Revisiting truck AC issue

[Knoxtnhorn 6066]

At the end of last summer, my truck AC began to take longer and longer to blow cool air.  I'd be 10 mins into a drive before it cooled.  

I topped out the unit with Freon, and things seemed fine; however, I only probably ran it for another couple of weeks before the weather cooled.  The problem has begun to recur this summer.  

One thing I've noticed is that it seems to struggle with higher ambient temps.  On the way to school, it blows somewhat cooly rather quickly.  In the afternoon (90's) it struggles to overcome the higher temps.  It'll be 15 mins before it blows cool enough to bring the cab temp down.  Even then, it's not super cold.

Anyway, just wondering if the specific issues noted are enough to possibly pinpoint what I'm dealing with.  As you can see, I know next to nothing about vehicle AC systems.  I'd, at least, like to sound like I know what I'm talking about if I need a mechanic.  Thanks in advance.

 

[Bevo&Pevo 5222]

Sounds like a leak for sure.  If ya' planning on keeping it, then I'd go get a "real" fix.  The other option is top off with freon until it leaks out again.  Question is how long will that take? 

[Gil Bang 26049]

What are you paying for freon out there?   If it's cheap enough, you can keep adding it, or, you can have it fixed properly. 

[Jkwellborn 6749]

Make sure the the valves on the hoses seal up like they’re supposed to.

What vehicle were we talking about again?

[tx 3 putt 77538]

Where are you at ?

my car needs a shit if freon

 

[Bevo 13601]

I feel your pain - $1800 to fix my AC last week

[Jerry Callo 8734]

On 5/20/2023 at 8:59 PM, Jkwellborn said:

Make sure the the valves on the hoses seal up like they’re supposed to.

What vehicle were we talking about again?

This is a good first step.  Run the a/c and then pull the caps off of the high and low pressure values.  If there is moisture in the caps, you need to have the valves replaced.  

I installed a cut-off valve for the heater hose in my truck.  It takes longer to cool the cab if you have hot water running through the cab in the summer.*

*ETA - your truck is likely not 54 years old, so you might not want to start messing with the heater hose system.

Edited May 22, 2023 by Jerry Callo

[Knoxtnhorn 6066]

Thanks for all the help.  Checking the valves in a few.  

 

[ROFL BOX 6649]

NecroBump:

Looking for an Austin area repair shop that specializes in AC work & I don't mean the compressor.

The dash is already cracked (badly) & the "blend door" stuff behind the glove box that controls the hot // cold mix is apparently my primary issue (including an occasional sort of "buzzing" or hum from the fan).

If I'm gonna replace the dash (stupid expendive) & an AC specialist will have to go down through the top, I should probably have the AC fixed @ the same time.

The closer to Dripping Springs (or South Austin) the better, however I would probably go as far as New Braunfels or Round Rock for the right shop.

[Jkwellborn 6749]

You sure it’s the blend door itself and not the actuator that moves it? You don’t need an AC shop for that. Have your mechanic do it. The actuators are easy to change on some vehicles. The blend door is more of a pain. I’ve got a broken one on my 97 and I’m not paying to have the dash pulled apart.

[Gil Bang 26049]

2 hours ago, Jkwellborn said:

You sure it’s the blend door itself and not the actuator that moves it? You don’t need an AC shop for that. Have your mechanic do it. The actuators are easy to change on some vehicles. The blend door is more of a pain. I’ve got a broken one on my 97 and I’m not paying to have the dash pulled apart.

It's more likely a vacuum leak.  The actuators are vacuum controlled, and the plastic hoses tend to crack. 

[Jkwellborn 6749]

It's more likely a vacuum leak.  The actuators are vacuum controlled, and the plastic hoses tend to crack. 

Pretty sure it’s vehicle dependent. My 97 has a rod that connects it. There isn’t a vacuum hose going to it. There are two on the truck so I guess it’s possible.