02 Tahoe a/c w/ rear air control

[donmauldin]

Purchased an Four Seasons A/C kit consisting of the compressor, orfice, accumulator, oil, and "O" rings for the '02 Tahoe.
Couldn't remove the old orfice tube as it kept breaking apart, so I purchased a new coolant line.

There was zero pressure in the system before repairs as my compressor had very low pressure.
Fast forward 3 hours and after installing everything, replaced all the "O" rings at every connection, filled the required oil in everything, I can't pull a vaccuum. .
Apparently there exists a leak somewhere.
I opened the rear a/c condenser box and haven't seenany oil leakage.

My question is do I need to be able to pull and hold a vaccuum before interjection of dye to find the leak. Right now the system is completely empty of refrigerant.

I did not replace condensers in front or rear nor have I replaced the rear expansion valve in the rear.

Where would the most common leak be found??

 

[Tonyrodz]

I've read if you're in a salty state, the rear ac line is prone to leaking--what I've read anyway. Might want to check there.

 

[donmauldin]

I've read if you're in a salty state, the rear ac line is prone to leaking--what I've read anyway. Might want to check there.

Thanks. I'm in North Carolina north of Charlotte , I have the rear air box apart and there's no corrosion.

 

[exp500]

Put a little pressure in it and soapy water spray bottle.

 

[donmauldin]

It will not hold pressure. Sprayed all joints and connections, and no leak. My only suspicion is that the evap is leaking. I apply pressure and as soon as I remove the air the pressure drops to zero

 

[exp500]

Don, thats a huge leak! You maybe could hear it unless as deaf as me. Try spray bottle again, spray seams and tube connections- hell just spray everything, it will blow bubbles or foam trail. Those shop towels around the rear will soak it up. A leak that big has pushed some oil around to the leak too. Sounds like you forgot a gasket hopefully.

 

[donmauldin]

After process of elimination, I took on the task of removing the evap. I could hear air but thought it was just the air circulating . After removing the evap i found the leak. I ordered a new core and hopefully that's the only leak remaining.
I will post a follow up.
ThanksView attachment 278603

 

[Aquamania001]

Good you found it so quickly.

 

[montegutman]

After process of elimination, I took on the task of removing the evap. I could hear air but thought it was just the air circulating . After removing the evap i found the leak. I ordered a new core and hopefully that's the only leak remaining.
I will post a follow up.
ThanksView attachment 278603 View attachment 278604 View attachment 278605

Donmauldin,
How difficult to get the evap. out? I replaced all four indash door motors this last spring and was a major pain. Found originals were all still good just saturated in grease. Have had my 2005 Yukon XL LT K2500 since new. Now has 85K miles. Plan on being buried in it.
Will replace the A/C compressor, dryer, ex-valves soon as the system is original. Compressor low side is running way too hi, so am certain it is time for replacement before it blows scattering metal fragments throughout the system.
Appreciate any advice you may give,
montegutman

 

[montegutman]

Donmauldin,
How difficult to get the evap. out? I replaced all four indash door motors this last spring and was a major pain. Found originals were all still good just saturated in grease. Have had my 2005 Yukon XL LT K2500 since new. Now has 85K miles. Plan on being buried in it.
Will replace the A/C compressor, dryer, ex-valves soon as the system is original. Compressor low side is running way too hi, so am certain it is time for replacement before it blows scattering metal fragments throughout the system.
Appreciate any advice you may give,
montegutman