Joshboody

I’d love to fix my AC, but if too tough I’ll prob rip it out since it’s mainly a track car.
AC will NOT stay on after about 2sec. Worked before until I added some Freon. Quick story:

- Since purchasing car, AC has worked but recently not so well
- Added r134 can from Walmart in 110deg heat
- Worked well last summer
- Now AC light will NOT stay on past 2sec… ever
......Pushed Schrader (low pressure) but seems nothing releases
......Tried filling but without AC on seems I cannot

- Thought maybe I could have overfilled in summer and bad pressure when lower temps. But I’d think pushing Schrader you’d hear or see something release.
- Might be nothing in the system now… if that’s the case potentially my Schrader valve is the culprit since its really the only part I’ve messed with when adding Freon.

Any advice on where to start would be great!

foggy

Sounds like you have a substantial leak..
IF you leave it ON high/max Cold, and put on low pressure charge..
The compressor should eventually come on and cycle for a moment..
As it takes more freon, it will cycle ON longer and longer..
You really need to get pressure gauges on it though

Georgies

Do you have long tube headers ? My ac line got burnt threw after long tube instal. Check if the insulation looks burnt..

Joshboody

I just tried the AC on low, so I will try on max with the can hooked up.

For gauge, I have the can attachment but other than that no AC equip.

If I press the low schrader valve, I would see, hear Freon correct... should be obvious? If nothing, prob nothing in the system?

Carl Timonen

Mine would lose the charge after a few days, so I used a leak detection dye and one can of freon. When it lost the charge, I used a ultraviolet light to find that it leaked around the seal of the compressor. So it was new compressor time for me, along with the accumulator and expansion valve.

Joshboody

Bill Curlee

Submerge the NEW can in a pail of HOT water in the UP-RIGHT position. That allows only GAS to go into the GAS side of the system!!

The HOT WATER will cause the liquid in the can to vaporize and go into the system faster AND get ALL of the contents out of the can!

IF,,,,,,,,,,,,,,,,,, The system is really empty, it will take at least TWO cans to get it cycling properly and then stay on. Then some of a third can will have to be added while you monitor the pressures.. Like "foggy" stated, you really need a set of gages to see what the pressures are and get the right charge. There is a detailed specific system set up in the service manual and the chart that is needed to followed to get the pressures right. Temp, humidity and engine RPM are taken in to count.

The real correct way to service the charge is to MEASURE the charge. If it truly lost all the pressure you should change the receiver dryer, the orifice restrictor tube and VACUUM the system out and then refill it with the correct Pounds/OZs.

Joshboody

GCG

To properly do this you'll need an A/C manifold gauge set and a thermometer otherwise you are just guessing. You don't need to buy the uber expensive, super professional ones. A modest set would do.

Take a look at this post. It has detailed instructions to check/add refrigerant.

-These are the CliffsNotes:

Check your pressures against the chart below. Make sure you take your readings with:

• Engine @ 2000 rpm
• A/C in coldest setting
• Fan at maximum speed
• Both windows down
• Thermometer in center air vent

When adding refrigerant, pay attention to both pressures, otherwise you might end up with the high side sky-high trying to get the low side to the chart's value.

Let us know how it goes.

Joshboody

Thanks, I understand there's a correct way... I don't have the equip and no experience with AC. I was trying to find a simple/cheap action to basically get me through the summer. Next season hope to have trailer and don't have to worry about driving long distances in the heat.

I'm going to try a new can in hot water to see if I can get the compressor to stay on... if not I'm pulling it.

GCG

I totally understand. You can get the A/C manifold gauges loaned for free at most auto parts stores, or you could buy a set from Harbor Freight at $48 ($60 - 20% coupon) and the thermometer is just a few bucks. On the other hand, the plain/standard cans of refrigerant used with manifold gauges are cheaper than those with built-in gauge and hose.

The can of refrigerant in hot water, as suggested by Bill Curlee, sounds like a good idea. I would try to load the can using the A/C manifold gauges and if you get the compressor to stay on, just follow the rest of the procedure. The chart will give you your target pressures.

Give it a try and let us know how it goes.

Joshboody