A/C question for my 2006 Dodge

[bigbadchev84]

I have a 2006 dodge 1ton 5.9 cummins 110k miles. The A/C compressor coil went out in it. I have verified it is the coil- it does nothing with power jumpered to the coil. I was doing some reading and it looks like the compressors/coils are crap and they recomend replacing the whole compressor instead of just the coil/clutch assembly.

I have a buddy with a vacuume pump/gauges/refrigerant, But want to replace the compressor myself. I have read a ton on replacements, but came up with a ton of different info.

I was wondering if I can just unbolt the old compressor and bolt in a new one. The compressor didnt grenade or anything so there will be no "trash" in the system. Do I need to add oil as well? how much and what is it called?

 

[Fordum]

Check to see if the new compressor has oil in it already. Some do and some don't. Make sure you replace all O rings with AC type O rings.
If you are not sure about the amount of oil, try pouring out the old oil out of the old compressor and measure it.
Don't reuse it, put in fresh.

Don't replace the compressor without pulling a vacuum on the system afterwards. Many times you can get away with not doing it, but the one time you don't, can cost you dearly.
You should be using a service manifold to work on it. Hook the vacuum pump up to the main line and hook up the high and low sides.
Turn the pump on, and open both valves.
After you have pulled a good vacuum on the system, close the valves and wait to see if it holds.
If it does, when you are ready to put in the gas, hook the bottle to the main line of the manifold.
Loosen the other end of the hose slightly, and crack the valve on the gas bottle. Let the gas push all the air out of the main hose, and then tighten it.

Then, when you start charging, there will be no air getting into the system.

Personally, I would never change a compressor, even on a good system, without changing the filter/dryer, and the orifice tube.

There are wear particles that will build up in a system and can clog the orifice tube. Plus the "sock" in the filter/dryer can fail and let the dryer stuff fill the system.
Of course, that is on a system that has been running for a time. A couple of times I have replaced all that, only to have something else go bad fairly quickly.

In those cases, I would usually just pull a vacuum and let it go.

Any fitting you break loose, needs a new O ring. Much cheaper than Freon...........

 

[KirsL]

What J says is good advice but I'll add this. Any time time you have to open a refrigerant system you change the dryer. The material the dryer contains will absorb the moisture from the air, you can get away with reusing the old one but the a/c will not work 100%. It's a cheap enough part to just change it out. Think of it like the oil filter on your engine, you change that when you change the oil don't you. Same thing applies here.

Also before pulling a vacuum on the system, I'd recommend you pressure test it preferably with 100% nitrogen. CO2 can be used but it can actually introduce more moisture into the system. Reason is two fold, one you can find if there are any leaks in the system before pulling a vacuum or filling with freon. Two because nitrogen doesn't hold much if any moisture when you release it you remove a fair amount of any moisture that built up in the system while it was apart. Which makes the vacuum pumps job that much easier. You'll need a micron gauge too. It measure how much moisture is in the system when you're pulling a vacuum. If you're able to pull it down to around 250 microns you're good to fill the system, but if the pump isn't able to pull the micron level down any, even if it pulls a vacuum, you have a leak somewhere letting moisture into the system.

Seems like a lot of extra work but it's the right way to do it and have it work correctly.