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Rebuilding my ac system......help needed

2K views 22 replies 4 participants last post by  one life live it 
#1 ·
Hi all. Been busy with my ac system. I was able to reseal the denso compressor. Thanks to youtube. Replaced all the orings. New dryer ready. The condensor will be replaced. Had to buy from the agents. No aftermarket replacements available here anymore..... The inside of all the lines are in great shape. Even tbe compressor was in great shape.
I'm sticking to R12 in the system. So I sourced some mineral oil. From what I can gather the system takes 7.75 ounces or 228ml of oil. Do any of you guys know where I can get the breakdown for each component?
 
#2 · (Edited)
The oil gets carried through the system with the refrigerant. It must be injected in while adding R12 or while the system is under vacuum (your choice there). The component that really requires the oil is the compressor, which won't engage until you have enough refrigerant in the system to get cooling and lubrication. No need to add extra oil as it will just pool somewhere. Make sure you have replaced your pressure switch and relief valve (both mount to the drier).
 
#7 ·
If your A/C system was completely flush, you add the amount of oil required for the system. Otherwise, you should just replaced the oil needed for each individual component replaced. There is a list for this, but I haven't been able to locate it right now. For maximum cooling, you don't want too much or too little oil in the system.

Best to place oil in compressor and turn pulley by hand before installation otherwise inject as A.Cabral stated.
 
#3 · (Edited)
In conjunction with what others have shared I would ask that you might look at the Thermal Expansion valve located under the instruments and just above the accelerator pedal. This is true for a LEFT drive car. I am unsure about the RIGHT drive variant.

I know from previous repair history and personal observation on my car they do fail and leak. Its pretty easy to see evidence of this as the valve has a foam insulating cover set that soaks up the refrigerant oil & perishes.. Mine certainly were soaked with oil when I looked at the cover… looked pretty desperate..

I also found the fan or inlet side of the evaporator blocked with a fair amount of grey lint~like material, effectively blocking most of the airflow, which was detrimental to the cooling aspect. With this surface cleaned off, the airflow (& cooling) was greatly enhanced.

Good Luck

MBL
 
#4 ·
Thanks for the info guys. I had the system charged about a month ago with some dye added. Traced the leaks to the compressor manifold seal and to the 3 casing orings. The other leak or 3 were on the condensor. I took the condensor to a radiator repairshop in the hope that they could fix it.......only to learn that they were unable to detect any leaks, and that at 9 bars. I retraced my disassembly procedure,hoping that I spilled some uv dye on the condensor myself. Nothing else had any dye on them, the fans and shroud was good. Pressurised the condensor myself and twisted it slightly, to see if a little stress would reveal anything. Only one of the 3 uv spots showed a small bubble every minute or so.
From what i could gather on this forum, is that rather replace than repair. So the budget is now ruined with the new condensor on its way. Both pressure switches performed flawlesly when the system were under pressure.
The expansion valve sits on the opposite side than your lhd cars. Easy acces with no pedals in the way. The one in there looks quite new. The foam however is missing. I gave it a thorough inspection for any leaks. I think I will take my chances. I did order a new foam cover.

One other question though. Why do they supply green orings for the pipe connections and black nitrile orings for the pump and manifold orings?
 
#8 ·
I'm sure there is a component filling list somewhere. Went through all my downloads, but to no avail... Searching the web didn't help. Unfortunately I don't have a service manuel for the car, I'm sure it will be in there. I'm sure some helpful member with the right info will be along shortly.
However thanks for everybodys contributions so far.
 
#11 ·
Hehe. The smell.....we won't go into that:grin Doing a roadtrip with a cold ac system will justify it any day. Was seriously considering to convert the system to r134. But I still have more than 12kg of R12 in my garage. If the system holds the vacume and no more leaks that should last me quite some time.
I asked my dealer to disclose the info for the oil quantaties, but I drew a blank there.... pitty though. They don't touch these old girls anymore. All the old mechanics moved on and I guess the books moved into file 13. Hey guys that is just my opinion tonight. They are actualy very helpfull searching for parts and taking my cash:wink
 
#12 · (Edited)
Hehe. The smell.....we won't go into that:grin Doing a roadtrip with a cold ac system will justify it any day. Was seriously considering to convert the system to r134. But I still have more than 12kg of R12 in my garage. If the system holds the vacume and no more leaks that should last me quite some time.
Stay with R12 if you have/can get it. It's a lot colder (than a r134a conversion) and you can pretty much recharge it with just the sight glass. :)

They are actually very helpfull searching for parts and taking my cash:wink
Isn't that the truth!!
 
#16 ·
Hi again one life,

"The expansion valve sits on the opposite side than your lhd cars. Easy acces with no pedals in the way. The one in there looks quite new. The foam however is missing. I gave it a thorough inspection for any leaks. I think I will take my chances. I did order a new foam cover."

That makes expansion valve access so much easier though! Cool.

My independent MB guy, when I showed him this photo I took, said "That's where they all go." If bad, I'd expect yours to fluoresce as well…

Something I learned when doing my Exp valve last summer is that it takes two of the 1268350640 foam sleeves. one for each side of the aforementioned valve..

Good luck,

MBL
 

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#21 ·
Some other pics of my progress. The cooling system is also part of the refresh process. All new hoses, thermostat, duovalve solenoids and some wiper arm repaint with new rubbers on the arm pivots. New grommits through the firewall also. The waterpump was replaced in 2013 according to the date on it. I think we are good with that for now.
 

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#23 ·
Damn, our local dealer just confirmed that the condenser #1268302870 NLA. This after they took my money 3 weeks ago. Even confirmed a week later that the part was invoiced in Germany and ready to be shipped.......Today when I stopped by to enquire about the delivery, they gave me the bad news. I'm not a happy camper at the moment.
I have exhausted all other options in South Africa, nada, nix, nothing. I can not source anything localy. Nobody imports that anymore. Generic option is available, but then I have to make new brackets and change the line outlay! Not an option for me.
Been browsing the web this afternoon and it seems that importing one from the USA is a option. This will be a new venture for me. If I may, can I ask you guys for some input. Ebay has a couple of options, or is there a better way or supplier that I can aproach. As stated earlier I'm planning on sticking with r12 in the system.
 
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