I'm going to be putting AC in my 1967 420 this winter but wanted to see if anyone has any been there/done that advice.

I looked at the Classic Auto Air kit and read the instructions. If I am reading it right it sounds like the evap box is in the engine compartment (where the battery sits today) and I don't know if I want to do that.

I also looked at the RetroAir kit but there is not a lot of information available about how it installs. I emailed them for more info but haven't heard anything back in a week.

Moss has one but I am guessing it's a re-packaged version of one of the two above.

I enjoy doing AC work and I have thought about a stand-alone under-dash AC unit, maybe something like this. I can make my own compressor mount and crimp my own hoses so the lack of it being a kit appeals to me.

Any thoughts or suggestions from those that have been down this path? Anything you wished you had known before you started?

 

Classic auto air bought out retro air several years back (5/6 yrs ago). To install their a/c system you have to cut up the dash panel (firewall) and, as you mentioned move the battery to the trunk. I believe you are correct that the Moss system is classic auto air system. I wouldn’t want to cut up a dash on such a nice car. Will cutting holes in the dash affect how the bottom of the windshield is supported? What will happen to the dash in a crash? Will the holes effect NVH?

I have seen several under-dash systems installed in 420, mainly in Europe. They either cut up the console and relocate the radio (in my opinion it looks like ****). Or put it on the passenger’s side, which makes it a knee-knocker getting in and out. It can also bust up your passenger’s knee in a crash.

if I was you I would get ahold of George Camp of the
Coventry Foundation and JCNA. He is very knowledgeable about Jaguar’s older A/C systems and how well they work.

p.s. I designed A/C system for one of the big 3 for over 30 yrs and was a technical expert for over 10 years before retiring. I’m not crazy about either design.

cheers,
Bob S
Jag of Michigan

 

I also refuse to move the battery to the trunk, that is why I never purchased the Retroair a/c system.
Do not expect a reply from them either, something happened with its owner Rock Browning and noone is minding the store.

What I would like to do is use the existing Heater Box and modify it so it has both heat and a/c coils.
Yes I know it could never be very efficient but it would be better than no a/c at all. No?

I have all the parts needed to do an a/c system including a spare Heater Box to sacrifice for the project, what I cannot do is modify the box with another coil and hose connections.

A firm called Wilkinson in UK did it using the heater box.

 

Modern efficient units can be fitted without cutting up anything or moving the battery. There is space on the passenger side shelf. This was dealer installed in Winnipeg in 1966. Old York thumper compressor ~ Today they would fit a compact swash plate compressor that runs all the time & only pumps when you apply an angle to the swash plate ~ no more clutching in & out. No battery moves etc. Today they are even more compact and work well. Go to a good shop & explain your needs. With a modern swash plate compressor I doubt the slight inner wheel arch depression would even be required. Stipulate zero modification & butchering. A Mercedes Evaporator & fan fit behind the console & will freeze your cobblers off.

See from post 73 ~ all questions answered by Prof. Gregory. (sov211)

https://www.jaguarforums.com/forum/m...-246106/page4/

 

@Bob_S - thanks for the information. I also worried about NVH from the holes in the firewall but to me the bigger issue is the evap core being in the hot engine compartment and having to battle that + cooling the car. It just seems - inelegant.

@Jose - Thanks for letting me know no one is watching the store! My concern with putting a evap core in a heater box is moisture control, and the above point about the evaporator being in the engine compartment and trying to insulate it from the heat that's already there. The other concern is that you really want the cooled air blowing on you, and at least in my 420 there aren't any face-level vents. The footwell vents only blow air as high as my crotch - which would be nice but not good enough.

@Glyn M Ruck The passenger footwell unit is a step in the right direction. It's inside the car, but I think it would need some ducting to the driver's side. Also, thank you for the link. There's some great reading there.

I think I'm going to pull the lower dash shelf and the center console and see what I have to work with as far as space goes. Last winter I replaced the Delenair Mk III system in my XJS with a Vintage Air box and I'm hoping to not be so involved this time around. I think my car had air at some point so I also need to explore the trunk and rear package shelf and see what's going on.

Thank you for all the ideas!

 

Thorsen,
then your other option is to install the factory system which placed the evaporator in the trunk behind the rear seat wall. A giant evaporator to say the least, and giant hoses traveling under the car to reach the condenser and conpressor..

BUT: it is not a "in your face" system. Air is blown from the back of the car through ducting on each side of the interior above the doors. And cutting holes in the rear parcel shelf and floor is inevitable.

My S type and your 420 were not anticipated with a/c systems as they were with Seat Belts.

A friend in Tennessee did the Heater box modification in a MK-2. This was at a time when R12 refrigerant was available to consumers. I got to drive the car with a/c running and it was a pleasure. He cut two holes on the wood dash for vents and added two more on each side of the center console. Plenty air volume and force with a different 4-speed blower. With windows closed the car was very cozy inside. He insulated the box with modern stuff.

