I am brand new to the web site and desparate. I have a 1971
3/4 ton ranger xlt camper special that my dad bought brand new and he claims special order. I need to remove the factory installed ac to get to the heater core in the cab. I have located two bolts on the upper right and left side of the air conditioning unit but this is not enough to remove it. Any help would be greatly apprectiated.

 

I'm not sure about your unit- since mine doesn't have A/C- but my heater box has 2 or 3 studs that go throught the firewall. Look at your firewall from your engine compartment and see if you can see 2 or 3 nuts- I think it's 3 now that I think about it.

Good Luck-

Joe

 

I JUST did this on my son's '72 with factory air! Be advised, that "factory" means just that, and it sorta looks like an add-on, but it isn't.
The telling point between factory and aftermarket is that the add-on does NOT have the heater core installed inside; the factory unit is all one integral unit. Also, if the in-dash vent controls below the radio mention AC, then it is from the factory.
You have to COMPLETELY disassemble the entire box to get the heater core out. I do mean completely. Which further means you need to take it out completely and work on it at a bench.
I highly recommend you take it apart and take the heater core to the parts store to match it up. I got 3 different ones before getting the right one.

You really need to work on it at a bench. The back half of the box is made of fiberglass which cracks very easily. Working on it without solid positive control can and will crack it. Don't ask me how I know. I used RTV to seal it though, and it seems to be OK.

To take it out:
1. Remove the 2 firewall bolts.
2. Disconnect the heater hoses from the engine and valves under the hood (you will probably find it easier to pull the hoses through the firewall, rather than connect them after re-installing.) Also, disconnect the AC drain line if bolted to the underside of the firewall.
3. Remove the glovebox, glovebox door and radio (trust me on this one!)
4. Remove the defrost cable on the left (by the driver's right leg) from underneath. This one gets kinked real easily if you remove it later.
5. Remove the cable to the AC switch on top, the one with a 2x electrical plug. (You will remove this switch later.)
6. Remove the other cable on top, to the rear.
7. Remove all the other electrical connections. Fortunately, they are color coded so reassembly is easy.
8. Before you drop it down, remove the 2 defrost hose ducts. You will probably find it easier to remove them from the box, rather than from the dash. If you do not remove them, the 30 year old fabric will tear when you drop the box. Remove them by working the rubber foot out of the hole. It comes easily. This is why you remove the radio, to get to these.
9. Now remove the 2 underdash bolts, and drop it down.
10. Now remove the AC switch above. Be careful of the expansion tube not to bend it too much.
11. Remove the pressure AC line, then remove the valve. You will need to remove the valve to get to the AC return line. Wrenches needed here include up to 1".
12. Once you have it out, you will remove a bazillion 5/16 screws to get to the inside. Reassembly is just the reverse of assembly, both for taking the box apart, as well as putting it back in. It is pretty straight forward.
It took me 2-3 hours to get it out and taken apart, mostly because I was trying to figure it out along the way.
It took me less than 2 hours to put it back together AND in the truck.

Some thoughts about the inside:
Remove the AC evaporator, then remove the rotating flap on the side. You will need to pull this flap's shaft partially out, and you will need to remove the switch mounted above it, just to get the next part out: a flat metal plate.
The heater core is just behind this plate.
Hope this helps!

 

wow! Thats alot of information. I guess all thats left is to get started. Thanks for everything!