Install tips for Classic Air A/C Underhood kit for a 1970

[CarZombie 25]

In July I received the Classic Auto Air under hood kit for my 1970 Mustang. I had two problems with it. Problem one, the instructions are a joke. They are worthless. The second problem was the original condenser and a replacement condenser did not fit. On the third try, Classic sent me a different style condenser which fit, after an adjustment. Since the instructions are so poor, I thought I would post a few pointers about the kit, which might help some poor Mustanger somewhere, sometime. This is not an all inclusive how to install.

1. First tip, have a basic knowledge of how the AC works and the liquid and gas flow. A generic schematic is very helpful.

2. If you have old refrigerant in the system, get the system evacuated prior to disassembly. I personally think the Ozone is overrated, but draining the system in your garage is going to be messy.

3. Once you have the kit, check the fit of the condenser. According to Ron Mineo, my salesman at Classic, the mounting brackets on the condenser should line up with the factory holes and the lines from the condenser should fit in the stock AC line opening. If your condenser does not fit the stock mounting holes or there are other problems, stop and call or e-mail Classic.

4. My hoses came packed in Styrofoam peanuts. The hoses were capped, but one of the caps had come off. I strongly recommend you blow through all of the hoses to ensure there are no little pieces of Styrofoam in them.

5. Buy at least one can of AC flush. You are looking for a pressurized can with a nozzle. I could not find it on the NAPA web site, but my NAPA store had it for less than 20 bucks. The evaporator has old refrigerant and oil in it. This needs to be flushed out prior to installation of the new lines. Once you have all the old lines off, put a catch pan under the outlet of the evaporator, put the nozzle into/against the inlet of the evaporator and trigger the flush. After the can is empty, you will need compressed air to finish the flush. I used my air compressor. I did not like doing that, because of the water vapor in the air stream, but the system must be vacuumed prior to refilling anyway.

6. The Classic kit comes with a high/low pressure switch. Since there are no instructions, you might not be able to figure out where it should be placed in the system. This link, http://i1202.photobucket.com/albums/bb361/CarZombie1/Presureswitch.jpg shows you the switch is attached to the dryer and the hose coming off the evaporator. Notice the two white wires coming off the switch. The kit comes with a female connector and a male connector that you will attach to the two wires. The female connector mates with the male connector coming off the compressor. The male connector mates with the female stock connector coming out of the dash/firewall. IMPORTANT, the male connector is an odd size. Don’t lose it or screw it up. I spend half a day trying to find one. Off the shelf connectors are either too small or too big. I soldered my wire to this connector, after trying several times to get a good crush fit. Here is a link showing these connectors: http://i1202.photobucket.com/albums/bb361/CarZombie1/Cutoffswitchwires.jpg

8. Regarding the dryer, it comes from Classic separate from the condenser. It is pressurized, but you don’t have to wait to the last second to attach it to the condenser, according to Classic. Check and make sure the top fitting, the one the pressure switch mounts to, is 90 degrees. My first dryer was off and it caused problems. I know the picture makes it look as if the fitting is off, but it is not, the dryer is canted back to allow room for the pressure switch.

9. The mount for the Sanden compressor has a strap which straddles the side of the old compressor mount. See this link, http://i1202.photobucket.com/albums/bb361/CarZombie1/Closeupofgap.jpg and this link, http://i1202.photobucket.com/albums/bb361/CarZombie1/BracketOverview.jpg These pictures were taken prior to tightening the bolts. The gap shown in the pictures freaked me out, as I thought the aftermarket strap was going to bend and look terrible. I called Ron Mineo, and he said they got that a lot, but if you leave the two end bolts lose and then tighten the top bolt and then the end bolts, it would draw down to the stock mount. It did, as shown in this link, http://i1202.photobucket.com/albums/bb361/CarZombie1/Bracketgapclosed.jpg While you are looking at these photos, note the space goes to the rear of the bracket.

10. The nuts shown in this link, http://i1202.photobucket.com/albums/bb361/CarZombie1/Mount.jpg are not from the kit, I just feel more comfortable using that style of nut. I aligned everything up with the bolts lose and used a straight edge to make sure each pulley was aligned with the compressor pulley and the adaptor plate was square on the stock mount. Once I had everything lined up, I tightened the bolts holding the adaptor plate to the stock mount first, then the straddle bracket.

I was very disappointed about two of the condensers not fitting, but Ron Mineo was super about taking care of those problems and he was very responsive to my questions. Classic really needs to provide a detailed set of instructions with the kit. Would I recommend them? Yes, just because of how responsive they were in dealing with me.

[LiLMike 42]

Great information CarZombie! Thanks for the writeup. I don't think I'll have quite the trouble you had since my stock system has been removed by the PO. I'll be using their "Perfect Fit" kit. I have looked over their instructions and they are not too bad from what I can see. I'll have lees problems with your hepl too...Again, Thanks.

[stangracr 10]

How much freon did it take to get the system full. I just installed this kit also.

 

 

 

ed

[CarZombie 25]

Short answer, I don't know. I had the system evacuated and filled by a AC shop. Classic sends a conversion sheet, but I could not make heads or tales out of it. I guess my shop did not have much luck either, because when I drove it home the compressor was laboring and cutting in and out. Returned it to the shop, and they had to take some of the freon out. On the plus side, I know my high/low pressure switch works.

Edited September 14, 2011 by CarZombie
Grammer

[stangracr 10]

I was just wondering. I charged mine at my work. I have about 30 oz in mine right now. Seems fine and the pressures looked pretty good. I just wish I had an exact amount.

 

ed