I was surprised (shocked) too in seeing what was available for DIY's.
Loan a tool vac pumps and gage sets, the refrigerants, oils, and all the parts at local national chain stores.
I had no idea all that was available.
Kind of scared to think how dangerous I just might be if I were to take advantage of that stuff.

 

Get yourself a complete shop manual, and you'll be able to do it with the help of that. Straight forward mounting and refilling an HVAC isn't difficult, the tricky parts is if something out of the ordinary happens and you need to understand the pressures and troubleshoot it. Another thing that is something of an art is to properly tune a system, but it's not really necessary in a vehicle.

 

Sorry for the late response, I just saw this and wish I had seen it sooner. Not sure if you're still trying to get this whole A/C situation fixed but I just went through replacing a bunch of A/C components (compressor, condenser, accumulator/drier, expansion valves, o-rings) in effort to get A/C blowing ice cold again like I can only assume it once did.

First question is, at any point of installing the compressor and the compressor clutch being engaged, did you not have the proper amount of PAG oil in the system? Some compressors come pre-filled (usually with an unknown amount of PAG oil), others are shipped dry. If you installed a dry one and never added PAG oil this would be why the compressor clutch is seizing. The pulley on the compressor itself will always turns freely unless a bearing is bad, but the clutch is what relies on PAG oil for lubrication when rotating. And without the proper amount of PAG oil (14 oz in your vehicle), you'll never get an optimal charge, resulting in optimal cooling temperatures.

So on to the next topic: expansion valves. If they are clogged, there's probably debris elsewhere in your system. Especially if you first compressor burnt out. This means you really need to do an A/C system flush. You can do this yourself, but you'll need a big air compressor and a moisture filter, and you'll also need to remove both expansion valves to flush out the lines and the evaporators. It's a very tedious job for a DIY'er like you and I, and you don't want to end up with flush agent trapped anywhere in the system because it will eat up your new PAG oil and cause your compressor clutch to seize once again. I highly recommend taking the car to a trustworthy shop to do this. I know it's tempting to just try to do it yourself, but trust me, without having the fittings to adapt an air hose directly to your A/C lines and let the air run at 80 or so PSI for 30+ minutes per line.... you're not going to want to do this yourself. You also need to have your compressor, condenser, and accumulator removed for this procedure.

After flushing the system you'll want to install the new expansion valves and o-rings, and connect the lines back up.

Once you get the compressor rebuilt or replaced (again) I would start with draining the PAG oil from the compressor before installing it and hooking things back up. Start fresh. If you put oil in the compressor before installing it you risk tipping the compressor and losing and unknown amount of oil, which means you won't know how much to add back to make sure you'll end up at 14 oz total.

After getting the compressor installed, I'd fill the compressor with the PAG oil via the high pressure line (the smaller diameter line) coming off the manifold that bolts to the compressor. You're going to need a pretty small funnel that will fit into the high side line o-ring connection, and let gravity take care of the oil getting to the compressor. Adding the oil anywhere else (ie: high side pressure port, low side pressure port, etc.) will allow oil to rest in the higher-sitting lines, and the vacuum pump will remove an unknown amount of oil, despite what others may tell you. After getting 14 oz of oil (I suggest adding leak detector with the oil, by the way, in case you have a future leak) but the rest of the lines back up and do an extended vacuum.

If using a small vacuum pump (less than 3 cfm) I'd let the pump run overnight and vacuum every last bit of moisture out of the system. You'll need to hook up an automotive A/C gauge set to the pump so you can draw vacuum on both the high and low lines. I'd draw vacuum down to -29 Hg (inches of mercury), however many minutes that takes, and then turn off the pump. Leave everything connected and let the system sit for an hour or so and make sure the needle on the gauges doesn't move. If the low pressure gauge drops to a lesser vacuum (or to 0 PSI), you have a leak. If you don't have a leak, kick them pump back on and now perform your extended vacuum to draw all moisture out. Have plenty of extra pump oil on hand in case you start pulling too much moisture and need to re-fill the pump with fresh oil once or twice.

