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1983 280CE Euro!
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Discussion Starter #1
The air conditioner in my '83 280CE euro model with automatic climate control is blowing warm air. I took the car to an air conditioner place for an evaluation and they told me that someone change the R12 for R134 even though they did not change the fittings, also the system have some air.... so....I put the new fittings(blue and red) I emptied the system, used a vacuum pump and make sure it was complete empty using gauges. I put two oil cans of 2oz each, one can of r134 w/dye, and at this point the compressor (York) started working, but when I was on my second can of refrigerant (r134 only) only half of the can when in and the system would not take more . The gauges indicated about 100psi in the low port. What is the problem???? How can I fix it? I want to have a nice summer:crybaby2:
 

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1978 280ce euro found dead on Ebay
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What does the high side say? you should have 30-40 psi on low side not 100PSI.

Also oil for York compressor is added when system is empty from side oil fill fitting. You use a curved dipstick to determine oil level.

Get the highside and lowside pressures and the outside and inside vent temps. From that you can search the net and find out what is wrong from one of the Air conditioning sites and fourms or somehere who knows AC dianogstics better than me.

I know one site has a good table.
 

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1983 280CE Euro!
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Discussion Starter #3
Hello my old friend! Thanks for your help! Where is the oil filling port for the York compressor? I checked and did I not see anything that resembles a fitting other than the low and high pressure port.
The high side is 75psi and the low is 70psi (I recheck it again).
I review other post in the forum and did not find an answer..... I presume that the system is close somehow but ...where? does it make any sense?
 

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1978 280ce euro found dead on Ebay
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Hello my old friend! Thanks for your help! Where is the oil filling port for the York compressor? I checked and did I not see anything that resembles a fitting other than the low and high pressure port.
The high side is 75psi and the low is 70psi (I recheck it again).
I review other post in the forum and did not find an answer..... I presume that the system is close somehow but ...where? does it make any sense?
That's right pressures if the system is not running sure your clutch is engaged? As for oil fill it's just a bolt on side of compressor you pour oil in liquid form through bolt hole, don't remove it now that you have freon in system.
 

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1983 280CE Euro!
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Discussion Starter #9
air conditioner.....help

That's right pressures if the system is not running sure your clutch is engaged? As for oil fill it's just a bolt on side of compressor you pour oil in liquid form through bolt hole, don't remove it now that you have freon in system.
I found the oil bolt, Thanks!:) now... what kind of oil does this compressor use? Where can I find it? How do I know if it has enough oil? Is there anything else that I should know about York compressors?.........and Yes, the clutch is engaged, the blower is running, but not cold air and is not taking more refrigerant
 

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1983 280CE Euro!
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46 Posts
Discussion Starter #10
air conditioner.....help

That's right pressures if the system is not running sure your clutch is engaged? As for oil fill it's just a bolt on side of compressor you pour oil in liquid form through bolt hole, don't remove it now that you have freon in system.
I found the oil bolt, Thanks!:) now... what kind of oil does this compressor use? Where can I find it? How do I know if it has enough oil? Is there anything else that I should know about York compressors?.........and Yes, the clutch is engaged, the blower is running, but not cold air and is not taking more refrigerant
 

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1978 280ce euro found dead on Ebay
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You use a dipstick to measure the oil attached file has plans for one you can use a wire coat hanger to make one. You can also buy them at AC supply stores. As for oil to use you need to use oil that is compatible with your refrigerent. When you converted to R134 you should have changed oil to ester oil. R12 uses mineral oil, it will not mix with the R-134a refrigerant. That is why you need to change it to Ester oil, because it will mix with R-134and lubricate the system components. Suck out the mineral oil and add ester oil you got R134 and PAG oil in the hoses then use PAG oil Viscosity 46in compressor.

see attached file for oil change proceedure.
 

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1983 280CE Euro!
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Discussion Starter #13 (Edited)
It's fixed!!!

Here's what happened: Looks like my compressor was bad, when we put oil in and charged it up, it was slipping the clutch and wouldn't turn by hand. So, I went to the trusty U-Pull it. And guess what? there was a butt ugly orange 80's mustang 5.0 that had a very similar compressor. It was $13. It had been painted black recently which led me to believe it had been rebuilt at some point. It had a different clutch so I took the clutch off of my dead york compressor and put it on the motorcraft. Then, after looking all around town, I found that Pep Boys sells an ester oil by castrol that is synthetic, and compatible with both R-12 and 134a lubricants. I filled the motorcraft compressor with 8oz of that, then it bolted right up to the mercedes bracket, while at the same time installing the new dryer from NAPA (it was only $18 there by the way)

I sucked all the air out of the system with a vacuum pump, filled it, and oh no!!! it didn't work! it was kicking on and off over and over. After hours of poking around here and there, I noticed that the motorcraft compressor has the suction side on the left!!! The Ford compressors have the suction and discharge sides backwards!!!

So, I emptied it again, switched the hoses, ran the vacuum pump once more, and filled it with some PAG and almost 3 cans of 134a. And it started working!!! yay!!!

Now, there's AC in my Merc, just in time for the heat wave here in PA. Thanks a lot everyone, it was my first AC repair project and I have learned a lot here.
 

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Yes tomorrow supose to be HOT on the east coast. $13 for compressor Great deal. Glad you got it running. DO you have and instant read thermometer to measure your vent temperature? Let me know on my post what it is.
 

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I just converted my 1981 Mercedes 300SD from the old R-12 to the newer R134a system. The garage did the work. I provided all the parts including a new R4 compressor from four Seasons, PAG 150 with dye, dryer, both switches, and expansion valve. I had to leave for a time and when I got back they were pulling it into a vacum for 30 minutes which held and then charged the unit with R134a at about 95% of orginal charge. They said they were unable to replace the expansion valve because it needed a special tool also that the unit was so clean that it did not need to be replaced. Low side presser is about 35lbs high about 125 at 2000RPM. Problem is that I am only getting 54 degrees out of the vents whereas the R-12 was putting out 45 degrees. Outside temp was at 77 degrees and that only gives me 23 degrees difference and it should be at least 30 degrees between the two. Any ideas on how to correct this or is this what to except with a R134a system. NOTE: Just got back from a 100 mile run outsidr temp was 82.2 degrees, vent temp was 57.2 degrees. Also the 2oz. of BG oil was added after the unit was fully charged. UPDATE: I removed 6 ozs. of R134a and the oil that came out with it then took the car down to Arkansas, a 250 mile trip and got the vent temp down to 45 degrees. This was more than the 30 degrees I expected as the outside temp was in the 80s. Advice: don't overcharge with 134a, and forget about the sight glass it is for R-12.
 
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