AC Rebuild - Part 4 - 09/15/2015

The day has finally arrived. The moment of truth. Over 48 hours without budging from vacuum, the system is sealed and is extremely likely not going to leak. Time to charge it up, verify it works, and enjoy the fruits of our labor.

Set everything up, 30lb jug of freon, scale for measuring, gauges to feed and monitor.

One thing that helps this go quicker: bucket of warm water to keep the refrigerant from icing up internally.

4.3lbs of refrigerant later, it's charged and full (4.25lb system per the books). With the engine running the compressor engages just fine, pressures equalize to 35psi low and 180psi high, which is pretty standard R12 operating pressures at 75F or so outside.

Temperature gauge shows a little over 45F. Not bad! I think we can do better though...

The evaporator lines come out of the case and are open to air.

Cold refrigerant is through this tube.

Giant hole down here, the AC will be fighting the engine heat getting in and the blower motor blowing out air through this hole.

AC sealing tape is molded around the hoses. There was some originally before I took it all apart, but it was broken and missing chunks so time to do it over correctly.

Top hole plugged now too.

While I'm at it, the fan is marginal. It spins around a few times when hot, which indicates it isn't any good anymore. So I put a spare good fan on. All of the grime around the sensor on the old fan is because the fluid inside that locks it up has started leaking out!

Hard to tell due to the lighting and angle, but it is just below 40F now. Downright frigid!

Definitely satisfaction of a job well done here. It blows cold and is staying charged without issue. The new Pro6ten compressor doesn't drag the engine anywhere near like an A6 does, you can definitely tell the difference in performance between the two. Considering the cost difference between a rebuilt A6 and a new Pro6ten is only $150-200, why not just go ahead and upgrade unless you have a show\numbers car? Just my thoughts...

Return to 1973 Grand Safari

Last updated September 15th, 2015