Replacing A/C compressor & converting to R134A Questions (1 Viewer)

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I already know the compressor is shot in my 91 FJ80 and figure if I am going to replace that, I might as well convert over to R134. Below are links to the parts/tools I plan on buying for the project. I will have a shop fill it up. Will I need any other parts or are any of the below not needed? Any tips on removing the compressor or any part of this project?
A/C compressor kit: Security Check - https://www.carid.com/gpd/a-c-compressor-kit-mpn-9742398.html
A/C condensor: Security Check - https://www.carid.com/pacific-best/a-c-condenser-mpn-pc4353p.html
PAG oil + dye: Amazon productAdapter kit: Amazon productValve core removal tool: https://www.amazon.com/gp/product/B07QVF2V2R/ref=ox_sc_act_title_3

Any tips are appreciated!
 

fjc-man

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You should replace the receiver drier (filter) tank also. You could / should clean out the condenser coil and attached lines with a chemical solvent. Bare with me, this is from memory. At a dealership level service dept we had a setup that consisted of a dispenser cylinder that the solvent was poured into, then pressurized with air. Had an attached hose with a spring loaded rubber tipped nozzle to shoot the solvent through the component being flushed out. You would shoot it through the evaporator assembly as well. Your new compressor will come with PAG oil in it. Dump it out into a measuring cup and put the same amount of fresh PAG oil in the compressor, hook it all up, evacuate with a vacuum pump, put say 1.5 lbs of 134a in through the high side as a liquid ( can upside down) static,engine not running. That should be enough of a charge to get the A/C clutch to engage when you do turn the system on. Put the remaining Freon in through the low side service port as a gas (can right side up) engine running with the A/C on. You got that,right?
 
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New o-rings everywhere there is a joint.. Use Nylog Blue o-ring lubricant. BTW it's not blue, its clear.
If the compressor is shot and scattered particles all through the system, you'll want to change the expansion valve on the evaporator too.
The drier/filter should have caught all the junk, but you never know till you pull it off. Mine exploded and scattered the little desiccant balls all through the line leading to the expansion valve and filled the expansion valve too. That's why its a good idea to flush the lines with solvent, to wash out any contaminants, including the non-compatible compressor oil.
If you are changing all the o-rings and the other components, there is no need to use the PAG with dye. The dye is actually a contaminant and is not needed.

Change all the Schrader valves too.
 
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You should replace the receiver drier (filter) tank also. You could / should clean out the condenser coil and attached lines with a chemical solvent. Bare with me, this is from memory. At a dealership level service dept we had a setup that consisted of a dispenser cylinder that the solvent was poured into, then pressurized with air. Had an attached hose with a spring loaded rubber tipped nozzle to shoot the solvent through the component being flushed out. You would shoot it through the evaporator assembly as well. Your new compressor will come with PAG oil in it. Dump it out into a measuring cup and put the same amount of fresh PAG oil in the compressor, hook it all up, evacuate with a vacuum pump, put say 1.5 lbs of 134a in through the high side as a liquid ( can upside down) static,engine not running. That should be enough of a charge to get the A/C clutch to engage when you do turn the system on. Put the remaining Freon in through the low side service port as a gas (can right side up) engine running with the A/C on. You got that,right?
Thanks for the reply. The A/C kit does come with a new dryer and expansion valve. The process of cleaning everything out, how can I do that at home? Is there a cleaning kit I can hook up? What tools do I need?
 
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New o-rings everywhere there is a joint.. Use Nylog Blue o-ring lubricant. BTW it's not blue, its clear.
If the compressor is shot and scattered particles all through the system, you'll want to change the expansion valve on the evaporator too.
The drier/filter should have caught all the junk, but you never know till you pull it off. Mine exploded and scattered the little desiccant balls all through the line leading to the expansion valve and filled the expansion valve too. That's why its a good idea to flush the lines with solvent, to wash out any contaminants, including the non-compatible compressor oil.
If you are changing all the o-rings and the other components, there is no need to use the PAG with dye. The dye is actually a contaminant and is not needed.

Change all the Schrader valves to
"Change the Schrader valves". Are those the valves on top of the compressor that need to be removed and adaptor valves added? Did my original post have the correct parts in the links?
 
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I just got my EPA license and bought some R12 and kept the system all original. It works great. EPA license is only like $25 or so. You take the open book test and they send you a license with a # you can use to legally buy restricted refrigerants.
 
