Adding Refrigerant

[Quadcammer]

Ok folks, the cobra's a/c is blowing not ice cold air. I imagine its a little low on 134, so I'd like to add some.

I'm assuming the compressor is turning (haven't looked yet), but assuming it is, just open the low pressure port, and add refrigerant, yes (a/c on max, blower speed on max, etc)?

Now what if the compressor isn't turning? How do i force it to kick on so I can add the refrigerant?

Further, assuming refrigerant is not the problem, but rather the low pressure cycling switch, where would I find that? (pic would be useful).

Thanks guys

 

[VirtualSVT]

Let the car idle for few minutes before adding.

Assuming the compressor isn't locked up it'll suck up the 134 just fine just keep an eye on the psi in the system. The low pressure cut off switch is on the drier on the firewall.

This is the only underhood shot I could find really quick. The switch is circled in the red Circleish thing. MSPaint FTW.

 

[Quadcammer]

groovy.

thanks

 

[Quadcammer]

And just so we are clear, the low pressure port is the on the line running from the firewall right by the intake tube, yes?

 

[Un4GivN]

And just so we are clear, the low pressure port is the on the line running from the firewall right by the intake tube, yes?

The high side should be really close to the compressor.. Also, the high and low ports are different sizes so you can't fill it on the wrong side.

I will give you advise like you would normally give others on here... don't just go and add refrigerant. Be smart, buy a decent set of gauges and check your pressures. Also, refrigerant doesn't just disappear, if you're low, you have a leak somewhere. If you are in fact low, add dye to the system and charge it so you can find the leak.

 

[Quadcammer]

I appreciate the proper advice. For right now I'm going to add the 134, and I'll deal with the leak when I have more time during the fall/winter.

 

[VirtualSVT]

134 is cheap. Most of it already has UV dye in it so finding a leak is pretty easy.

 

[Brutal Metal]

I agree throw a gauge on it and shoot for 40psi!!

 

[STAMPEDE3]

Oliver, besides the ports being different sizes the lines are also.
The bigger line is the low pressure.
While I do normally use gauges I have thrown a can in without them.

Remember, low on refrigerant does NOT always mean a leak.
In a older car it is possible to get low without a leak. The 134a molecules are small enough to seep through the hoses over the years.

also if the compressor doesn't kick on pull the connector off of the pressure switch and jump it with a piece of wire or paperclip.

 

[Quadcammer]

ok, compresssor was turning, and pressure was 32psi before I added any. Added a little bit of straight 134a to about 40psi.

a/c was cool again.

Given that I only use A/C once in a blue moon, I'll probably be fine for a while. If not, I'll do a proper investigation.

Thanks guys.

 

[Brutal Metal]

If this is the first time you've had to add it in many years I think your OK Quad and yeah getting it up 8lbs to 40 will make it feel a lot colder!