Bob Needs AC...

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Mace

rock scientist..
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Been driving Bob around for a while and now and it is hott here in Vegas.

AC is the next thing to tackle.

The problem is that it is not as easy as a chevy conversion...

Bob has a 5.0 mustang motor in him. And, the ECU controls the AC compressor..

So, because of that, I have to use the stock ford dryer (it has the provision for the AC press switch). Which is not a huge deal. But as I understand it, there are at least two different designs for AC systems (the in cab part) one utilizes a variable orifice design to alter the coolant temp and the other utilizes a single orifice and turns the compressor on and off to regulate press..

The ford uses the single orifice system.

Does toyota use the same single orifice? or do they have a variable orifice?? I am pretty damn sure that they use the single orifice. But I would be PISSED< if I went blindly ahead and the variable orifice was screwing with the ford AC press switch..
 
The TBI ECM is also supposed to control the A/C compressor, but all I did is use adapter hoses to go to chevy compressor, used a generic dryer & wired the compressor up like stock. Worked fine and the fj60 system has a low pressure switch built into it (by the evaporator I think) and I've been running with the high pressure switch not hooked up for 6 years without a problem. I ran a signal wire to the TBI ecm so it could raise the RPM's but it never worked, so i must have done something wrong.
 
As far as the variable Vs's single orfice, I'm pretty sure that the temp of the evaporator is controlled by turning the compressor off & on (single I pressume). I would wire up the compressor clutch just like stock and skip the pressure sensor.
 
the 60 system does have a thermister on the Evaporator.

Does your compressor turn on and off?

If so, it almost has to be a non variable orifice..
 
The TBI ECM is also supposed to control the A/C compressor, but all I did is use adapter hoses to go to chevy compressor, used a generic dryer & wired the compressor up like stock. Worked fine and the fj60 system has a low pressure switch built into it (by the evaporator I think) and I've been running with the high pressure switch not hooked up for 6 years without a problem. I ran a signal wire to the TBI ecm so it could raise the RPM's but it never worked, so i must have done something wrong.

I was reading in thirdgen and someone was having problems turning the a/c on and off but it ended up just being something he needed to check in the WUD using the EBL. It was in the DIY section... I believe I just brought it up to the top.

the 60 system does have a thermister on the Evaporator.

Does your compressor turn on and off?

If so, it almost has to be a non variable orifice..

"in my best Beavis voice"

heh heh heh, you said orifice...
 
Yeah, my compressor cycles. Pretty much all you are doing is changing compressors and the toyota system controls everything.

Zach,

I'll check that thread out. The only reason I added the signal, was to raise my rpm's while the compressor is running. It was never really necessary, so I never attempted to fix it.
 
I wonder if the computer in the ferd will throw codes then..

Hmm..

I actually think it is a good thing that the Ford computer will not be able to turn the AC compressor Off during hard acceleration :D
 
a land cruiser and most toyotas use an expansion valve to regulate pressures. many fords use an orfice tube. the compressor does not regulate the pressure on any a/c system. the compressor cycles on and off varriying on pressures and temperatures. generally in a hot climate (texas, arizona, vegas, ect) the compressor will be on nearly constantly as the low side pressure stays high enough to keep from freezing things over and therefore wont hit a low pressure cut off.

use teh exsisting land cruiser expansion valve and just add the drier (low side pressure switch) and the other high side pressure switch and have lines made. its not very expensive at all to have em made. you can even have your ford pressor sensors made into your custom lines that way your not creating more hassel and you can still change the switches out if they were to fail.

comprende?
 
I doubt the ECM will throw any codes as it will not know if the AC compressor is running or not.

My compressor still cycled in 115d temps, just more often. The lines on my system were not that expensive.
 
a land cruiser and most toyotas use an expansion valve to regulate pressures. many fords use an orfice tube. the compressor does not regulate the pressure on any a/c system. the compressor cycles on and off varriying on pressures and temperatures. generally in a hot climate (texas, arizona, vegas, ect) the compressor will be on nearly constantly as the low side pressure stays high enough to keep from freezing things over and therefore wont hit a low pressure cut off.

use teh exsisting land cruiser expansion valve and just add the drier (low side pressure switch) and the other high side pressure switch and have lines made. its not very expensive at all to have em made. you can even have your ford pressor sensors made into your custom lines that way your not creating more hassel and you can still change the switches out if they were to fail.

comprende?

define expensive...

If I was going to bypass the ford system entirely (basicaly like it exists right now) Why would I need to use the ford press switch?

I need to look at the wiring diagram for the AC circuit..

