Bypass your heater core lines, use a switchable bypass valve like an old Chevy, These cars are getting old and blend doors are not working/sealing very well, your vent temps will drop 20 degrees. Also for Christ sake stop messing with your ac system and take it to an AC pro.
Evac/Pull 30 inches of vacuum for 15 mins/Chage with proper WEIGHT. I have seen low side pressures vary from 50 lbs to 30 lbs depending on ambient temp and condition of fan clutch. BTW using low side pressure as a measurement for system fill is retarded. Please tell me what car manufacturer says "fill ac pressure to 30 PSI on low side".

 

mike you thinking of the orifice tube? those tend to clog up and should be replaced everyime you replace somethin else in the ac system lol

 

X2 on vac and refill... you could have air in system, and let a pro do it if you don't have gear

 

if the pressures fine and the compressor clutch is doing its job, consider this:

if its cold while moving the condensor might be gummed up from mud, bugs, road debris or have damaged fins. at speed you might have enough air to cool it down and let the system work, but not at idle speed. its basically a mini radiator that the r134 goes through during its compression/decompression phases. in a home ac, its the big box that sits outside with the big fan on it to keep it cool. the cooler you can keep it, the better the heat exchange, the colder the air you feel. thats why people dont notice thier ac doesnt work in spring/fall or winter, cause it will blow cold air fine! during the summer when it cant exchange the heat due the hotter external temp, its performance drops, especially when sitting in traffic or if the things damaged. while moving theres enough air so that it can function properly. check to see that its in good shape, clean off any dirty, bugs, mud and use a soft leather glove or the like to hand remove any corossion thatll appear as white crusty specks. get a cheap radiator fin repair comb, plastic haircomb looking thing that you can use to strighten out damaged radiator fins, the usually come with sever sizes, ones bound to fir the ac one.

start free and cheap

also, im not sure if the discoverys have a seperate fan jsut for the condensor, or if it uses only airflow, or if its mounted so to use the engine fan as its fan. they are usually mounted like an intercooler or power steering cooler, behind or infront of the main engine radiator to borrow the airstream and cooling fan capacity.

 

they have electric fan

 

I understand you are a mechanic and all, but anybody who had ever read the 2 pages on our D2 t/stat and heater core knows, with the heater hoses by-pass, especially in the summer, your coolant system will loose a 15% plus amount of cooling efficiency. So that being said, read it if you don't believe me then don't doe this mod.

 

checked out the condesor from behind the grill and it looks to be dirty & bug laden- most of the fin area looks intact minus what a pebble here or there had done- i plan to use some simple green and a garden hose to see what it'll do

 

It should have a sight glass around or near or on the reciever dryer.
It should be clear when the system is runing and fully serviced. If it is cloudy while running then freon is low. If you cant get the cloudyness to go away then a evacuation and new dryer a. Are needed
Not to mention new
Freon. Neil

 

Russ clean out condenser before more work is paid for

 

Those readings on the gauges can mislead.

1) Never hook to the high side. You are not a professional. Neither am I.

2) On the low side - put in a little.

3) Use a meat thermometer and look at the output temps from the A/C.
50 to 55 degrees. If you can get it lower, then good.

4) If you have in too little - your compressor always runs and you have warmer air.

5) If you put in too much, the temps also rise and the compressor goes on and off a lot at idle as you overfilled it.

6) When it is hot out and you are on LO then the compressor should always spin.

note-
I used this method and just drove 1531 miles in 100 degree heat.
A/C worked like a champ.

I did overfill and had to evacuate some extra freon.