94 A/C Ready to Purchase

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dave s

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Just use compressor oil on the seals.
Thank you! I got too busy to search that up today. My lines were delivered today so I'm all set now! I'll try to document this as I go along. Thanks for all the help everyone.
 

R422b

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I debated on getting one for my 95 when I replaced mine but I opted not to. I know in the world of refrigeration that I work in they work great till the system runs out of refrigerant while they are turning. After that you have to replace them or at least that's what I've been told. Ive had a few systems that where ran without and where ok but I wouldn't want to chance it. That right there is what turned me away. In theory your system shouldn't ever run out but we all know it happens.
That is a totally non automotive reason. In a hermetic scroll the tolerances are quite tight and if there is no refrigerant insulating the electrical connections internally or even worse if the leak allows moisture to get in to the system there is not much to keep it from shorting out and killing it.
I love scroll compressors but I have no idea if automotive ones are any good.

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smdk2500

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That is a totally non automotive reason. In a hermetic scroll the tolerances are quite tight and if there is no refrigerant insulating the electrical connections internally or even worse if the leak allows moisture to get in to the system there is not much to keep it from shorting out and killing it.
I love scroll compressors but I have no idea if automotive ones are any good.

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I agree with it being a non automotive reason but that is the only thing i have delt with. So that is all I have to base my opinion on.
 

dave s

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Well yesterday I finally got started on my A/C replacement. I took pics but my company phone security crap won't let pics go through for a day unless it's to a company recipient. I was able to Air Drop them to my wife though who emailed them to my personal account so now I can add the pics.

You would think after having the grill out multiple times I would remember to pop the tabs and slide it right out. Old age has a way of adding obstacles to any job some days. So I'm half way through removing the tiny bolts on the little valance pan under the grille before I remember to just release those tabs....holy crap. I felt really dumb. So I took it off anyways just to give it a good cleaning, possibly repaint as it's pretty beat up in a spot.

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One line on the condenser came right off, the one with the orifice tube started off but got tighter and tighter until it stopped.
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Got the Milwaukee cutoff out, couple seconds and good to go.



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Now I'm really sweating the connections at the filter/dryer. Both came right off!



Next was the lower connection back in next to the motor and heater box. Took the dryer bracket loose and was able to get my wrench on the nut finally. I worked at it awhile cause that wire bundle is right in the way. Finally it broke loose ripping my knuckle on a bolt somewhere in that mess. But it was off!


Next I unbolted the compressor. I was stumped for a bit until I noticed the bolts had a flat spot to give you clearance to slide over the pulley. Took the top ones out but never could get the bottom one to come past the pulley. So I put a grinding wheel on the Milwaukee and made a flat spot on the old pulley on the compressor and it finally came out.


Took out the snap ring and the switch(high pressure ?) and that compressor was dry! Still turned but zero oil.

I could also see in the bracket all the old oil residue from it leaking. I didn't notice that until it was out. Then I cleaned up the switch and put it in the new compressor. The new compressor says it comes with 5.3 oz of pag 46 oil in it. I read it takes 8 ounces for these trucks so I need to add 2.7 ounces to this system. Where is the best place to add this oil? Condenser? Evaporator? Line?

That's as far as I got last night. Going out later and press on. Hopefully my pics come through. I'll add them then.

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smdk2500

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I would put the remainder of the oil in the dryer. I know how you feel about the taking the grill out. Every time I take mine out I do the same thing. Get pissed because it wont come out then remember to lift the tabs.
 

RichLo

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Awesome! I'm glad you got it working on your own!

Do you have a list of parts and tools that you needed to complete it start to finish?

Also for future posts, please break apart large posts into smaller paragraphs... those super long ones are hard to read through.
 

dave s

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Next you can see the lower hose connection which was probably the hardest one to access. It was the knuckle buster.

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Next I flushed out the evaporator. I had filled the reservoir on the flush gun and filled the evaporator from the bottom slowly and as soon as it dribbled out the top line, I stopped and let it sit for awhile to soak anything loose. Then I moved it up top in this photo and ran the last little bit of flush through followed by a half hour or so of clean dry air from my compressor.

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This is the flush gun I guess you call it. Spin the silver can off and fill with flush, spin it back on, connect air and slowly turn it on. Be careful because it empties really fast.

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This is the kit I bought off Rock Auto.
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New condenser has an extra connector my old one didn't have. Never did a thing to it, it's just capped still.

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dave s

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You can see where the oil had all leaked out of the old compressor. It looked clean until I pulled it out.

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I monkeyed around for awhile trying to get these bolts out until I got a light out and saw the flat spot that would let it clear the pulley and then remove the compressor. Pretty clever of them. Just before I got the light I was lettin all those idiot engineers who designed this setup a good reamin out but I soon calmed down once I found this.

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Switch came right out. I cleaned it up and installed it into the new compressor.

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New compressor.
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Old compressor bone dry but not locked up yet.

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