Aggie007

1999 Ford F250 with '04 CTD Automatic

I had my a/c lines made and charged the system. The pressure gets real high because the Cummins fan isn't pulling enough air across the condensor. This is because the A/C system is Ford controlled while the fan is Cummins ECM controlled. How and what wires do I need to send to the Cummins ECM to let it know the a/c is on and to lock up the clutch on the fan?

ramman

I will have to research the prints before I could begin to answer that as it will also affect me whenever I get to do my 05/05 swap.Do you have the electronic ac control?

5.9Excursion

I will hopefully be trying to get my A/C hooked up this weekend, I'll see what I can come up with for wiring...

What did you do for A/C lines? Splice the two together or something new?

Aggie007

I am installing electric fans to come on when the a/c is on, they will be pusher fans in front of the condensor.

I bought the a/c lines from Dodge just to use the manifold to the compressor and had the dodge manifold mated to the ford lines. Literally took my guy 5 minutes to cut and recrimp the lines.

5.9Excursion

So did he cut the aluminum tube off and then recrimp to it? Or cut the old crimped piece of the hose off and recrimp it there?

I took my lines to a few places and no one could recrimp with the same style of connections. I was planning on cutting the aluminum lines where necessary and having someone local weld the two together (aluminum sections of the lines).

Aggie007

He cut both the ford and dodge a/c lines behind the crimps removing the crimp and hose. With new hose and hardware, recrimped the ford and dodge a/c lines together.

BearKiller

Simplest best A/C is to lose the Dodge compressor and keep the entire Ford A/C intact.

I didn't even bleed off the refrigerant; I simply layed the compressor over on the fender, swapped engines, built a simple bracket, and remounted the compressor.

I dis-like the Dodge compressors and especially where they are mounted.

As for the fan-clutch, a direct-drive fan is best; you won't lose any noticable power/mileage with a direct-drive fan cause these ain't little wimpy lawn-and-garden engines.

With a direct-drive fan, the A/C blows just as cold idling in traffic as it will at highway speed.

Hammily

Does anyone have their Dodge AC working in their Ford yet?

5.9Excursion

Almost, I just had my AC lines spliced together. Much more complicated getting the AC lines routed on my Excursion than on a F250 (from pics I've seen). Regardless, I looked at the wiring and the compressor will still be run by the ford computer I just have to splice the ford wiring into the dodge compressor wiring.

However, the fan needs to speed up when the AC system is running, it appears as though the ECM monitors the AC system pressure and regulates fan speed based upon the pressure. I thought about how to wire it to get it to work and it seemed easier to just have another dodge pressure sensor and bung welded into the line (the ford and dodge pressure sensors are different types). I picked one up from a salvage yard and now need to get back to my aluminum welder guy to get the second bung welded on.

This way the ford will control the compressor and monitor system pressure with the ford pressure sensor and the dodge ECM will monitor system pressure with the dodge pressure sensor and regulate fan speed...

Hope to have it all finished in a couple weeks...

Aggie007

I have been driving my truck for over a month now with the a/c. I had to put electric fans pushing on the front of the condensor too keep it cooler so it doesn't over pressure cuz I don't know how to let the dodge ECM know to lock up the fan. My a/c blows 38* in 100*F heat. My trans never gets over 155* either.

5.9Excursion

where is your tranny temp sensor located? Mine is located in the hot line coming from the tranny (just after the torque convertor) and it reads plenty hot in the heat while in town. Down the highway it's only 140 or so, but in town it will shock you... I'm temped to install another sensor in the pan to see what temperature the tranny internals are seeing.

Hammily

Aggie007 how did you hook up the wiring to make it work?

Mo Smoke

I have mine working, I cut the Ford and Dodge lines at the mating blocks where the compressor mounts to the manifold and used a refridgeration flairs to connect them, and the wiring is like a daiseychain from the dash control 12v to the LP N.O. switch to the HP N.C. switch to the compressor clutch coil. Ground the other side of the coil and it draws 10A.

Aggie007

I put the Flex-a-lite 230 dual pusher fans. I was going to install the a/c/temp control unit which comes with the 240 kit, but my a/c is always on and if its not I probably still want the fans on for the coolers. It fits perfect between the grille and condensor. I have it mounted to the core support with some simple "L" brackets. Since I live in Texas, and its hot here, even the roads (highways) are over 130-140*F during the day, so I just wired the fans using a 30amp relay, with an ignition on feed. I have a switch on the dash so I can turn them off if I am parked listening to the radio or for the two weeks a year it gets below 60*. The fans are pretty loud though, when they are on you can definitely tell it. You can here them in the cab, but my turbo still drowns it.

My transmission sender is in the side of the transmission so it is giving actually working (internal) temperature. Before the fans I have seen 200* just driving a short distance in town, and 160* on the highway. Now its 155* in town and 150 on the highway.

jtharvey

Did you get this working? I started looking at all my AC stuff tonight and am a little confused. Do I need to keep the Ford pressure sensor in the line...are the threads in the bung the same for the Ford and Dodge sensors? I know the electrical sides are different. I've got the Dodge lineset, so I do have the bung on that one I can use if needed.