After the deep vacuum, assuming you're not using one large 30 lb tank of R134A and a scale, shut off the valves at your low and high pressure ports, remove the gauge lines, and purge the short line on your recharge cans and start filling. You'll need 58 oz of R134A, and make sure you're not using any cans that say that they seal leaks. Even most that don't advertise leak sealer on them still contain leak sealer. Make sure you get cans that don't contain leak sealer.... they gum things up (ie: your new expansion valves).

https://www.amazon.com/DuPont-R134a-...4a+refrigerant

^I recommend that. No leak sealer, very good quality refrigerant, and far less than you'll spend at your local parts store. You'll need almost 5 (4.83) cans worth to get 58 ounces into your system, and you'll have one fill can left over.

With the engine running and the A/C turned on (put it on the coldest setting, fans on full blast on the front and rear units), once the system reaches enough pressure from the cans, you're pressure switches will allow the A/C compressor clutch to kick on and start putting out cold air. You MAY need to jumper your compressor relay at some point if it does not come on on its own after adding some refrigerant, and if the system stops taking refrigerant because the clutch isn't running.

Ideally, vent temps should be around 40 degrees (colder is even better!) and as long as your low pressure gauge on your recharge can is where it should be based on ambient temperature, you're good to close up the can, disconnect the recharge line from your low pressure port, and hopefully enjoy your A/C for much longer than 5 months.

 

Now, you'll see this is a bit of a task. Might be more tempting to spend $200-250 to let a shop do the following: perform the flush then take your car back home and install the new expansion valves and install the compressor, add the oil, and reconnect the rest of the stuff. Bring the car back to them and do the vacuum for you and the recharge. Though they probably won't vacuum the system for as long as you'd like, so you may want to rent a vacuum pump from AutoZone or Advance Auto and do the vacuum part yourself.

Adding the proper amount of refrigerant is critical, and if you get air in the system between changing out several small cans of R134A you're not going to be doing yourself any good. They use the large tanks to do the recharges, and only have to purge the charge line once, where as you'll have to do purge the line on your refill bottle after every can.

If you have debris in your system, you really should be changing your condenser too. The tiny passage ways get clogged and inhibit the performance of your A/C system. You absolutely should be replacing your accumulator/drier, no questions asked. Anything you replace, install it AFTER the system has been flushed.

It adds up to a good bit of money in parts alone, but you're risking paying for everything twice if you leave debris-filled A/C components in your truck, and your system won't perform like it should. Check Amazon and Ebay though for expansion valves, condensers, and accumulators. Sometimes you can buy an entire kit of all of these items or a combination of these items, that will also include o-rings, which you'll also want to replace everywhere possible. The o-rings are cheap insurance.

Hope that helps, and if you have any other questions shoot me an e-mail at agrayson84@gmail.com and I'll do my best to help you out, as I don't always spend time on the forum here.

 

Just checked back in here since I have not been working on this lately.
With winter setting in here in Michigan, it has not been a priority right now.
APPRECIATE the detailed info !!!
I am thinking that I may try to pull this apart again towards spring, seeing if I can identify anything causing blockage or seeing if I find anything as far as debris.
Then planning to seek a pro's help.
Just one question I guess at this point.
The vacuum pump won't draw the oil out of the system?

THANKS again !!

 

No problem. Check paragraphs 5, 6, and 7 in my first post to get your answer. If you drain any oil from the new compressor, remove expansion valves and flush the lines properly, and fill it the way I mentioned, you won't lose any PAG oil. Even a 6 CFM pump like I have won't be able to pull oil from the compressor nor accumulator/drier after running for a few hours. However, if you don't flush your lines first, or you add PAG oil into one of your service ports, you risk oil just sitting in level areas of the lines instead of all of it making its way down to the compressor and/or accumulator. Any of the oil resting in those lines that aren't far from the service ports will surely suck right up with a decent pump, or even a cheaper pump if you let it sit on long enough to remove all moisture and air.

Doing it the way I mentioned is definitely not the most convenient. It's time0consuming to be honest, but it's a sure-fire way to make sure you have the exact amount of PAG oil in your system. Otherwise you risk leaving existing oil in the system, and/or losing oil during a vacuum.