Do you need to vacuum out the system before you recharge the system?
I had to take off a line, so the system is discharged now.

 

yes, it won't ever get as cold if you don't. It really needs to get down to 29.6 in hg to boil out any moisture. If the system hasn't been open long you can get a cheap pump from harbor freight that will go down to about 26. This won't get the moisture, but will get most air out and will cool pretty well.

 

...absolutely YES!...pump it down for at least an hour to give any moisture time to "boil off"....if you are (i hope) using a set of refrigeration gauges, pump the system down and shut the valves on the gauges notating what the readings are.....come back in an hour or so and if they have moved, you have a leak that MUST be fixed....

...how long was the system opened up for?....you might as well replace the accumulator tank and change out the orifice tube as it works somewhat as a filter and as a metering device....

 

Agree and technically as I'm sure some of the forums "Book Readers" will state you should replace the accumulator any time the system has been opened---I don't replace myself unless i know the system has been opened multiple times and/or that it is bad--and depending on how the charge was removed--such as discharging VERY rapidly--you likely lost some AC oil --you would need to add a couple ounces of oil.

 

I'd replace the Accumulator. It's a Vette, but even if was the family Yugo, it's an opportunity to make it better than the Factory. When it was built, the line wasn't stopped to get it charged, or to check the vent temp - it's strictly a pump and dump operation. The compressor doesn't run until the car is started for the first time and though anything since '90 has a pressure sensor which gives the tester the high side, that's about it. But more importantly, the OEM's rely on the desiccant in the Accumulator to soak up any residual moisture that was left in the system and that at least gets it through the warranty - at which point, if it blows up, the Dealer hopes you trade it in on a new one, especially when you get the $3000 estimate for a rebuild. So take your time, replace the Accumulator and clean out the orifice, add the factory oil fill and then pump it down for an hour. If you're really nuts (like me), let it sit overnight to make sure the vacuum holds and then charge it up. I allmost guarantee you that you'll beat the Factory vent temp and with the right parts, it won't blow up on you (again).

 

The accumulator is almost new, I changed over to R134 about 6-8 months ago. So, should I still change it?
The hoses were off for a good part of the day, so I am going to vacuum the system.
Thanks for all your help!!

 

....if the system was opened for any length of time (quote;The hoses were off for a good part of the day), you should replace the tank....if you plan on switching refrigerants to something other then what the tank was installed/used for then you MUST change the tank....

 

Will replace the accumulator,how much oil do I need to put back in the system?

 

Was looking at accumulators and found this one for converting to r134, do I need this or is this a gimmick?

http://www.autozone.com/R,APP264907/...FCE0AA87A94F58

 

Usually when the say universal they mean it will work with either gas. I don't know if that's the correct model for your Vette, but it doesn't look like anything I've seen. You should be able to find a direct replacement though if you're '91 or below, the GM replacement requires that the bracket be notched for it to fit as it comes with 2 schraders instead of just the one. You might try NAPA or The Last Detail - www.tld-corvette.com

 

How much oil?

 

8 ozs; either gas. Assuming there's one oz still in it, I'd put 4 in the compressor and 3 in a new Accumulator.

 

Thank you!!!!