atcfixer

iTrader: (1)

I know there's a ton of these trucks with no ac (mainly looking at 84-89 era). The ac amps are pretty expensive and hard to find. Wonder if anyone would be interested in a new sub harness that would wire a newer AC amp up to the AC harness (the one with the fuse box and relay)? I'm thinking like late 90's era 4runner or mid 2000's Solara since they are cheap currently (maybe make multiable adapters so just one model doesn't shoot up in value). I've been studying the AC system, and the biggest loss from the newer AC amps is there's no low rpm "protection", aka if the ac kicks on, and the idle kick up doesn't work, it could stall the engine. I'm not sure if the 84-89 trucks would cut ac off for high rpm or not, but if they do that feature would be lost too. Besides that, I should be able to make the adapter harness to make it work.

Of course I'll need someone to test the setup too. Clearly this is only a small part of the ac system. Just wanted to gauge if there's any interest vs just sticking with the OEM ac amp and getting the related wiring. I'm planning to make the stock sub harnesses. The sub harness with the fuse and relay will have to wait till much later since there's several new connectors I don't have stocked.

Anyway, feedback or more ideas always welcome. One down side I see from this setup is the newer ac amps won't fit in the stock location, so the Solara one would be better since it's made in a plastic box already (not just a circuit board)

swampedout

ive got a 1980 pickup Id love to add AC on but thats a different horse probably

atcfixer

iTrader: (1)

I'd have to look up the data, I have a 1979 wire diagram book. I haven't put it on my computer yet to make it easier to look at and screen shot though.

swampedout

Its a long term project for me, Id have to source or fab a compressor mount.

atcfixer

iTrader: (1)

Worst case, you should be able to wire in the 84-88 style ac system, just have to find what all it ties into for the rest of the vehicle. Pretty sure it's mainly the power, ac switch, etc.

Pulled up the 79 diagram and took a quick peek over it, it doesn't use an AC amp, it has a relay control switch and I assume the switch tied to the thermo side of things is what tells it to turn on/off the ac pump and such.

swampedout

Im hoping to use a 94+ system so I can have r134a. Im not against an older system but for servicing it and finding parts, its more headache.

atcfixer

iTrader: (1)

R134a can be installed in the old R12 systems, it works on a bit higher pressure if I remember right, but it's within the margins of the R12 system. The older 79 one looks to switch the AC based on pressure, so converting one from that era to R134a might not cool as much, the atleast 86+ style used the temp to control it, so that would automatically push the pressure in the ideal range. 89-95 should be more common though. I haven't really looked into their ac amp circuits, but should be real similar since the 97 4runner I looked at wasn't much different.

swampedout

My understanding is R12 gets a lot colder, so Id rather skip a retrofit and just go straight to a system meant for r134. Its been hard finding those old parts anyways. Even the Ac in my 84 F250, hard to find parts.

My idea was something new and universal-ish. I can run ducts and do all that custom. But the big components would be nice to plug n play and buy a cheap replacement online in the future instead of digging around for the one website that still sells the older stuff.

atcfixer

iTrader: (1)

Yea, I might be able to do something like that down the road. Like using a newer vehicle's ac amp and provding the basic working for a "universal" kit. Not sure how universal it can be across brands, but toyota's design doesn't seem to change too much.

R12 gets cold faster, but that's because it works at a lower pressure (it gets to the pressure faster). Besides that the system works extremely close to the same for both.

To change the view a little, think of water, when it evaporates, it cools, grab rubbing alcohol, it also evaporates, but does it faster so you feel the coolness quicker. That's kinda like R134a vs R12.

swampedout

The truck is a major project, Im building a new dash for it anyway so I can fit controls and wiring however is needed

swampedout

Makes sense. Im a residential Hvac installer by day so I know some basics but not too big on the theory behind all of it.

Big-o

Hey Atcfixer. Are you still making these ac adapter pigtails. The Ebay link didn't turn up anything.

atcfixer

iTrader: (1)

I haven't really had any interest in them and I haven't gotten the parts for testing the setups so kind of dead in the water project. I wanted to reproduce the boards too, I've had like 3 people with burnt up boards telling me they'd ship it to me for free, give them the address, but never receive it.

I've changed focus on my business a bit and I mostly make demo derby harnesses now which has kept me really busy. I guess a harness for competition is a different buyer view point than a daily driver/show truck. The 90+ stuff has much better documentation on the wiring side of things, so that's been a big help too on the demo derby side of things.

I'm not sure what ebay link you're talking about, I looked over the thread and don't see one, but it's also several years old of a thread now so most ebay links would be dead anyway.