Hey Everyone.  I started working on the Heater/AC system of the Vette when I noticed some coolant leaking from the Heater Core supply line (from the water pump)  Thankfully the core is good...just a small hole in the hose...However while I was tearing into the car I decided to undo some teenage back-yard mechanics that had been done to the AC system.

This is how the system was rigged...it is definitely a mess.

This is my mystery piece. I have no idea what that is...any idea's??  It is connected to the AC line with hose clamps..and was wrapped with Axle Grease and Aluminum foil

Finally...is are there any rubber fittings to seal these holes between the lines and fiberglass case??  Again..these were jammed full of gasket sealer, axle grease, and aluminum foil. If you are not able to view the links, let me know.   Hope everyone had a great holiday season. -Shane


(corrected links)Adams' Apple2009-01-06 20:38:48

That looks like a capillary tube & relay. I would guess the two wires are going to the A/C compressor? It's function would be to cycle the compressor depending on the temp of that line. When it gets cold, it should cut power to the compressor. As it warmed back up a little, it would close, and kick the compressor back in.
The hose clamps are, believe it or not, the normal way to attach the tube to the A/C suction line. That line should be insulated, tho, and it prolly was, at one time.

The last pic, yes, there should be a "grommet" of sorts in there, as well as some of that really neat tar-based sealing putty. The stuff that just gets everywhere anytime you touch it...

I don;t know for sure off the top of me head what particular system a '79 would have, but that may be the factory set-up...
I'd have to look in a book...
I bet someone here will know...

Thanks Adam. I'll leave that temp "thingy" where it's at and insulate the tube.

To fix the leaking problems I'm having I've decided to replace all the stock rubber hoses with stainless braided hoses. I'm definately an amateur and it seems that the braided racing hoses are not sold in standard measurement...so does anyone know what "AN" sizes i will need??

Definately looks like a temperature relay - If it aint broke - don't fix it - As for rubber grommets- yes and the gooooy stuff Joel refers too

As usual Joel is right about switch. Actual name is Thermostat Cut-off Switch. Designed to do as Joel said, cut-off compressor when certain temp. is reached, thus keeping the pressures within proper range. Now in the pic you will see two little dents in liquid ( high pressure line). This is where the orifice tube is, which releases high pressure and turns ref. into low pressure liquid (cold) before going into evaporator. In later years they use a Cycle Switch located in the side of accumulator. I thought by 79 they had done this , but I may be wrong.

my7T12009-01-07 14:24:44

Thanx, Terry...I couldn't remember what they called that "thingy"...

Shane, Terry and Joel were on the mark. The temp sensor really should be cleaned up, as well as the tubing surface. You can use mineral spirits to clean it all up. After cleaning, you need to brighten the bulb and tubing with a Scotchbrite pad or steelwool. This allows for optimum heat transfer. Reclamp it with the hose clamps, tighten it securely, but don't over tighten to the point of distorting the bulb and tubing. You then insulate wrap with the cork/tar tape insulation. Wrap it about two and half times. Here is a link to the insulation tape called Presstite:   http://www.gsistore.com/prestite-pt1-tap.html 

Awesome. As always, everyone here is extremely helpful....especially for a amatuer like myself who is learning as he goes.  I'll post a pic after I get it all cleaned up and installed. Thanks again guys.