP switch designed to disengage the clutch when pressure is low, it doesn't always prevent failure. Earlier cars have a superheat switch and a thermal limiter fuse mounted on the compressor, which burns out to prevent clutch engagement.

If the compressor locked up, you will also need to replace the receiver/ drier, atop the radiator. You'll have to remove the screen inside the expansion valve on the firewall, and flush the system. It's good practice, although not alwaysimperative, to replace any O ring for a hose unoin you disconnect.

If the compressor in not locked up, it may be leaking from the hose unoin O rings at the rear of the unit, or from the compressor rear head seal. In the latter case, buy a rebuilt: they are cheap and plentiful. Always include a new receiver/ drier per warranty reccomendations of the rebuilder.

You will have to charge the system to leak test it, a good compressor won't engage unless the HSLP switch is getting system pressure. Use any of the retrofit R134 kits available everywhere, some come with instruction CD's. No need to retrofit any other system components for R134 compatability.

Other common sources of system leakage are the high pressure hose from compressor to condeser, and the low pressure hose from the evaporator outlet. The latter likes to rub against the brake pipe union boltthrough the left inner fender until it is perforated.

If the system is charged but the compressor clutch won't engage, there is an inline fuse holder for the clutch feed behind the right console side panel, inside the car. It's up by the evaporator temp sensor, mounted in a P clip. Beyond that, you have a climate control malfunction, not an A/C problem. That's a whole nuther diatribe.

Blockage on a charged system can occur in the receiver/ drier, or the expansion valve screen. Occasionally the expansion valve fails, and does not properly regulate the evaporator pressure. Diagnosis is with A/Cgauge readings on a recharged system.

If you are going to be disconnecting anything at the expansion valve, evaporator or condenser, be very carefull about not twisting anything other than the hose union you are trying to unscrew.Alot of systems are damaged when siezed fittings are yanked on without a backup wrench on the corresponding fitting. Crack an eveporator inlet or outlet, and it's 10 hours for a professional to replace a very expensive evaporator.

Condensers sometimes develop leaks from road debris/ crash damage, or corrosion. Evident on leak test.

Other than that, it's easy! Keep cool...

RE: A/C series III
 

One footnote, for any readers who are using the previous post for reference: it applies to U.S marketSeries III Jaguar XJ6 '82 thru '87, and XJS models '82 thru '91

The earlier XJ6 has a different receiver/drier, and XJS after mid '88 will have a relocated fuse for the compressor clutch.

RE: A/C series III
 

Skan,you asked for it!

all the info you want to know is available if you only spent $25.00 on the Factory Shop Manual CD. Forget about Haynes manuals man, you could have purchased the real thing already. aarrrggghhh!

I'm not an expert. I was so frustrated back in 1998 trying to get my system (Delanair Mark 2) repaired by experts (more expert than me), that I gave up and enrolled in a State Vocational School for 12 weeks and attended Automotive Air Conditioning School. I graduated and with what I had learned and the Factory Shop Manual, I rebuilt my system myself. Knock on wood it is still like a freezer in there, 10 years after!Once you get the Delanair system up to standard, you will realize what a fantastic climate system it is.

The best gas is R12 whetheryou can afford it or not,just bite the bullet. Forget about R134a, it is as bad as Haynes Manuals. Or try alternatives such as Freeze12. (do your own research).
I don't understand why people fall for R134a, it's garbage. R134a does not cool at idling, and when the car is moving, it'sdissapointing cooling at best. The Delanaire system was designed for R12. Stick with the best.

Fortunately, the Series 3 XJ-6 Delanair Mark 2 system 1980½-1987 USA market, (lots of descriptions aren't there?) is an "Expansion Valve system", as opposed to an "Orifice Tube system" as in modern cars and which are nothing but caca.The Expansion Valve is located in the center of the firewall, right behind the cylinder head, connecting to the "matrix" or Core inside the cabin. It is usually covered with a tar-like gooey stuff over it (the stuff is sold at NAPA) to protect it from the engine temperature. This Expansion Valve is the one component that you always replace in any rebuild of the XJ-6 Delanair Mark 2 system. They do get clogged.

You need two wrenches to remove it, otherwise you could break the piping and then you're in serious trouble. I mean serious trouble. So don't break it. Use lots of lubricant before attempting to undo the large nuts. The Expansion Valve is American-made, available at most auto parts. Cheap. eBay.

Then you need a new Dryer, located in front of the radiator, sideways along the top.Available at Walgreen's, and most other supermarkets. You don't need a prescription. CarQuest has them. Motorcars Ltd. has them. The US Post Office has them. The Russians have them. Mother Teresa has them. I have them. You just have to shop around.

The compressor is a General Motors Harrison A6. Bullet Proof, $149.97 + tax. at autoparts everywhere. El Shoppo Aroundo.

Those three components are paramount in any rebuild. About $250.00 or less worth of parts.

But you need to find out what gas you have in there before you open up the system to atmosphere, it's illegal to release any refrigerant gas to atmosphere, and besides: refrigerant gas can make you blindin an instant.

