My 53 plymouth is stock and runs good, but i would like to add A/C with out destroying the look of the original engine bay. I dont want to lift the hood and have this compressor sitting on top of the engine block, an alternator, and a/c hoses destroying the look of the original car. I think i can install the compressor down low and under the generator, so it would be hidden from sight. I am planning to use a trunk mounted vintage air system so the lines would be ran under the car and out of sight. the orginal dash, defrost, heaters, and radio would be untouched. Here is where i run into problems. My car is 6 volt postive ground the A/C comressor will not run off of this. I am wondering if i could install a seperate 12 volt battery and run the a/c on its own elctrical curcit. There would be no way to recharge the battery other than removing it from the car and putting it on a charger. How quickly would a a/c alone drain a 12 volt battery? Will i have problems withe the 12vlt /6vlt system running at the same? is this a fire hazzard? is the compressor grounded through the case, or do they typically have a seperate wired ground? How big of what type of battery do i need? (marine deep cycle?) any other tips or hints i should know? has anoyne else done this?
Seems like you are doing things the hard way. Two batteries? A separate charging system? Do it once, do it right, and talk to the people on the P15-D24 forum who are experts in this sort of car, and some people have done things like this. Yes, you would need to completely isolate the 12V stuff. Suggest converting the car to 12v and hiding the compressor lower left, running the compressor lines back toward the steering wheel and then along the firewall to the A/C unit. Your old cloth wire is a fire hazard, wiggle some and watch the insulation fall off.
i have already rewired the entire car, so that is not a problem. i dont know exactly why but i am against converting the car to 12 volts. everything works good, starts right up, lights are "bright", the tube radio works. why should i change it what does it offer me, except step down units to break at the radio and all gages and a ugly ass altenator in the enging compartment....
Not completely isolate. The 6V positive ground and the 12V negative ground can be a common "bus". As far as how long the battery would last running the blower fan and compressor clutch before needing to be recharged, I really doubt you'd get much more than an hour out of it, but of course that would depend on how big of a battery you use. There is a lot of risk of damage to the compressor clutch by trying to run it on a weak battery. And it's always nice to have an A/C blower fan that runs at it's peak as well. And don't forget that you also have to install a condenser in front of your radiator, which likely means having to beef up your cooling system. Now you're talking the possibility of an electric fan by the radiator, blah, blah, blah...... I'd highly recommend a change to a 12-volt system, but if you insist on a separate 12 volt system for the A/C, you could probably hide one of those small Denso alternators pretty well, and you wouldn't need a large 12-volt battery at all, since it is not used for starting your car. You could probably get by with some type of motorcycle battery.
figure about 75 amp hours for a typical group 24 battery, if the blower draws 15 amps and the clutch 5 amps then you'll get a couple hours out of it, or so. As a philosophical thing....I figure if you're gonna wimp out and put air on the car, you might as well wimp out and make the car 12v too.
I would think your biggest issue is going to be that the compressor is going to be grounded through the compressor casing, which if that's the case. Having a 6 volt positve ground and running 12 volts to the compressor is going to make things all kinds of messy. I would personally bite the bullet and switch the system over to 12 volts. You can always get voltage reducers for your dash and radio to keep the same look and sound.
Go to 12V if you gotta have air.It'll be cheaper and easyer.Running two electrical systems would be a mess.
There are two possible approaches you might consider: 1) Use another 6V battery and hide it somewhere. Then connect the two in series with the generator being a 12V type. You can reverse the grounding if need be, but by doing it this way you will still have the 6V battery under the hood and everyone but you will think it still is a 6V system. 2) Do the hidden 12v battery thing and as suggested use the common ground method with the negative post being ground and the positive post being for the A/C components. Then use a 6V pos gnd to 12V neg gnd upverter to do the charging. If you could get your 6V blower motor to be used for the A/C you will only have the 5 ampere A/C clutch for the 12v battery and upverter to have to deal with. Need more information PM me.
There are billions of electronic things in the world that have "mixed" polarity devices in them, with a common ground reference. Any "mess" would simply be due to the duplicated items and wiring that you'd have with two completely independent electrical systems in the car. However, the electrons involved in this kind of a setup with a common ground bus (ie. one system negative ground and the other positive) are not concerned at all, and will get along with each other quite nicely.
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