Okay could I buy FOUR SEASONS Part #*26729****AC System Seal Kit; O-Ring and Gasket Seal Kit*at rockauto.
The four seasons kit is a "Air Conditioning Seal Repair Kit". I don't know what it contains, or exactly why you would want to purchase it.
From ACKits.com, P/N: 91-MT2541 is what you want
I'm replacing all ac lines, compressor,orifice tube, accumulator, and buying pag 150.
Why on earth would you be replacing the A/C lines? What lines are you specifically referring to.
The only one that typically ever needs replacing is the one that comes off the back of the compressor because it tends to but up against the upper control arm which eventually wears a slot/hole in the hose. (Do yourself a favor and wrap heater hose around it, and nylon wire tie to secure it).
Also do I need to flush the system?
Did your system work prior to you working on it? Did a compressor let go?
When you pull the orifice tube out of the lower tube, located at the battery area, take a good look at it. It will give you a clear indication if the system has contaminants in it (Typically when this happens, the filter media is black, and has some particles on it.)
If so, then YES it is necessary to flush the system. I use Acetone because it's inexpensive and evaporates quickly.
I forgot to mention that if you are mechanically inclined and will be doing the labor yourself, you can rent/borrow a vacuum pump from AutoZone. You will need a hose to go from the pump, to the low pressure fitting on the accumulator. Draw a vacuum for at least an hour, then turn off the pump to ensure the system is holding a vacuum for 10-15 minutes.
If everything is buttoned up nice an tight, you can then take it to the shop of your choice.
Check out my post to the thread here for more info: Servicing A/C Systems
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