So you go toyour local friendlyA/C shop and ask them to "recover" whatever gas is in there, and to tell you what it is.(they now have recovery machines and gas analyzers).

Tell them you want Virgin R12 and nothing less when you bring it back for recharging. It they don't do R12, go somewhere else. Many a/c shops still have R12 tanks and they will continue to have it.Brazil and Mexico are still making R12.Don't settle for any less.

The rest of the components, like the Condenser, you can just FLUSH, no need to replace it.

Inside the cabin, there's lots of components that rarely go bad, they will last 30-40 years without any trouble, except the Amplifier. The amplifier is the one component that you MIGHT (repeat: might) have to replace. They are available from many sources. There are modern versions redesigned for longer service.

Well I hope that helps. Take a look at the Expansion Valve below.

Jose

[IMG]local://upfiles/1235/0097DD7DFCB34221B346A4CBB1D7395D.jpg[/IMG]

RE: A/C series III
 

Jose,

You're right about some loss of efficiency with the R134, but I haven't found it to be as pronounced a difference as you indicate. Most owners wouldn't want to bear the incredible cost of R12...and if a shop recharged a system with it, only to have it escape from a new leak source on a long dormant system...somebody won't be chillin'.

RE: A/C series III
 

Jose - JagtechOhio - you guys rock! Jose, you don't have to sell me on the Hayne's manual sucking. It's been next to useless. the JTIS for my 98 xjr is 1000 times better already. Where do I get a "factory shop manual cd"?

This project sounds like a bear - not a weekend project. I may dive in...eventually. It sounds like the first step is a gas recovery.

RE: A/C series III
 

JagtechOhio: I have tried some XJ-6 both in Tennessee and Florida with R134a. When comparing the level of "cold" in a R134a car to my system which is charged with R12, there is just no comparison, R12 gets really "cold", R134a gets "cool". I suppose most people can live with R134a, but not me. I like it freezing cold, especially with the kind of hot summers we are having. An a/c shop can test a dormant system by charging with compressed air BEFORE wasting any refrigerant, I learned that trick at a/c school. And if a system is going to be more prone to leaks, it will be with R134a, which creates higher pressures than R12.

Skan,get the Factory Shop & Service Manual CD at: http://www.lbcarco.com If you can get the Technician's Manual, even better, they are available, very expensive, about $300.00 for a new set, but for around $25. you get all you need in the CD.

Jose

RE: A/C series III
 

Jose,

Thank you very much for the lesson! I'm really Impressed.

RE: A/C series III
 

JagtechOhio, you are welcome. Another thing to consider when changing to R134a from R12:

The HOSES will need to be replaced because R134a SEEPS/BLEEDS/SWEATS through the R12 hoses, talk about leaking!

So the bottom line being money, by the time you have replaced all the O-rings, hoses, Expansion Valve, Dryer, Compressor, and possibly the Condenser as you said, you could haverefilled with R12 and only replaced the needed parts.

Alternatives to R12: There are many other EPA-approved alternative refrigerant gases. You don't have to use R12 or R134a only. There is Freeze12, which is a mix of R134a and R22 (R22 is the refrigerant used in residential a/c systems and commercial freezers). And there are many other non-flammable refrigerants.But for each alternative refrigerant, you have to buy a set of fittings, gauges, and labels designed for the particular gas.

Coolers in supermarkets, gas station mini-markets and suchstarted using R134 because it is so cheap.Have you noticed that the coolersare notas cold as in the past? People complained, especially in supermarkets. They went back to R22.

[sm=nxsmile.gif]

Jose

RE: A/C series III
 

Wow, that information even supercedes the Jaguarfactory R134 retrofit instructions!

:)Can you teach my little guy how to blow smoke out of his face too?

RE: A/C series III
 

do you mean the Jaguar retrofit instructions do not say to use Barrier Hoses when using R134a?

Also, I would not teach your little one any nasty habits.

RE: A/C series III
 

Jose, you are correct about the hoses. But he's right, too. The Jaguar kit has o-rings and a drier bottle. That's it.

Anyone know a good air con retrofit kit for the xj6 series III ...

here's some diag info:

http://cid-562a51a1e467595c.office.l...20Delanair.pdf

nice...thanks very much bbarcher...

Have you tried buying an aftermarket recharging kit for about $60.00 and recharging the system. They usually come with a can of sealer, 2 cans of freon and a set of gauges. It might be that you have a slight leak ant the freon is low. As someone stated earlier the compressor will not come on when the freon is low. The recharge kit is simple to use and might cure the problem for the season. I have used it once in my 1986 XJ6 with great success. I have used it in my 1996 Chrysler every couple of years for the past 10 years. I know it's not a complete solution but you could spend a lot trying to solve this problem.
Bill

Jaguar #44 Delanair Mk 3 Air cond. fault diagnostic manual
 

Good link with excellent info on the Delanaire Mk3. Do you have a copy of "Jaguar #44 Delanair Mk 3 Air cond. fault diagnostic manual" by any chance?

Cheers
Clive

No, sorry.