A/c in motor swap
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A/c in motor swap I am in the process of putting a 2003 5.3 (pulled out of a Tahoe) into a 93 Ford Ranger. I am trying to save as much money as I possibly can, so I am trying to use the wiring harness as well. I pulled the entire harness from the Tahoe. Ok so here’s the thing. I am trying to clean up the harness as much as I possibly can, getting rid of wires that don’t necessarily need to be there. I am using LT1Swap for guidance, and I am trying to figure out my best way to run a/c. For the sake of money purposes, I am trying to keep the stock compressor on the 5.3. I heard that it’s better to run it standalone without being tied into the harness. How would I go about wiring it like that? Would that really be best? Or just let the computer control the a/c motor? How would I tie my dash controls into the ac to control it then? (P.S. sorry so many questions... yes I know easier to just take to a shop, but like I’ve said... saving money. Plus I know I am fully capable of doing it myself.)
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Joined: Dec 2017
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From: Bossier City, Louisiana
I have a similar swap in a 70 El Camino and I'm NOT running computer control of air conditioning via PCM. To turn my compressor on, I ran the turn on wire to the compressor and tied that wire into a separate electric fan controller - "Four Seasons pn 35879" for about 35 bucks. My "Classic Air Conditioning" system is still fully protected with low pressure and high pressure safety switches. The Four Seasons fan controller kit overrides the radiator fan temperature sensor via its green wire the instant the compressor kicks in. Compressor on = one fan instantly turned on. You must do it this way to keep compressor head pressures in the proper range. You can't wait for a radiator temperature sensor do this for you.
My Cold Case radiator has two fans and I have two of these Four Seasons fan controller kits. One for each fan. Each fan has its own power, ground, relay, adjustable temperature control and temperature sensor for complete safety and cooling reliability.
Rick
My Cold Case radiator has two fans and I have two of these Four Seasons fan controller kits. One for each fan. Each fan has its own power, ground, relay, adjustable temperature control and temperature sensor for complete safety and cooling reliability.
Rick
Thread Starter
Registered User
Joined: Oct 2019
Posts: 4
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I have a similar swap in a 70 El Camino and I'm NOT running computer control of air conditioning via PCM. To turn my compressor on, I ran the turn on wire to the compressor and tied that wire into a separate electric fan controller - "Four Seasons pn 35879" for about 35 bucks. My "Classic Air Conditioning" system is still fully protected with low pressure and high pressure safety switches. The Four Seasons fan controller kit overrides the radiator fan temperature sensor via its green wire the instant the compressor kicks in. Compressor on = one fan instantly turned on. You must do it this way to keep compressor head pressures in the proper range. You can't wait for a radiator temperature sensor do this for you.
My Cold Case radiator has two fans and I have two of these Four Seasons fan controller kits. One for each fan. Each fan has its own power, ground, relay, adjustable temperature control and temperature sensor for complete safety and cooling reliability.
Rick
My Cold Case radiator has two fans and I have two of these Four Seasons fan controller kits. One for each fan. Each fan has its own power, ground, relay, adjustable temperature control and temperature sensor for complete safety and cooling reliability.
Rick
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Joined: Dec 2017
Posts: 1,467
Likes: 265
From: Bossier City, Louisiana
Your original Ranger truck harness should remain connected as Ford did it at the factory for the underdash ventilation system. Thus, your temperature ****, the blower settings, the blend doors, the heater control valve and all original ventilation system wiring remains the same.
The GM 5.3 AC compressor in the ventilation system will be operating similar to how the Ford AC compressor clutch operated. However, you need to connect the compressor clutch activation wire to the green wire on the Four Seasons fan controller kit as a "T'eed" off connection. This allows the activation of the e-fans as soon as your AC compressor is commanded on. You cannot wait for the electric fans to come on as the engine temperature climbs unless you want to damage your compressor due to excessive head pressures.
Rick
The GM 5.3 AC compressor in the ventilation system will be operating similar to how the Ford AC compressor clutch operated. However, you need to connect the compressor clutch activation wire to the green wire on the Four Seasons fan controller kit as a "T'eed" off connection. This allows the activation of the e-fans as soon as your AC compressor is commanded on. You cannot wait for the electric fans to come on as the engine temperature climbs unless you want to damage your compressor due to excessive head pressures.
Rick