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As I research more on this process I realized the expansion valve is located in the evaporator assembly. Should I go ahead and buy a new Denso evaperator core and replace it while I am in there? It's an extra $100 bucks, but I'd rather do this correctly the first time!
 

fjc-man

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I think I’d take a chance on the expansion valve. Install the new compressor and drier (after the evaporator and condenser unit flush) and draw a 28 inch vacuum on the closed system, close off the gauge valves. Wait a half hour and if it hasn’t leaked down, charge the system and check operation. If everything is good, great! If the expansion valve isn’t letting the system work correctly,🤦‍♂️ Then tear the dash apart to get the evaporator out.
 

flintknapper

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New o-rings everywhere there is a joint.. Use Nylog Blue o-ring lubricant. BTW it's not blue, its clear.
If the compressor is shot and scattered particles all through the system, you'll want to change the expansion valve on the evaporator too.
The drier/filter should have caught all the junk, but you never know till you pull it off. Mine exploded and scattered the little desiccant balls all through the line leading to the expansion valve and filled the expansion valve too. That's why its a good idea to flush the lines with solvent, to wash out any contaminants, including the non-compatible compressor oil.
If you are changing all the o-rings and the other components, there is no need to use the PAG with dye. The dye is actually a contaminant and is not needed.

Change all the Schrader valves too.

^^^^^

This would be my advice exactly.
 

flintknapper

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As I research more on this process I realized the expansion valve is located in the evaporator assembly. Should I go ahead and buy a new Denso evaperator core and replace it while I am in there? It's an extra $100 bucks, but I'd rather do this correctly the first time!

IF the original compressor failed because it 'seized' then likely small metal particles migrated through the system and NO the drier and Evaporator will not catch all of it (if the pieces are small enough). Also, desiccant in the drier will break down over time and plug your TXV, it looks like fine silt.

You can flush SOME condensers and evaporators....but its not worth the effort. Neither are particularly expensive. I would replace them.

A/C work is tedious and full of potential pitfalls for the novice. Do it ONCE and do it RIGHT. You'll be rewarded.
 
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The evaporator assembly has to come out of the truck and then it gets split in half to get to the expansion valve.
IF the original compressor failed because it 'seized' then likely small metal particles migrated through the system and NO the drier and Evaporator will not catch all of it (if the pieces are small enough). Also, desiccant in the drier will break down over time and plug your TXV, it looks like fine silt.

You can flush SOME condensers and evaporators....but its not worth the effort. Neither are particularly expensive. I would replace them.

A/C work is tedious and full of potential pitfalls for the novice. Do it ONCE and do it RIGHT. You'll be rewarded.
I think it would be worth the extra cost and money as I have no idea why the original system no longer works. Scared to ask this but since I am basically replacing the compressor, condenser, dryer, evaporator, and expansion valve, should I also replace the rubber lines (Toyota labels them
a/c refrigerant discharge hoses). I guess if I do that, I only need to clean out the hard lines and be done with it. s*** better be arctic cold after this!
 
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I replaced the rubber lines when I did mine. The system didn't work when I took ownership; took the nuclear approach and changed everything.
SOB will freeze your a$$ out on 100+ days!
 

flintknapper

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The evaporator assembly has to come out of the truck and then it gets split in half to get to the expansion valve.

I think it would be worth the extra cost and money as I have no idea why the original system no longer works. Scared to ask this but since I am basically replacing the compressor, condenser, dryer, evaporator, and expansion valve, should I also replace the rubber lines (Toyota labels them
a/c refrigerant discharge hoses). I guess if I do that, I only need to clean out the hard lines and be done with it. s*** better be arctic cold after this!

I would. Then flush the hard lines. Basically have a new system. When properly installed and charged should give you nice cold air and last a long time.

AC1.jpg
 
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Called Toyota Parts Overstock and the two hoses are discontinued. They don't seem to be available on the other cruiser parts sites either. There are plenty of 93-97 but not 91. Can the old ones be rebuilt with new rubber? BTW, here are the part numbers
A/C Refrigerant Discharge Hose
Part Number: 8871160140

and

A/C Refrigerant Suction Hose
Part Number: 8871260160

I'm guessing you still have your old lines? If so, take it to a A/C shop, have them cut the ends off and make with new lines...
 
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Where do y'all in the Dallas area go to get your R12 evacuated? I have been calling everywhere and no one has the tools, even the Toyota Dealership! How is that possible? I cannot live with myself venting that crap into the atmosphere.
 

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