Hey,
I don't consider a leak being able to contaminate the system. Only a catastrophic failure such as a compresser seizure/failure would cause enough contamination to warrant flushing of the system.

The only "contamination" in there now would be moisture. I have a good Robinaire vacuum pump. Running it for a day or 2 would suck out any moisture. So to answer your question no I did not flush the system.
I am also planning on replacing the accumulator though.

Any comments on my questions on the fittings and oil?

Danny

__________________
1984 300SD Turbo Diesel 150,000 miles

OBK member #23

(\__/)
(='.'=) This is Bunny. Copy and paste bunny into your
(")_(") signature to help him gain world domination

"I don't consider a leak being able to contaminate the system."

That means you have not read the archive posts about it and that you are not reading an AC manual.... and that you don't believe me... so I can't help you under those restrictions.

Don't use locktite.

Use new, proper sized "O" rings and a product called Nylog.

The threads don't seal the A/c system; the "o"rings do.

__________________
The Golden Rule

1984 300SD (bought new, sold it in 1988, bought it back 13 yrs. later)

Thanks, I read about nylog I'll have to get some.

Sorry Lethermang. It's not that I don't believe you. I know air and moisture can possibly contaminate the oil and make it acidic. I just don't flush ac systems unless something catastrophic happens.
Maybe something catastrophic will happen now!!

Anyway I'll try to lessen my restrictions in the future!

Danny

__________________
1984 300SD Turbo Diesel 150,000 miles

OBK member #23

(\__/)
(='.'=) This is Bunny. Copy and paste bunny into your
(")_(") signature to help him gain world domination

If you will find the two longest AC threads in the diesel forum... you will find plenty of evidence that a leak constitutes a contamination of the oil which you are trying to figure out how much to have.. ( I may have posted a picture of the AC manual stating exactly the same thing )... but I do know it says that.
The trick is that it is almost impossible to get the right amount of oil except by flushing and starting at Zero... and with the length of leaking you describe you can bet your present oil is contaminated...... no way to get the bad oil out except by flushing.. once it has turned acidic from moisture there is no way to get it clean by vacuum.
So your problem is a Good/Bad situation together... When you understand that your oll needs to come out... you will be presented with an easy way to get the right amount of oil into the system.

Hey,
I hear what your saying. The problem is I don't have a flushing station and I can't afford to get it done by someone else right now.
Maybe if I just didn't spend a week skiing in Jackson Hole Wyoming I could
I also just received a letter from my job I may be out of work soon. All things considered right now I just have to take my chances. I'm going to replace the receiver/dryer and expansion valve. Add 1/2 ounce of oil if I can get my hands on some and pull a vacuum and charge it by weight.

For better or worse that's just the way it is right now. It's not that I don't believe you Leathermang on the contrary I appreciate all your help and all you have done for these forums.

Maybe I can get my business modifying xbox's up and running!

Danny

__________________
1984 300SD Turbo Diesel 150,000 miles

OBK member #23

(\__/)
(='.'=) This is Bunny. Copy and paste bunny into your
(")_(") signature to help him gain world domination

I'm a commercial HVAC and Refrigeration mechanic with 14 years service experience. I'm certified universal and auto.

First, it's OK to charge liquid. Since you are a newbie, charge liquid only into the discharge, liquid line or receiver (high side). You never want to introduce liquid into the suction side with the system running, or right before you are going to start the system. The liquid refrigerant is bad for two reasons. 1: It is not possible to compress liquid. Get liquid refrigerant into the cylinder of the compressor and you will destroy something (valves). 2: Liquid refrigerant carries the oil throughout the refrigeration (A/C) system and will wash the oil out of the compressor if introduced too quickly.

All pros charge liquid. I'll charge as much as possible into the receive, using a scale. If the system stops taking refrigerant before it is fully charged, I will slowly bleed liquid through the suction line with the system running. *I use a gage manifold and long hoses. Much of the refrigerant boils into vapor before it reaches the compressor. I have lot's of experience, and pay careful attention to the compressor while doing this. I would never try this if you are charging for the first time and lack the correct tools and experience. That said, if I had to charge vapor only, I'd never get anything done.

Do you have a way to measure the refrigerant into the system (scale)? Correct charge weight is very important. Overcharge the system and you will ruin the compressor.

Leaks and contamination. The car has a low pressure control or switch which will not allow the compressor to pull the system into a vacuum. Depending on the size and duration of the leak, you may or may not have contamination. Any air introduced into the system is bad for several reasons. Any time a system is opened or the refrigerant removed you must evacuate, and replacing the drier is highly recommended. If there is a small leak, but the car has never completely run out of refrigerant, positive pressure in the system will prevent air from entering the circuit. If the system is completely out of refrigerant, or the suction pressure drops into vacuum with a leak, you have contamination.

With R-134A however, any leak could cause problems. R-134A, and most of the newer HFC and HCFC's are blends (pretty sure about 134A being a blend, I was taught to only charge liquid for this one, and most of the newer refrigerants clearly state to only charge liquid on the bottle for this reason). A leak may cause an imbalance of the ingredients and cause the refrigerant to change characteristics. Blended refrigerants must always be charged in liquid state, or the blend ratio will change along with the characteristics of the refrigerant. If the R134A bottle says it's OK to charge vapor, ignore this paragraph I carry at least 6 different refrigerants on my van, and R-134A is the least used.

The oil used for HFC (R-134A) systems is extremely hydroscopic. Avoid any exposure to the atmosphere if possible. Any refrigerant leak will also allow the oil to leak out along with the refrigerant. If the oil is contaminated in an R-134A system, it must be replaced. Mineral oil, the oil used with R-12 is much more stable.

Converting from R-12 to R-134A is another story, and I've never done this on a car. I do not work on car A/C's unless as a favor. There are products that allow one to use a retrofit or replacement refrigerant in place of R-12 without changing the oil. I'm not sure if these are approved for cars or not. I use them all the time for old R-12 systems. The technology is getting better all the time, and the latest retrofit refrigerants are very good.

Feel free to ask any questions. There is some great info on the web, try searching DuPont R-134A or refrigerant. I've found huge amounts of data online. Always evacuate when working on refrigeration equipment. Clean (new) filter/driers are also a must.

Lukejt

You do not need a flushing station.... although I dream of having one...
You can do the job with flush out of a can and a way to blow it through your system... and then drain it from the items which you can... and flush by putting new oil in and turning the compressor a few times... and repeat that... the evaporator and the compressor and condensor are not flushed unless one has the ability to take them out of the car.. otherwise almost impossible to get the stuff out.
The expansion valve is also not flushed .. in fact the place the expansion valve is installed is where you flush forward from through your hoses.... then you install your new equipment, install the oil and you are ready for long term success... the lower you are going to be on money the more important for it to last a long time.... given that you are putting several new items on it at this time......
But sking is more important.. LOL

LOL...gotta have priorities!

Seriously this wasn't a spur of the moment trip. I was planning that trip for almost a year. I had a lot more liquid assets, or in laymans terms, CASH back then and there wasn't any way I wasn't going!

Thanks to everyone for the advice.

Danny

__________________
1984 300SD Turbo Diesel 150,000 miles

OBK member #23

(\__/)
(='.'=) This is Bunny. Copy and paste bunny into your
(")_(") signature to help him gain world domination

"Putting the oil into the high side puts the liquid UPSTREAM from the compressor. Turning the compressor a few turns by hand is simply a precaution."--Larry Bible

Larry said that backwards ..... in case anyone actually does a search of archives .. LOL

High side is downstream from the compressor...