[A_White]

I was trying to charge up my AC with a wal-mart can of r-134a with the gauge on it. When I hook up the gauge with the truck running I can here the ac compressor click in and out about ever 5 seconds. The gauge goes from low to overfull when it clicks over. The ac was only working on MAX AC last summer and now it doesnt blow cold at all. I was afraid to put any r-134a in it because it goes from low to overcharged.

Any Ideas? Maybe an ac relay? Should I just add some r-134a anyway?

 

[dieseldude5.9]

yes you should charge it with R-134a, frequent A/C cycling usually indicates a low charge.

 

[39569]

And you can't overcharge it. Make sure the gauge reads around 35 to 45 inch pounds which should be the spec. any more than that then you should get another can.

 

[A_White]

Thanks for the quick response, I'm glad I don't have to change the compressor or relay. I'll go and charge it up now.

Thanks again!

 

[Mopar1973Man]

You can do the simple thing is drain the system down to ZERO pressure. Then add (2) 12 ounce cans of Freon and 1 can of compressor oil to the system and you done...

The system only holds 28.8 ounces of Freon charge...

Here is my write up on it...
Untitled 1

Amount of freon you need (28.8 Ounces converted).

Blue zone is charged!

Only need 2 cans...

And you can't overcharge it. Make sure the gauge reads around 35 to 45 inch pounds which should be the spec. any more than that then you should get another can.

Trust me you can overcharge it...:thud:

 

[SmokinTheHippies]

I tried doing one of those cans with the gauges on top. went thru the whole can didnt make a dent. i ended up just paying a shop the $150 to fill it. scary thing is he said he had to dump in almost 3 lbs of coolant, even tho the sticker shows 1.875 as the max. but its running fine and running cold so i'm happy.

 

[SmokingFords]

I went to fill mine up and the gauge said 200psi

 

[Mopar1973Man]

I went to fill mine up and the gauge said 200psi

Was the compressor even running??? :thud:

 

[SmokingFords]

It hits 200psi either when It kicks on or off then back to 25psi or so

 

[speedntriple]

And you can't overcharge it.

yeah ya can.

 

[SmokingFords]

What will happen if I over charge it

 

[elephantrider]

the vents will start throwing snowballs at you.

 

[jj53913]

It hits 200psi either when It kicks on or off then back to 25psi or so

Mine does the same how do you know what the psi is when it does that? Mine also cycles every 5 seconds also.

 

[SmokingFords]

Mine does the same how do you know what the psi is when it does that? Mine also cycles every 5 seconds also.

The recharge thing has a gauge on it

 

[SmokingFords]

the vents will start throwing snowballs at you.

My girlfriend would like that

 

[Mopar1973Man]

If the compressor is cycling then the the pressure is low. When properly charged the compressor should just stay on...

Unless...

I've seen some people make a mistake and buy freon with oil in it. The over charge the system with too much oil. What happen is the same thing... It cycles on and off. You might notice the belts squeal or oil squirting from the back of the compressor.

At this point you NEED to dump the entire system. I would opened the line at the condenser on the front and vented the entire system out. But this will allow for the excess compressor oil to leave the system. Then recharge the system it should only hold 3 - 12 ounce cans roughly when done...

Don't ask how I know this...:w::thud:

NORMAL PRESSURES, BUT A/C PERFORMANCE TEST AIR TEMPERATURES AT CENTER PANEL OUTLET ARE TOO HIGH

1. Excessive oil in refrigerant system.

1. (Refer to Plumbing/Refrigerant Oil/Standard Procedure - Refrigerant Oil Level) in this group. Recover the refrigerant from the refrigerant system and inspect the refrigerant oil content. Restore the refrigerant oil to the proper level, if required.

 

[SmokingFords]

I have been buying the wrong stuff

 

[Mopar1973Man]

I have been buying the wrong stuff

This is what you need... (No PAG oil included...) Typically 12 ounce cans... If it bigger then I bet you money its got oil in it...

Here the sticker on the front by the radiator...

Normally the only time your suppose to add oil to the system is if its been completely empty because of service. Like removal of the evaporator in the cab etc...

 

[andrewpursley]

ur truck holds 2 pounds of freon and about 8 oz of pag 100
if completely loss of charge u have to vacuum the system down to remove ambient air and moisture but dont add all 8 oz of oil if all oil isnt removed even if no freon still has oil in system mostly in compressor and acculator too much oil wont cool and too little will kill ur compressor

 

[youngcummins08]

you need to get a double gauge kit that has a high and low gauge. My low was 65ish psi. You cant drain the system and just fill it back up. You have to vacume out the system. If it is too full take to a shop. We use a 30lbs tank to fill our cars up and the customers cars at the shop. The same exact thing the dealer and shops use.