AC o ring question (1 Viewer)

[Rigwelder]

I am in the middle of changing out the o rings but haven't been able to find a definitive answer on how many there are. So far I have swapped out 7 o rings, I'm guessing there's 2 more on the expansion valve under the dash?

Rig is a 94 with front air only. I'm also curious if my compressor might be shot, the ac hasn't worked since i got it about a year ago and I'm not sure how long it has been without refrigerant either. It doesn't make any noises or anything so I'm hoping its still good to go.

Any help is appreciated

 

[half k cruiser]

I can't remember how many o rings there are, I have done this job twice. I can give you a little advice though:

Get an entire set of replacement orings from advance or carquest. Then start at one end of the system, I chose the expansion valve under the dash. Work your way clockwise or counterclockwise around, breaking connections and replacing the orings as you go. If you do this you will make sure not to miss any. There are more than 7 for sure.

As for the AC not working, you may not have a charge. Look in the sightglass on the DS front of the engine compartment and see if you can see green dye. Also you can try jumping the low pressure switch ( do a search ) to see if the compressor is working. PM me if you need any more help.

 

[Rigwelder]

I got a kit from oreilly and I'm guessing they are somewhat universal as I have 36 extra o rings now. I know the dryer behind bumper was replaced this winter and those o rings are good but I can't find anymore than those 7 under the hood.

There definitely isn't any refrigerant in the system as stated above it was opened up this winter. So I'm hoping I can change out the rings, get a vacuum on it and have it charged.
Thanks for the info

 

[Tools R Us]

Did you change the big square-ish manifold o-ring? That is the most common o-ring leak that we see. Those kits are generic, have way too many for any given job.

 

[Rigwelder]

Haven't found a square one yet, where's that located?

 

[half k cruiser]

Haven't found a square one yet, where's that located?

You need to take the top off the compressor. Its easy, remove the belt, remove the four bolts that hold the compressor to the block, put the compressor on a bench and remove the four hex bolts to get to the square seal. Also you may as well replace your shraeder valves while you are in their. They are a possible source of leakage and are cheap to change out.

 

[Rigwelder]

Sounds good, i'll do that in the morning. Thank you for the help

 

[Tools R Us]

IIRC, takes a 6mm Allen to remove the manifold and they tend to be stuck, use care, don't strip them, an impact makes it easier. Often, giving each bolt a good smack with a hammer helps.

 

[Ah jroche]

what is shraeder valve, do you have picture

 

[sbman]

This post details replacing the valve cores in the Schrader valve including pictures of them on an AC system:

https://mike-thomson.com/blog/?p=1234

If you have an R-12 system, things might look slightly different. Not sure when the 80 moved to 134

 

[Rigwelder]

So I swapped out the manifold gasket, checked and there was plenty of oil in the compressor and double checked that o rings were good. Had my friend put a vac on it and add 30oz of 134 and my vents are now blowing a nice 46 degrees.

Thanks again for the great info guys, much appreciated

 

[Tools R Us]

Nice!