Preparing A/C lines to be used

Jeff Lange

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I've had an A/C setup sitting for years, with the lines exposed to air. What should I be using to flush/clean them so they can safely be used? Should I replace the expansion valve?

Okay, here's the current plan, I'm not too experienced with A/C, but I do know some stuff and have read extensively, just looking for some other opinions. All A/C components have been exposed to atmosphere for approximately 3 years.

Clean/flush all lines, condenser and evaporator.
"Overhaul" the A/C compressor (install all new seals/o-rings, set clutch depth).
Fill A/C compressor with correct amount of ND-OIL 9.
Replace all o-rings in system with R134a o-rings.
Install R134a fittings to high/low side lines.
Install new R134a retrofit receiver/drier.
Charge with appropriate amount of R134a.


Is there anything I am missing here? Should I be replacing more parts?

Jeff
 

HommerSimpson

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Myself i would just blow threw them with air and make sure they are not pluged with a muddobber or dirt or something... yes replace exp valve and dryer... then you need to have it it put on a vacume machine for half hr or more... You can just shoot carb cleaner down them and then wash out with a garden hose then blow dry with air... its the vacuming down for half hr that will remove any mosture left in them...

you can get a can of a/c flush to.. its not alot of money..
Most importaint thing is having it vacumed down... seen lota guys just dump freon in cars and not vacume down and wonder why it dont blow real cold..
 

chrgd89

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yeah, you have to run some a/c system flush. you have to replace the dryer and expantion block that is a pain in the ass to get to. replace all the orings and gaskets. you have to use PAG oil if you converting it to 134a. you have to pull a vacume for a few hours. Turn the vacume off and let it sit with the gauges on to see if you have any leaks. I let mine sit overnight.
 

Jeff Lange

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ND-OIL 9 is the R134a PAG oil used to replace ND-OIL 7 in R12 systems.

I will be pulling a vacuum for at least an hour on the system.

After doing a quick Google search for "A/C System Flush" I seem to have found more information than I had found before when searching.

Thanks!

Jeff
 

HommerSimpson

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Jeff Lange;1387001 said:
ND-OIL 9 is the R134a PAG oil used to replace ND-OIL 7 in R12 systems.

I will be pulling a vacuum for at least an hour on the system.

After doing a quick Google search for "A/C System Flush" I seem to have found more information than I had found before when searching.

Thanks!

Jeff

proper way to flush is use a/c flush and dry nitorgen... but not everyone has tank of nitrogen laying around....
 

Jeff Lange

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Follow up question:

I've taken one apart before, and put it back together, so I know how to do it; however has anyone ever seen any instructions or diagrams for performing the overhaul using the Toyota kit on a Denso TV14 A/C compressor?

Just curious.

Jeff
 

Jeff Lange

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One thing I've noticed is that some of the information posted there regarding oil usage, etc is in direct contradiction to what Toyota says about retrofitting to R134a. A lot of it doesn't apply to me, as I will have a fresh system that never had R12 in it (effectively), but all Toyota retrofits use PAG oil, and I've never seen one come back with problems, but they consistently say that the use of PAG oil in a system that used R12 is cause for catastrophic failure.

Is it simply due to the type of PAG oil Toyota uses in the retrofit, or is there more to this?

I am going to be using ND-OIL 9, which is what Toyota says is to be used with Denso TV12 and TV14 compressors running R134a, so I'm not really concerned with it for my application, but has anyone run across this before?

Jeff