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Changing out the compressor, Accumulator and Orifice Tube...

3K views 15 replies 7 participants last post by  castlerox 
#1 ·
Okay folks, I am getting ready to do this!

The Compressor has arrived. Still waiting on the Orifice Tube, Accumulator and r134. I have the shroud, grill off and am surveying the task at hand. I had a few question before I go tugging around and create a big fat mess.

The system has been evacuated.

The compressor seems pretty straight forward as far as I can tell. I am assuming the oil in it is A OK?

Accumulator:

On the picture below, I have a few questions. Are the arrow directions on the upper right the correct directions to crack those nuts?
the purple circle… just unclip and unscrew the black bolt?
the green circle… do I just crank the black nut? It looks like 2 actually…


Orifice:
Is this where it is? Do I just crank that brews bolt?


Thanks in advance… I am hellah nervous. Should I grab anything from the LAPS in advance?
 
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#3 ·
I'd buy some PAG150 to replace any that comes in the compressor or that may need to be added to it. Also need a graduated cylinder. Don't forget to factor in any oil that comes in the R134A cans if you purchased ones that come with it. Gonna be easy as pie, you'll see. Like a chemistry experiment.
 
#4 ·
Yes to all of the above questions and answers.

The nuts and all are as you expect.

I too would try and "replace" any oil in the compressor. You can't get it all out, of course. But you're really not sure how much is in there. Some guy might have turned the thing upside down in handling and drained some out etc.

Some report trouble getting the orifice tube out. I didn't have any trouble. It's usually marked with an arrow for refrig flow. That's DOWN. But to be safe, when you pull your old one out, note which way it points (short side, long side).

As I have mentioned before, I recommend against the variable style orifice, as my friend the Scottsdale city mechanic does. I took mine out when it gave me pressure problems. Replaced it with the $5 non-variable style.

When it comes to filling the system...I recommend very early in the morning for where we live. The gauges usually are marked for temperature but it gets a little whacky, I think, when the ambient temp is 90 deg. Easier, and perhaps more accurate, to just do it when it's 70 degrees. I filled mine till the compressor just barely stopped cycling plus a smidge more. Didn't really go by the gauges much. I tried the gauge thing the first time. The low and high would never really reach their expected levels. Either the low was way off or the high was way off. But the "fill till compressor runs" method (my 2nd time) worked great.

Have a paper clip and/or jumper wire available. When you're filling, you can unplug that electrical connector on the rear of the accumulator, jumper the two contacts and the compressor will run. If you're running in refrigerant and it doesn't seem to be going any where, jumper that connection for a few seconds and the compressor will pull it into the system.

Wear safety glasses, freeze proof gloves and a condom.

Ambient temp in Phoenix... :rofl: :rofl: :rofl:

Lump
 
#5 ·
castlerox said:
Thanks in advance… I am hellah nervous. Should I grab anything from the LAPS in advance?
Get a complete o-ring kit for the van; they're only about $5. As long as the system is open replace every possible o-ring. Get a bottle of pag150 oil.

Like Cargo says get a graduated cylinder for oil. I got one something like the one pictured for about $5 at walmart, good enough. Just about any kitchen department will have something similar.

Rule of thumb for refrigerant oil; drain the oil from the old accumulator into you graduated glass, then add that amount of fresh oil to the new accumulator. Same with the compressor. The new compressor probably came with oil and its probably too much. Drain it and add correct amount. I think it's typically 3-4 oz in the accumulator and 4 in the compressor for a non-rear air system.

crate-and-barrel-glass-mini-5-0z.-measuring-cup.jpg


I have a fresh accumulator and orifice tube sitting here in a box just in from Rockauto, I'll probably be doing the job this weekend. It's been 6 years since I overhauled mine and the high/low pressures are out of spec and the temp is not as cold. I expect to find a slightly clogged orifice.

Good luck with your project!
 
#6 ·
Yup, I added too much oil to mine by accident. Pressure spiked into the 450 range and then blew oil out of the compressor O rings...made a mess. Now, the pressure rises to 250 and then back into the 150 range ( high side ) and my low side is where it is supposed to be. I thought I had added too much refrigerant originally since my low side was high too, but once I did some research, realized my mistake.

Make sure you get Pag 150, not every store carries it from what I noticed when looking for it.

Don't forget to pull a good deep vacuum on the system before you charge it or you won't get very good cooling due to air/moisture in the system.
 
#7 ·
You guys are awesome.

I actually installed the compressor before getting to this thread. I installed it with the oil inside it… so I am going to have to assume about 3oz on that one.

I did end up buying PAG150, Ill use that for the accumulator.

Spending the day on this!
 
#8 ·
Ok I'va managed to get everything loose except the 2 big "double" bolts on the accumulator… I feel like I'm going to rip the thing off… Whats the trick? I guess a part of the confusing is why did they use this double nut setup rather than the coupler type found everywhere else…?

Its the green circle and the arrow ones in the accumulator diagram at the top… I just don't want to break or strip something… the end is NEAR!
 
#11 ·
OK, all the parts have arrived and are installed. Ive tightened everything up and swapped out fresh Green Orings on all the fittings. Added 4 oz of PAG150 to the Accumulator.

I would assume my next step is to vacuum the system and see if it holds?
 
#15 ·
Aright well... There is a leak.

So... To trace it, would you add a little dye to the system and find it that way? Obviously it is going to be in one or more out of three places...

Bummer!
 
#16 ·
I just want to conclude this thread and thank everyone for their help.

I ended up taking the compressor back out. After closer examination of the old one, I realized it was completely devoid of oil as was the accumulator. Makes sense since the seals of the compressor were the original problem.

I added 4oz to both the new Accumulator and Compressor. retightened everything and replaced all the Orings again.

Once everything was in I did another vacuum of the system and then added 3 1/2 cans of 134a. That total should bring me right up to about 48oz, 8oz in the compressor/Accum and 40oz from the cans.

It runs super great right now, I couldn't even tell the compressor was running it is so quiet. Blows cold front and rear.

Hopefully it holds, but it is full of dye and I think I can find a leak if one should arise ;)

Thanks again!
 
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