Guidance: installing A/C into 280Z

[MM569457]

Good afternoon!

 

since getting the Z road worthy this past spring, I’ve debated installing A/C in the car since, well, because Texas. My father removed all the components from under the hood, and the remaining original HVAC components are located under the dash. He didn’t take global warming into account in the 90s. I’m looking through the FSM right now, but I’m debating weather to replace the under hood components from Motorsport auto or go with vintage air.

 

1. What considerations do I need to go over, and what steps should I follow through?

 

2. what advantages does Vintage Air have over replacing the stock components. 
 

thanks in advance!

[Patcon]

I am unsure , but I think the Vintage air is thought to flow more air and be more efficient

I don't know enough about new refrigerants in old coils to advise on that though

[SteveJ]

First do your research on auto AC basics. I'm betting there are a lot of YouTube videos and websites that can give you the basic knowledge of components and their function in the system. 

As for re-using old components, the drier is DONE. I wouldn't trust it even if it was sealed. Since 280Z driers are unobtanium, that does shift you toward aftermarket. Another factor that should push you toward aftermarket is the fact that expansion valves are also made of unobtanium. Without a good expansion valve, your AC system is a lead weight in your car. The design of the stock system doesn't facilitate using a different expansion valve.

Just my opinion.

[cgsheen1]

18 hours ago, SteveJ said:

... is the fact that expansion valves are also made of unobtanium. ... The design of the stock system doesn't facilitate using a different expansion valve.

Just my opinion.

Not opinion - that's fact.

And while I prefer keeping the A/C in these things as stock as I can, there are very few of us that can deal with all of the oddities.

I've been toying with the idea of building a more stock-like A/C system for both Lates (74-78) and Earlies (240Z (the Japanese S30 had A/C as an option)) using new and more easily obtainable parts. Maybe someday... 

Edited August 18, 2023 by cgsheen1

[Patcon]

That would be really neat if you could come up with a kit that piggy backs onto the car the way the original factory system would have

[Dave WM]

if you can source a new OE fitment evaporator and it the rest of the stuff is in good shape (switches, solinoids, idle up, vacuum actuators) that is if the only thing that is NOT working is the evap getting cold, then trying to go full stock would be less work. Pretty sure new evaps with current style TVX are out there, just take some looking. They fit into the evap housing, so as long as the air handling part is functional you are almost there. The under the hood stuff is easy, you can source a new compressor with an aftermarket style mount, this will take some fabrication, or if you can source a swp123 type compressor, then you can use that with the OE compressor mount. Hard lines should be ok, new drier of course, but as I said the under the hood stuff is pretty generic. Its all in the air handling and under the dash that makes it hard. 

IF you decide to go with all new non OE air handling then be prepared for some serious fabrication. I have not seen too many in depth  documented installation of the under the dash stuff. You have control layout, vents, wiring, heating to work out. 

The biggest down side I have on the non OE is the lack of a proper outside vent hook up from the cowl vent. All the aftermarket air handlers seem to have you just seal that up and just recirc the air. I suppose its not that big of a deal, but I like the option on cool days to run fresh air thru the dash vents. 

[Jeff G 78]

2 hours ago, Dave WM said:

if you can source a new OE fitment evaporator and it the rest of the stuff is in good shape (switches, solinoids, idle up, vacuum actuators) that is if the only thing that is NOT working is the evap getting cold, then trying to go full stock would be less work. Pretty sure new evaps with current style TVX are out there, just take some looking. They fit into the evap housing, so as long as the air handling part is functional you are almost there. The under the hood stuff is easy, you can source a new compressor with an aftermarket style mount, this will take some fabrication, or if you can source a swp123 type compressor, then you can use that with the OE compressor mount. Hard lines should be ok, new drier of course, but as I said the under the hood stuff is pretty generic. Its all in the air handling and under the dash that makes it hard. 

IF you decide to go with all new non OE air handling then be prepared for some serious fabrication. I have not seen too many in depth  documented installation of the under the dash stuff. You have control layout, vents, wiring, heating to work out. 

The biggest down side I have on the non OE is the lack of a proper outside vent hook up from the cowl vent. All the aftermarket air handlers seem to have you just seal that up and just recirc the air. I suppose its not that big of a deal, but I like the option on cool days to run fresh air thru the dash vents. 

Thanks Dave.  I'n in exactly the same situation as the OP.  I bought my '78 280Z 33 years ago not running.  I removed the A/C compressor when I bought it, so I have no idea if it worked or not at the time.  I have all the parts, but without knowing the condition of any of the components, is it worth keeping?  I now live in Phoenix, so a feature that added weight and wasn't all that important back east, is now a must-have.  I'd like to at least keep the HVAC unit and maybe do a blower upgrade, but I just don't know.  I think the OP has exactly the same dilema.

[Dave WM]

I would take the time to check out the air handler. You want to make sure the heater core is not leaking, and all the actuators are working as they should. there are some that are just cable activated some that are vacuum line operated. I would start by just trying it out and see what happens, dont worry about getting cold air just check the air flows. IF all you get is frost mode (air thru top of dash) then I am pretty sure you have lost vacuum (defrost IIRC is the default mode). If that happens check you vacuum source 1st. that is the plastic bottle near the carbon cansister. You may find broken or just disconnected vacuum lines, as they tend to become loose over time. There is also a one way valve that can malfunction. So 1st off is to make sure you are getting vacuum to the system, there is a vacuum line that runs from the intake, to the one way valve then to the bottle. From there IIRC there are some solinoids that are connected (back half of engine bay right side)and a line that goes with an electrical harness thru the firewall. Inside is a vacuum multiposistion switch that directs the vacuum to various places based on the position of the selector lever. there are two large vacuum power actuators. One of which is a two posistion actuator (goes from zero to 1/2 to full, two supply nipples for vacuum). I suspect the lines in the cabin will be ok as they are protected from heat. 

Anyway if you can get the heat working and if you can redirect air using the levers, then I would make an effort to try to just use that, it works pretty well and will get you up and running with just the under the hood stuff to tackle. 

the evap "may" be ok I have some videos out there with me testing the TVX, but if it was me I would check to see if the compressor  is not locked up, and see if it can pull a vacuum and hold it. If so replace the drier (you may need to bend the hard lines depending on if it has the unicore drier), pull a vacuum and charge it with some R12. Its up to you to find someone that can do the R12..

If it does not hold vacuum try a pressure test, I used nitrogen at about 80 psi, see if it hold pressure, if not spray some soapy water all over the hoses and connection under the hood, look for bubble, fix that and try again. My old swp makes a racket but has working after 8 years with no refills so you may get lucky like I did. My only leak was the condenser, I found a NOS one and bee good since.

Edited August 19, 2023 by Dave WM

[MM569457]

Ok, suffice to say my best bet is to replace the evaporator of going with the Motorsport set up, or go with vintage air, bearing in mind additional fabrication will be needed (fresh air inlet plugging, etc.)

 

 

[Yarb]

Not sure how you would incorporate fresh air into a Vintage system. I assume you could contact them and go from there. From what I’ve read here most folks were asking how to cap it off the intake door after the install.

[Patcon]

Bear in mind R-12 has gotten very expensive lately and might change your monetary calculations. Check cost and availability before choosing a direction

[MM569457]

I found a possible solution. Autoacsolutions.com. A but priced, but it appears to have everything I would need.

https://autoacsolutions.com/products/ac-kits/add-on-air-conditioning-heat-and-defrost-air-kit-with-integrated-controls-for-75-76-77-78-280z/
 

I’ll need to see if the dial switch can be switched for a 280Z slide lever.