Guys I'm needing some info ASAP

I drained the A/C system back in January to pull my engine. Now I got it back together and need to recharge the system.

I think I have determined it needs 2lb 6oz of freon.... Can someone please verify.

Also I'm changing the accumulator/drier due to the system being opened.

The real question is what type and how much PAG oil do I put in?

Thanks in advance for your help!

 

38oz 134a
7 oz pag 46
I'd suggest changing the dyer and orifice tube

 

Is it 7oz PAG even though I'm only changing the drier? I changed the orifice tube in October last year when I did the compressor

 

What I posted was for a dry system

Use the following guidelines for replacing compressor oil when changing A/C components:

Compressor.........1.4 oz
Condenser..........1.0 oz
Evaporator.........1.5 oz
Accumulator........1.0 oz
Hoses..............1.0 oz

 

I'd highly recommend changing the orifice tube again if you are going to open the system. They are super cheap and act as little filter/strainers in the system. Technically they shouldn't be filtering anything at all, but there's always a possibility some contaminants are in the system if it's opened or gotten too hot or something, so it's best to swap that out when the system is open.

Are you vacuuming the system down as well? I highly recommend getting that done if you don't have an air compressor you can use yourself to do it (and buy the 15 dollar harbor freight vacuum pump.) Not only will you be able to detect/prevent leaks and boil moisture out when it's vacuumed, it's easier to add the proper amount of refrigerant to the system. Without it vacuumed down, there is going to be some air in the system.

 

Guys thank you for the info I really appreciate it.

And yes it's going to be vaccumed down and leak tested.

 

Are you gonna do the vacuuming and refrigerant charge yourself? Reason I'm asking is that I have a similar project coming up soon. Compressor seized and I was just going to delete the AC but wife rebelled. Never worked on AC before. I bought one of those manifold gauge sets and I have an old vacuum pump that I think will work and I bought a bunch of new parts that are sitting in a box. Going to be interesting.

 

The vacuuming and refrigerant charging is actually pretty easy. Besides an electric vacuum pump or an air compressor with an air run vacuum pump, you need a set of manifold gauges (with hoses that work with either r134a or r12 connections, whichever you have on your truck.)

Once everything is assembled, just vacuum it down. It should reach around -28 to -30in of mecury depending on elevation on the gauge set.

Once it gets down to that, you can close the ports and see if the vacuum holds over the course of several hours. If it does, you should be good to recharge. I like to let the vacuum pump run a while after the charge holds just to help get out any boiled moisture.

When you charge, make sure the vacuum is still applied and attach a can of refrigerant to the middle (yellow) hose on the manifold gauges. Make sure the valves are closed before doing this. After screwing on the can, there should be a schrader valve to press to release any air in the lines. Then with the air released, you open the low pressure side valve (blue) and let the system suck in the refrigerant.

You will want the truck running with the AC on max. Some people like to jump the pressure switch on the accumulator, but you don't have to, it will just take longer to suck in the refrigerant. I usually rock the cans back and forth during charging. When you move to the next can, close the blue valve before you take off the can. Then make sure to purge the air out of the yellow hose before reopening the blue valve.

It's best to measure how much refrigerant goes into the system with a nice scale, but you can get away without that. I usually get one more can than I need, and use about 1/2 of that can for the last step in charging to accommodate lost refrigerant between swapping cans.

Edit: Oh, and I always get the cheapest refrigerants out there. You don't need the special leak sealers and dye and all that other junk. Some of it may be beneficial, but some of it actually isn't the greatest. If you system hold vacuum, you shouldn't need or want leak sealer in there. You also won't need any dye as well. Also, if it's properly charged, you shouldn't need any special additive for extra cooling. The r134a cans at walmart are like 4-6 bucks for the 12oz cans, compared to 12-15 at any parts store.

 

Max, thanks for the great explanation. Starting to warm up around here so I'll be tackling this pretty soon.

 

No problem! I noticed you said the compressor seized. If thats the case did you get a new condenser as well? Ive read they are almost impossible to flush properly (ones using r134a) and can cause issues later if not replaced. Ive also heard people not replace them and then be fine as well, but its a big risk!

I hear you about getting warm. Im glad the ac works in my truck. However my second IDM failed on me while I was out... AC doesnt work when you are getting towed in the truck.

 

When the compressor seized last fall I read up on AC problems and I bought a parts kit that I'm pretty sure includes a new condenser. I agree, not worth the risk of screwing up the new compressor.

I read your second IDM failure thread. Does seem strange that two failed in short order. Hope the third one does the trick and there's nothing else causing them to fail. Sometimes I wonder about the need for all the electronics, great when everything is working...

 

Why do you need a new condenser if the compressor seized up?

 

If a compressor seized it has probably put metal in the condenser. You will never get it cleaned out which will cause another failure. Best in my opinion to just get a new one. I am not an ac guy but I have been there done that.

 

By the way this is a post from 2016, you may want to start a new post of your own if you need help. Welcome to FTE

 

Well looky here, I was searching since I forgot the oil capacity on these systems and this thread came up haha. I think I changed my compressor back in 2010. I don't think I changed anything when I did the 7.3 swap so I suppose 14 years of use isn't too bad.

My AC compressor failed on me... didn't appear to seize up, but with the clutch engaged it does not cool and spins very loosely by hand. Haven't heard of that failure before (last time it seized it broke the belt) but I'm guessing the compressor seized internally, but the shaft connecting the clutch must have sheared or something. Anyways, the oil inside looks a little grey so that's not what I was hoping for. Good thing I bought a new compressor/condenser/accumulator and orifice tube. I better start flushing out these lines and get this up and running tonight. Despite having 4 vehicles, this is the one I need to get to work and these temperatures are reaching above 100 degrees now in Phoenix.