Hi everyone..I am following Rocos magic AC write up to swap out my compressor (leaky control valve) and accumulator/orifice tube.
Anyway I got the system broken down and components off. Then I taped up all the openings whilst I inspect everything before putting back.together.
Got a new compressor, accumulator and orifice from Rocks so all good there.
But when I pulled the orifice there were a few aluminium sand grain sized shards on the screen and some dirt but only what you can see in the picture and nothing on the other side round the back of the screen...is this bad or normal wear and tear.. 2001 Z06 with 56000 miles
Also I have 1.6 oz of oil in the old accumulator shall I replace with 2.0oz in the new one as per Roccos instructions?
My main worry is the dirt on the orifice or shall I just put it back together with the new parts? I don't really want to flush out if un necessary
Please give me some advice guys

 

I just went through this. My a/c died 6 months ago. The compressor would not create any differential pressure - both the low side and high side were the same. I checked the pressure sensor and the magnetic clutch, both were ok.

It took me 6 days. I replaced the compressor, condenser, accumulator and orifice filter. I flushed the 3 metal pipes and the evaporator. Something was plugging up the evaporator as it took several tries flush it. All of a sudden, a bunch of gunk came out. Then I ran dry air through for several minutes. What ever you do, don't skip this step. Or you will be doing the job all over again.

Another surprise was the o-rings. The ones that came with the accumulator and condenser were the wrong size. I found this out by pressurizing the a/c system to 125 psi using nitrogen. I could hear hissing. Used some kids blowing bubble stuff to locate the leaks. I bought the parts from a gm distributor - all the correct oem parts. Ended up using some older o-rings from a o-ring kit that had the exact same size as the original o-rings.

Then I ran a vacuum pump for several hours with a micron gauge attached. Got it down to 750 microns and then added a can of r134a (while the pump was running). If I cut off the a/c gauge and stopped the vacuum pump, the micron gauge would climb. I had a small leak in the low pressure connector (to the gauge). Anyway, I got around that by breaking the vacuum with the r134a.

With regard to the oil, I put 2.5 oz in the compressor, 2 oz in the condenser, 2 oz in the accumulator and 1 oz in the evaporator (using a small plastic hose). Then buy a pressurized pag-46 oil (2 oz) and slowly add that when the a/c is running on the low side. Close enough...

Got it all put back together and have been using the a/c for 3 days. It is fantastic to have a/c again. But this was one of the toughest jobs I've done....

 

pjensen is spot on. Flush, Flush, Flush. When you think that you got it all, flush it two more times. Any metal in the system will at least hurt performance, and at worst cost you another compressor.

 

I hear you about the orings for the accumulator and thanks for the input ! The ones that came with the new item looked too thin to me unlike the black ones that came off the original accumalator. Luckily I have a universal o ring set and there are green ones in there that are identical to the originals..
As for flushing the system I literally have like 10 tiny pieces of metal on the orifice screen..is it really gonna hurt not to flush..I am changing out the compressor anyway so if it is dieing it can do so in the bin. That dust could even have come off the assembly line maybe..?? Could someone chime in and give us some more ideas please ??

 

Yes it will hurt not to flush. My orifice filter was clean - no debris at all. Yet there was some crap stuck in the evaporator. I think this is what killed the compressor. Maybe the accumulator desiccant came out and plugged up the evaporator.

You really won't know until you flush it. You could kill the new compressor instantly.

Look at the warranty for the compressor. You have to have a receipt showing you bought the flush, a new accumulator, orifice filter and condenser. If you flush it, you won't need to use the warranty....

 

Fare play... Must be my age but I forgot to mention that I had no AC issues prior to pulling it all apart bar a pesky AC control valve leak. It was blowing 39F albeit a little low on gas. But me being me I wanted to fix the leak and that's where we are. My new compressor has a screen on the inlet but I really appreciate the guarantee issue and six days work for you...wow I am on day 2 already.
How about a blow through with nitrogen.. I can get that stuff and fit myself a new condenser ???

 

My garage is not air conditioned, so it is around 90 degrees. I would put in a few hours and rest a while. Many times, I would get stumped and go back and reread Roccos instructions. Then read dozens of threads trying to figure out the problem.

One was how to put the dual metal tubes back in place. No matter what I did, it would not go back in. Finally figured out that the compressor had to be removed (again) and then the tubes were slid in from the front. That cost a half day.

Another was the o-ring leak problem. That cost a day or more. Then I had a leak in my gauge r134a connector. Swapped out to an older connector that worked better.

There were other problems like not having the right tools. Went out several times to harbor freight and northern tool.

Yes you could use nitrogen but I doubt it will take out the oil or the little bits. I had bought the flush kit from tooltopia and the flush from napa. It wasn't expensive. I was done in 30 minutes once I got the air compressor hooked up to the metal bottle. Frankly I was shocked how fast it blew out the crap. I went through the whole quart of flush. Just give it short blasts, a second or two.

If I had to do it again, I probably could do it in 2 to 3 days easy.

 

 

Thanks for all the valuable input! I have just finished stripping everything including the condenser. My plan is now that I only have to worry about the orifice tubing and the dual metal compressor hose to clean. Everything apart from that will be replaced. The only other pesky thing is the evaporator...did you flush that too? I have heard horror stories about not being able to get the solvent out.
When I looked at the suction screen on the compressor it was clear apart from a tiny particle of plastic that I could hardly see and the screened port is sucking from the evaporator so not sure if I will clean it or not..what do you think?
And there was oil in those lines I took off so how did you figure in how much you loose from them when pulling it apart. My new compressor says its filled with oil but not what weight it is so not sure if its pag 150 or 46..do they mix?
Sorry to bombard you with questions but I want to join the "did it myself" club !

 

Yes I flushed the evaporator. It was interesting.

At first nothing happened when jamming the flush nozzle into the evaporator tube and squeezing the trigger. Then I tried the other evaporator tube.- nothing. Kept trying with short blasts. Then wham - a bunch of flush came spewing out the opposite tube.

I had checked the compressor by spinning the shaft. It actually had suction on the intake. I could not feel any pressure on the outlet port when spinning the shaft. The oil was clean of debris - a clear green color. There was 2 oz in it. The accumulator had no oil at all. Probably broke up inside.

I blew regular compressor air through the evaporator and the metal tubes using the empty flush gun. I put a drier on the air compressor outlet. I noticed before I did that, there was a brown water that was coming out the air hose. That was another trip to the store...

I used the pag-46 oil. GM changed over to that oil in 2006 (from memory). The old oil is pag-150. Do they mix? I don't know. That is the best reason to flush....

My compressor was from GM and had no oil. So it was easy - there was no oil in the condenser, accumulator, evaporator, compressor or the metal tubes. I looked at my gm manual for the numbers,

 

Sounds like your evaporator really needed a blast ! I am still thinking on the evaporator flush but deffo the tubing . all the oil I have taken out so far is clear green like washing up liquid..lol But now I am stumped with what oil is in the compressor! I need to put up another post to see if anyone has had an AC Delco compresser from Rocks and what oil is in it.. you are right this just goes on and on!!