98 explorer AC issues

[Shifty Hooligan]

.I bought a 98 Eddie Bauer from a guy on craigslist and was a little too eager to hand over my hard earned cash, so have been chasing issues as they pop up but am still stuck on the AC on this rig. It was not blowing cold air and the clutch was not cycling at all. I added about 9 oz of R 134a but the compressor never did kick back in so i stopped.
I bought a manifold gauge set and bypassed the low pressure switch and looked at both high and low pressures. Only had the compressor bypassed and running for about 10 seconds. The low side is reading 30lbs and the high side is reading 50 lbs.
I am assuming i am plugged up and need a new orifice tube and accumulater/dessicant bag. Am I thinking right or is there something else I should be looking at? I am brand new to AC diagnostics and have learned lots here and also from watching videos.
Also does the system have to be emptied to replace those items?

 

[fixt]

The pressure reading of R134a is temperature dependent at static (no load) condtions. If I am remembering right my low side pressure is about 38 psi running at around 90F at 1500 rpm, I don't remember high side pressure. Vent discharge temp was at about 41F. My under hood sticker says 1lb 14oz. V8 XLT package. Since about all systems leak to some degree I just top mine off or check once a year beginning of summer.
Check your low side and high side valve covers for their gasket o-rings inside and make sure they are on hand tight, its part of the system seal boundary
There's lots of R134 charts floating around the internet tubes should you need one.
It sounds like you are low on R134a. Do you suspect a leak? I mean, it went somewhere at sometime right?

If its a bad enough leak you would also need to replace the system oil that probably blew out and if you're going that far it would be time to replace drier/accumulator and orifice tube after the leak is repaired and a good vacuum has been established and held.

 

[koda2000]

Also be sure to check the A/C relay and any related fuses.

 

[Shifty Hooligan]

All AC fuses and relays checked and good.High and low side gaskets checked out and are tight. I agree that it is low r 134a but just bought this vehicle last month so do not really know its history. Taking it next weekend to a shop and they are going to do a draw down and diagnostic on it. Depending on how bad it leaks down in a half hour i will decide what my next step is. If I have to replace parts then I will do it myself then take it back and have it refilled with oil and 134a. Thanks for the reply, will try to update next week sometime.

Edit: If I have to open up the system I will be replacing orifice tube and accumulater before taking it in to be refilled.