I don't know about the humidity, seems to me he had no issue with it.

 

To see what's possible and as a starting point for a DIY air con, I bought an old XJ Delanair tin box. With the car interior stripped out, the box just about fits in the space between the instrument panel, bulkhead and transmission tunnel of my Mk2. Since the Delanair is hardly the most compact type, it shouldn't be difficult to make an integrated heater and air con that goes in there, isn't too conspicuous and eliminates the awful heater box from the engine compartment. Almost all modern cars down to the smallest have under dash air con so an effective compact arrangement must be possible.

It's a lot of effort to install air con and not have the benefit of face level vents. I'd try to arrange them at the outer ends of the dash.

 

Placing a duct on the drivers side of the car is simple. Aircons can be built up today from all the basic components required. Here is an example of 4 ducts fitted to an S Type. Just requires a little imagination. Space is no longer the issue. They will blow in your face if required.

 

Glyn, Do you know where the evaporator is in that car? I'm assuming in the engine bay, where the battery would usually be?

 

It's in the airbox modified with the heater matrix & similar to the Merc unit below.

 

You don't need an evapourator that takes up half the trunk when a modern 8" X 6" evaporator will do a better job.





Mercedes W 203 Schematic. ~ all hidden behind the console. Ultra compact & will comfortably go down to freezing if not adjusted correctly. This is a 2003 C Class. Sniffer fan & sensor in the overhead console measures in-car temperature. My new car even has a sun sensor and blows colder on the sunny side of the car.



1) Pleated paper & Charcoal filters
2) Fan
3) Evapourator
4) Heater matrix ~ with condensate drain just below it.
5) M2 numbers ~ all flaps are driven by stepper motors.

 

Yes Glyn, the OEM jaguar system was large, uncle! A/c components have come a long way since the 60’s. But so has engines and almost everything else. But that Mercedes’ system isn’t small either. The center stack area of the IP is considered the most sought after real estate in the vehicle. What are the for-aft, side to side and height of that entire system. That evap core is probably 40-50 mm thick, 200-250 mm tall and 200+ mm wide. I’m betting that it’s designed by Denso and took several years to package and develop it by a team of people. It’s custom fitted to Mercedes dash, center stack height and x-car beam.
Cheers,
Bob_S

 

It uses a Nippon Denso swash plate compressor but is ultra compact. It does not enjoy the real estate of an S Class. Anyway I agree a lot of thought went into it & we have come a long way. I don't know how much Denso input there was. Merc is hardly half asleep themselves. It leaves space for the genuine CD driven Sat Nav & Telematics unit that is not exactly small. We are talking an ultra compact retrofit here which is easily possible in a S Type without butchering the car. Prof. Gregory's car shows what was possible in 1966

 

I have been looking to fit a climate control system to the front of my Daimler DS420 and that's not easy either. An evap itself is reasonably easy, but adding in a heater core, blend door and blower with effective ducting isn't. I've done lots of looking and figured that there is no way to fit anything effective without metalwork to the firewall.

The S is different, but still equally tight. The shallow firewall to wood fascia depth is a major challenge.

 

JB ~ You could fit the evapourator & heater matrix into the heaterbox with mods to the box. That is what this guy in Dallas had done & it looked neat & did not stand out like a sore thumb. Battery was not moved. I don't know the Daimler well enough to comment. As you know I'm an S Type man. I'm now sorry I did not take more notice of his heaterbox mods. See my comments to Bob above. You know Prof. Gregory's car. All it has is a dimple in the inner LH fender to accommodate the York thumper pulley/clutch. And that was 1966.

 

.

 

.

I know your car had A/C because I bought the system from It. Tim didn’t think he needed A/C in the Chicago area, but my kids told me it was 95f (35c) + high humidity there Saturday .

cheers,
Bob_S

 

@Glyn M Ruck I think my car had air at some point so I also need to explore the trunk and rear package shelf and see what's going on.

I did not pass this comment.

 

The Daimler is a Mark 10 that's been stretched, so it's a typical 60's Jaguar - no space behind the dash. The engine bay components is easy, as my car came with dual front/rear AC, but the front was the same system as Gregory's Mark 2. That means my passengers knees freeze and the driver gets no cold air. The difficulty is similar to the S Type, in that there is very little space to mount and duct anything behind the dash.

I have given occasional though to putting AC in my S Type, but there isn't an obvious solution that will perform well without major effort and/or fabrication. I had thought about mounting an evaporator in the heater box, but a blend door would be difficult to engineer, and have a blower with sufficient airflow to actually make the effort worthwhile. The heater box is pretty small too and evaps need to be bigger than heater cores.

 

I had a quick look: 60mm thick, 303mm wide and 200mm tall.