Need help with repairing 77' Airstream RV engine AC

[ArgosyRV]

:::UPDATED:::

So... lots to report. system was a disaster. Sorry it took a few weeks for me to get the time and to work on it.

I flushed the system and the lines and condenser were completely filled with trash, complete black mud!

Also, the Evaporator box had the expansion valve in it, it took me forever to find it. Dash board was installed by Airstream after the box was installed on firewall so it cannot be removed without destroying the box or the dash... so I cleaned it with lots of flush in both directions.

System is completely flushed, two gallons of flush through the components to get them clean. New drier, flushed the expansion valve, new A4 pump with 9.5oz of oil in the sump. I was planning on using POE oil as you guys suggested but the new Alma pump recommends PAG. So I now plan on using that.


I will evacuate and charge today and report back. hopefully this pump last longer than 2 weeks!

[ArgosyRV]

Well, success I have 1200 miles on it this week and it is working great. Suggested charge was way too much for the system (4lbs) after conversion I used 48oz initially and it was loading the condenser, checked static charge and I was over 30psi high. Adjusted to suggested pressure and it now works flawlessly, thermostat even works and cycles the pump!


thank you for the advice.

In the end the problem was no doubt pump failure from incompatible oils... it was like salad dressing it would separate and was all foamy...

[bohica2xo]

Thanks for the updates. Glad it is working well now.