All I currently have right now is the radiator thingie and the stuff that is inside the cab. I do have a Ferd compressor too..
 
define expensive...

If I was going to bypass the ford system entirely (basicaly like it exists right now) Why would I need to use the ford press switch?

I need to look at the wiring diagram for the AC circuit..

All I currently have right now is the radiator thingie and the stuff that is inside the cab. I do have a Ferd compressor too..

not expensive... i had a hose made for my truck here locally that goes form the high side of the compressor into the input on the condensor and it cost all of like 20 bux. just use a good hose shop i usually have hoses made as its cheaper than buying something premade... like freaking stupid expensive brake lines.
if your bypassing it then use whatever you want. i recomend something easily available. (duh)
you will just have ford fitting (standard most likely) on one end and then yota fitting on the other end of the hoses.
It really is quite simple. even tho it seems as if it would be complicated.
your expansion valve in the cruiser is under the dash up against the firewall (where the lines come in tho im sure you already knew this) so if that was all untouched then your fine there. Get ya a new a/c drier and connect your condensor out hose to drier and then plug up your compressor and your good.
oh yea and a relay or 2 ya know the electrical part.
its a :banana: maybe a :banana::banana: job. mostly just time waiting on hoses.:beer:
 
The only real benefit of running it through the ECM is the idle up function.


Dynosoar:zilla:
 
bah with idle up. he has a V8 it wont bog it down that much. hell my 60 has the idle up bypassed and it hardly bogs down with the a/c on.
 
Did you ever download the chasis manual on birfield.com? the site is down now but I have a copy if you need it. It has the stock wiring/ system diagrams and exlpanations. Looking at it, all you need to do is connect the compressor wire to the Ford compressor and you are good to go. Everything else should already be in your truck to run the system. Thats how mine is & it "worked" well, I need a new compressor now though.

I think my hoses were about $150, but I can't recal right now.
 
define expensive...

If I was going to bypass the ford system entirely (basicaly like it exists right now) Why would I need to use the ford press switch?

I need to look at the wiring diagram for the AC circuit..

All I currently have right now is the radiator thingie and the stuff that is inside the cab. I do have a Ferd compressor too..


I had my hoses custom made here in Austin for $244.21 (tax incl.) -- this is for 4 hoses, drier & hi-lo cut out switch. This if for Vortec comp to Toyota.

ML
 
I doubt the ECM will throw any codes as it will not know if the AC compressor is running or not.

My thinking is that the ECM will sense the compressor load by idle RPM's. If the idle circuit bypass cannot open up enough to compensate the compressor load, it may trip an idle air command code.

Edit: How is Bob? I read your thread many moons ago and am wondering about his current status? Post a photo on this thread please!

Rick
 
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bah with idle up. he has a V8 it wont bog it down that much. hell my 60 has the idle up bypassed and it hardly bogs down with the a/c on.
I agree.

Assuming you have the stock 60 evaporator, exp valve and wiring harness.
If you unplug the amplifier, and run a jumper between the yellow wire and the black/white wire, when you push the A/C button, the compressor will engage.

The amplifier, thermistor and pressure switch will be out of the loop and expansion valve will take care of it all, and you will have a working A/C system.

You won't miss the amplifier, as stated above you won't bog down, or shake at idle with the V8.

You probably won't miss the thermistor since it's rare the evaporator will ice up unless you are running the A/C when the outside ambient temp is below 75 degrees.

The pressure switch isn't necessary, but is a safety feature to prevent the compressor from engaging if you are trying to run the A/C system when there isn't any refrigerant (thus no lubricant) circulating. You could always wire it back up in line between the switch and compressor.
 
I agree.

Assuming you have the stock 60 evaporator, exp valve and wiring harness.
If you unplug the amplifier, and run a jumper between the yellow wire and the black/white wire, when you push the A/C button, the compressor will engage.

The amplifier, thermistor and pressure switch will be out of the loop and expansion valve will take care of it all, and you will have a working A/C system.

You won't miss the amplifier, as stated above you won't bog down, or shake at idle with the V8.

You probably won't miss the thermistor since it's rare the evaporator will ice up unless you are running the A/C when the outside ambient temp is below 75 degrees.

The pressure switch isn't necessary, but is a safety feature to prevent the compressor from engaging if you are trying to run the A/C system when there isn't any refrigerant (thus no lubricant) circulating. You could always wire it back up in line between the switch and compressor.

exactly how my a/c is set up and i have no ice problems with compressor running all the time and when the outside air drops below 75* or i begin to get cool in the cab i will manually turn the a/c off for a short period then turn it back on. i have left it on before at liek 70* runnin down the freeway and still no ice.
 

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