[QUOTE=hasteranger;9087864]guess thats what I have to look forward to if mine ever fails! Lucky that you had R12 around. I've heard its still available in mexico...[/QUO i buy r12 here in az at brown and brown chevrolet. i have my 609 cert so im legal to buy it

 

I replaced the heater core on my '78 with factory a/c from the inside a few years ago, and all I took out of the box was the heater core. A couple of parts guys at a GM dealership told me it was possible - just look for 3 small screws inside the box, remove them, and very carefully pull the evaporator tubes back to remove the heater core. I don't remember what the screws hold in place, but you won't see them unless you know to look. There's not much room, and you have to be extremely careful, but it can be done. I took the seat out so I could sit on the floor and look straight in instead of twisting around and standing on my head.

 

How long did it take you? I have a 79 and right now I dont have the heater hoses hooked to the tubes at the firewall because they were leaking so I just cut them and routed to both parts of the engine. I HOPE that the original owner had it done some time in its 30 + year history! LOL I will find out soon enough when I put new hose on.

 

I really don't remember how long it took. That was at least 15-16 years ago. I probably took half a day working slowly. The most work was removing and reinstalling the seat without help, but the effort was worth it to be able to look right in through the glove box. Of course, the seat hadn't been in long as I had swapped it in not long before that, and wasn't stuck down like the original had been. I don't think the actual work of changing the heater core took all that long. I remember taking a long break after I got the core changed before I put the seat back.

 

Ok, well we will see what I need down the road. Maybe I will be good and not have to replace anything for a while.

 

I just did mine in my '79 without A/C. It took longer to burp the air out of the system than it did to put the heater core in. It took me about 25-30 minutes start to finish.

 

How did you replace in in a half hour? Granted mine has A/C, but wow! I'm going to have to do this in the Spring and welcome advice to help me not spend a day+ on it.

 

It must be way different. There's 3 nuts on studs that go through the firewall under the hood that hold the heater box to the firewall. Undo those and the heater hoses. Then go inside and take out the bolt in the bottom right hand corner of the dash. Pull the heater box away from the firewall and pull out on the bottom of the dash. Theater box will flop on the floor. Pull the two cables off for the heater controls and the box slides out. There's 3 sheet metal screws that hold a tin plate on the box where the heater core is. Take those out and the heater core falls out. Reverse the process to reassemble. Like I said, it took me about 25-30 minutes.

I was actually dreading the job. I did the heater core in my wife's Intrepid about a week earlier and it took 6-7 hours. I had half the car disassembled and laying on my trailer. THAT car was a pain. The truck was cake to do.

 

Doing the heater core on an AC truck and non-AC truck is TOTALLY different. There is pretty much no similarities at all.

 

I figured as much. I don't think ANY of the dents I've owned had A/C. It was never that important to me I guess, and I never came across one for sale with it in there. (that I was interested in buying)

 

A/C vs. non-A/C are two totally different animals. Non-A/C rigs can definitely be done in under a half hour. A/C rigs take about an hour and a half front gathering the tools to clean up at a decent pace. Here's a good write-up to point you in the right direction:

NORTH COUNTRY SPECIALTIES ®

 

After reading all the stories I was not looking forward to doing it but I didn't find it all that bad.

I wanted to check my fan motor so I pulled the entire box out from under the hood and it only took me about 45 min to get it completely apart. If you don't want to look at the motor you don't have to remove the entire box and it wouldn't be bad at all.

 

The non-A/C sounds nice. Oh well.

I'll take a look at that when I have a moment, 704 dentside man. Thanks!

Kevin316, what year etc did you replace it on?

My A/C fan (passenger feet) sounds like it's rubbing on something. Not sure if I need to replace that when I'm in there or not. Anyone do anything like that while you were down there?

 

704 dentside man, those instructions say that they cover "73-79 F Series and 78-79 Bronco" but it looks like the heater core is in the engine compartment in those instructions and mine ('78 F-250 w/AC is in the cab behind the firewall. Are you aware of any similar instructions that would cover my application? I'm not sure why these instructions say they cover my vehicle but it's not the same.

 

Amidst all the arguing in the beginning of this thread is some great info. Replaced the heater core in my factory a/c 78 in just over 2 hours. Not to difficult if you have the correct info - the North Country Specialties link as posted by Ranger429 and others. I look forward to seeing through thawed windows next week when hunting season starts.