Evap & Heater Core Replacement

Need to do the heater core on my '73. I plan on getting the A/C going again before spring so I figure I may as well do the evaporator while I'm in there. Anyone got any experience doing this job? Where to get the parts, seals, diagrams, etc? Thanks,

John

 

I just finished up my heater core in my 77 with factory air. I took lots of pictures because I'm planning on writing a "how to" article. As far as the evaporator, there is really nothing there to go bad unless it leaks. I'm not sure if an air conditioning place can check it out while its out of the car but I'm sure you can come up with a way to pressureize it to see if there are any leaks. Since you have to disconnect the ac lines, there are O rings on the ends of the lines. Most good parts stores carry these O rings. Also while its out remove the evaporator from the metering block and replace the O rings on that side. This will all be in my article. Most of the heater/ac control system is run by vacuum so make sure you mark where each hose goes before you remove it.

 

I'd be interested in this article. I'm gearing up to do the heater core in my '77.

 

I repleced the core in my && without breaking in to the AC system at all, for what it's worth.

 

Ok, how? I didnt see anyway to do it without removing the whole box, but I'm always ready to learn.

 

I split the heater case while it was still under the dash. Dropped the lower out with the heater core in it, left the upper on place with the AC in it, replaced the core and reassembled the case under the dash.

You have to loosen the whole heater case assembly, detach from the center dict work, etc, but you can split it under the dash and leave the AC intact. With r12 going for about $30 a pound, it's worth the work.

 

Sounds interesting. I'll bet those back clips were fun to get on and off. Those were the determining factor on why I pulled the whole unit. Good point though if your ac is a working unit. Luckly I have friends in the business and they just came and sucked out my r12 into a storage container and then will put it back. I have a friend with a 73 w/fact air and he needs a heater core. I think we will try your way on his.

 

While I wouldn't call removing the back clips easy, once you loosen the whole box and pull it away from the firewall, it's not as bad as you think. I was a certified Master ASE Tech, so maybe it seems easier to me.

My next trick will be to try and install heads and a cam this spring without cracking the AC. I might just pull the motor.