Vintage Air Coolant and A/C Leak Test

I’m in the home stretch now as it’s time to leak test everything and then hopefully charge the A/C. I filled the radiator up with coolant and then started up the engine for the first time in months. It started right up and ran at a very fast idle. I spotted some coolant leaks so I shut things down, tightened some clamps. and then started it back up again. I let it warm up until coolant flowed from the engine through the radiator. My IR temperature gun said the temperature at the thermostat was about 165. The choke refused to open so I manually moved the fast idle cam so that the engine could idle. It ran fine and there were no coolant leaks. I shut the engine off and proceeded to diagnose the electric choke not working.

I checked the electric choke wiring and found that the wire connected to the choke was disconnected. I plugged it back in and started the car back up but the choke still wouldn’t open. I checked for voltage at the connector and there wasn’t any. I checked at the stator connection at the alternator and there was voltage. Next I checked the fuse and it was blown. While I was getting a new fuse out of my toolbox I heard a loud pop and saw a geyser of coolant spraying around the garage. One of the radiator hoses had come loose and was spewing burning hot coolant all over. I placed a catch can under the hose and waited for everything to cool down some. Then I fixed the hose and poured the coolant from the catch can back into the radiator. Now the choke and cooling system were both working again.

Next I turned my attention to the A/C system. I connected up my gauges and vacuum pump and pulled a vacuum for 45 minutes. When I turned off the pump to see if the system would hold vacuum it was obvious that it had a really bad leak. I tightened up all the fittings I could get to and vacuumed the system down again. The leak was still there. I removed the hose ends one at a time to make sure I didn’t lose any O-rings. I found that one of the fittings had the nice new shiny O-ring I had installed along with an older one that had come out of the hose end cap that Vintage Air used for shipping the system. I removed the extra O-ring, tightened down all the fittings again, and pulled another vacuum. It was much better this time but still had a slow leak.

At this point I decided to call it a day. I removed my gauges and noticed that several of the gauge hoses had a lot of excess material hanging off of the O-rings for the gauges. I cleaned up the gauge hose ends and tried one last time. Amazingly the system held vacuum. I would have charged it after an hour or two of holding vacuum, but I discovered that the refrigerant can tap I had was the piercing type of tap and my cans of refrigerant were all the self sealing type. I needed to get either a new tap or an adapter, but at this point all the stores were closed. So I was forced to let it sit overnight. While it is a good test, I hope it is OK to leave the system under vacuum for that long of a time.

My next entry should be about charging the system once I have the correct can tap.