Re: 1979 Chevrolet C70 Conversion to OEM Air Conditioning
 

Thanks, I tried to use the number shown and did not get anything to come up.

Re: 1979 Chevrolet C70 Conversion to OEM Air Conditioning
 

Got some more done, installed driver side A/C vent. This vent uses a plastic molded section that routes the vent duct below the steering wheel. You can see the plastic u shaped duct under the steering column. The duct that feeds the driver side vent also feeds the driver side right vent. Once these are installed you will need to position the driver side defrost duct and attach the end on the driver defrost outlet.

Re: 1979 Chevrolet C70 Conversion to OEM Air Conditioning
 

Next, positioned the right end of the center duct in the upper portion of the dash. Then move it aside and install the defrost door housing. Before installation I replaced the door foam seal. When installing the defrost door housing, connect the passenger side defrost hose going between the defrost vent and the housing. Defrost housing slides under two clips on the heater housing and is fastened in place by a screw on the right side. Connect the vacuum line to the actuator and then install the right end of the center duct using two screws one on each side. The center duct is held in position by two metal tabs with screws through the dash frame.

Re: 1979 Chevrolet C70 Conversion to OEM Air Conditioning
 

Here is a picture of the foam installed on the defrost door.

Re: 1979 Chevrolet C70 Conversion to OEM Air Conditioning
 

Installed the dash vents to the dash pad using six plastic nuts. Installed new foam seal on dash duct. Installed A/C Heat control, hooked it to both wire and vacuum harness. Note, I removed the radio before installing duct work to give me better access. Installed padded dash and instrument cluster bezel.

Re: 1979 Chevrolet C70 Conversion to OEM Air Conditioning
 

nice job :D
amazed that gm had 2 firewalls for a truck ac and ac delete

why you didn't convert it over to r134?
all you had to do was solder in a new expantion valve
then go with a new compressor, dryer and hoses

Re: 1979 Chevrolet C70 Conversion to OEM Air Conditioning
 

Thanks, yes I am planning on converting it, I have flushed the oil and have adapters to go on the low and high side ports. I am going to make new hoses that will be the barrier type for 134A.

Re: 1979 Chevrolet C70 Conversion to OEM Air Conditioning
 

Next I installed the A/C configured glove box. I had to change the plastic pocket from the donor door to my original door. This ended up being more difficult than I imagined. The lock has tumblers that have to be released. This is accomplished with a paperclip inserted into the hole in the release knob. Once the tumblers are released then you pull the knob and tumbler assembly out and remove the retaining nut using a hex wrench. Remove the four screws (2 each side) and bend the metal tabs on sides of the glove box door outer metal shell. This will give clearance so the plastic pocket will slide out. Reverse the process to install the A/C style pocket.

Re: 1979 Chevrolet C70 Conversion to OEM Air Conditioning
 

Installed the lower heater vent today. This vent is attached with a small screw on the passengers side and a bolt with rubber grommet on the drivers side. Note the forward edge snaps to the edge of the heater housing prior to installing the small screw.

Re: 1979 Chevrolet C70 Conversion to OEM Air Conditioning
 

Awesome write up, thanks for the level of detail!

-Richard

Re: 1979 Chevrolet C70 Conversion to OEM Air Conditioning
 

Got some more done on the A/C conversion. I installed the vacuum controlled hot water shutoff valve. This valve stops the flow of hot water to the heater core when you select max cold on the temperature control. Settings other than max cold allow the heater core to operate to provide blend air for temp control.

I also got some more done on the interior. I installed a new dash pad and door cards. I purchased the door cards from LMC. They fit and look awesome.

Re: 1979 Chevrolet C70 Conversion to OEM Air Conditioning
 

Did the dash pad also come from LMC? What color did you specify? That looks like what I need.

Re: 1979 Chevrolet C70 Conversion to OEM Air Conditioning
 

No, I purchased it from Classic Industries, it is Carmine red. It fits real good as well. Just be sure to save your clips from the old one.

Re: 1979 Chevrolet C70 Conversion to OEM Air Conditioning
 

I need a new dash pad and door panels for my 77, and the original color looks like what you installed. I have been watching other people's projects to see how the look and where they got them before I buy any. Yours looks like the right stuff. Thanks!

Re: 1979 Chevrolet C70 Conversion to OEM Air Conditioning
 

1979 C65 really low mileage ex-firetruck. Looks like dealer add-on A/C, maybe this will help you.

Re: 1979 Chevrolet C70 Conversion to OEM Air Conditioning
 

Great job, I have done this changeover and small fingers really would help! Where are you planning to get the vacuum to operate the controls?

Re: 1979 Chevrolet C70 Conversion to OEM Air Conditioning
 

I was able to tap into the line that feeds the vacuum gauge. The truck has vacuum boosted brakes which is supported by a Bendix engine driven vacuum pump. Thanks for the pictures.

Re: 1979 Chevrolet C70 Conversion to OEM Air Conditioning
 

Got the A/C compressor bracket installed, next will mount the actual compressor and belt.

Re: 1979 Chevrolet C70 Conversion to OEM Air Conditioning
 

Mounted the compressor and installed the condenser. Condenser bolts directly to the radiator support with 4 small bolts.

Re: 1979 Chevrolet C70 Conversion to OEM Air Conditioning
 

Got the connections to the condenser installed. I noticed these lines are steel on the medium duty trucks and aluminum on pickups. Guess the steel take vibration better.

Re: 1979 Chevrolet C70 Conversion to OEM Air Conditioning
 

Got some more done on the truck, reinstalled the seat and seatbelts. Next is installing the a/c lines from compressor to evaporator and condenser.

Re: 1979 Chevrolet C70 Conversion to OEM Air Conditioning
 

It's so rare to see a medium duty looking so good. Love the updates, thank you for sharing your work.

Re: 1979 Chevrolet C70 Conversion to OEM Air Conditioning
 

Thanks, I appreciate your comment.

Re: 1979 Chevrolet C70 Conversion to OEM Air Conditioning
 

Started disassembly of the truck to repaint the exterior back to its original color. Upon removal of the right side (passenger) fender extension I discovered a rust problem between the extension and support brace. Water had collected over the years and caused the fender extension metal to rust away in the vicinity of the support brace. My son Noah assisted me in removing the rusty metal and welding in new replacement metal. It turned out real good. He plug welded the brace back onto the extension and it's ready for primer and finish sanding.

Re: 1979 Chevrolet C70 Conversion to OEM Air Conditioning
 

Hey, good to see an update. Glad you're still making progress on it. Is that brown color the original you refer to? Will you and Noah be building the flatbed for it as well? Dovetail or straight? I went back through and read the first post...this tractor collection you speak of, I hope there is some green in there. :D :D :D