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Old Jul 19, 2014 | 11:26 PM
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I'm sure someone can help me with this one. I have an early 77 with the A4 compressor and VIR. One of my hoses to the compressor is broken. I have access to a new set of hoses and receiver drier from a 78. If I'm thinking about this correctly. Couldn't I remove my VIR and join the liquid line from the condenser to the evaporator with an orfice tube? And use the 78 hose and drier. Or am I missing something?
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Old Jul 20, 2014 | 12:57 PM
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An orifice system and vir (valve in receiver) system are constructed differently from each other and are not compatible. Also, I doubt that the stock hose/manifold assembly from a 78 (with an R4 compressor) will be backward compatible with an A-6 compressor.

If all you need is new hoses, buy them. R12 refrigerant is neither common or inexpensive and not to be wasted on an experiment.
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Old Jul 20, 2014 | 01:13 PM
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I too had a VIR system on my 74. What your talking about is removing the troublesome VIR (Valves In Receiver) and convert it to a fixed metering device with an accumulator. The kit comes with everything you need to convert it over. Cost about 100 bucks for the conversion kit. Good luck!
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Old Jul 20, 2014 | 01:34 PM
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I guess where I should be more clear on where I'm going with this question. From what I can tell the only difference between an early and late 77 as far as I can tell is the evaporator and receiver drier instead of VIR and of course they changed the hoses. So if since I have access to all the other parts would it be sensible to change it to late 77 and up? Looking at pictures of the two evaporator's the only difference is the orfice tube on the later system. So my question was has any one ever tried to just install an orfice tube on the early 77 evaporator ? That seems to be all the VIR eliminator on a 77 would be doing. 76 and earlier would be a different animal completely.
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Old Jul 20, 2014 | 02:02 PM
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Your early 77 will have a small oil line from the evaporator to the vir, that line will have to be plugged off. If you can get the evaporator from the 78 also, it would be an easy swap.

Last edited by '75; Jul 20, 2014 at 02:07 PM.
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Old Jul 20, 2014 | 02:24 PM
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I just ordered the VIR eliminator kit from nostalgic air for $110 bucks looked easier than wrestling the evaporator out.
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Old Jul 21, 2014 | 09:33 AM
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Originally Posted by Doug's 77
I just ordered the VIR eliminator kit from nostalgic air for $110 bucks looked easier than wrestling the evaporator out.
I probably should have chimed in on this. I too orderd the VIR Elimination Kit from Nostalgic Air as well, however, the inlet and outlet of the Accumulator were positioned to where once it was connected to the evaporator, it wouldn't allow connection of the included metering block/oil line block. I went round and round with them, and even included photos showing this discrepancy. Even then, they assured me it would fit.

After this "end all" solution from the experts at Nostalgic, I went with a different VIR Elimination Kit from another manufacturer. Low and behold the Accumulator fit perfectly, and allowed proper connection of the metering block! If the inlet and outlet ports aren't configured properly on the accumulator, it ends up placing the metering block smack dab in the middle of the accumulator. This is how the kit I received from Nostalgic fit. Feel free to address this concern with them. When I get home this evening, I will take and post pictures of what I'm talking about, as I haven't sent the Nostalgic kit back yet. I'll show you pictures of the Nostalgic accumulator and the correct one for a C3 conversion.
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Old Jul 21, 2014 | 06:43 PM
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Originally Posted by Patro46
I probably should have chimed in on this. I too orderd the VIR Elimination Kit from Nostalgic Air as well, however, the inlet and outlet of the Accumulator were positioned to where once it was connected to the evaporator, it wouldn't allow connection of the included metering block/oil line block. I went round and round with them, and even included photos showing this discrepancy. Even then, they assured me it would fit.

After this "end all" solution from the experts at Nostalgic, I went with a different VIR Elimination Kit from another manufacturer. Low and behold the Accumulator fit perfectly, and allowed proper connection of the metering block! If the inlet and outlet ports aren't configured properly on the accumulator, it ends up placing the metering block smack dab in the middle of the accumulator. This is how the kit I received from Nostalgic fit. Feel free to address this concern with them. When I get home this evening, I will take and post pictures of what I'm talking about, as I haven't sent the Nostalgic kit back yet. I'll show you pictures of the Nostalgic accumulator and the correct one for a C3 conversion.
Pictures would be great when I looked at it online I thought that could be an issue but went with it anyways because it appears to use the same drier as the 77L and up. I figured it may take a little modifying to make it work. I will post what I come up with thanks for your help.
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Old Jul 21, 2014 | 06:47 PM
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It might help to take off the passenger tire and open the access panel that is right by the VIR. Work from the bottom for some of it, makes it easier.
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Old Jul 21, 2014 | 07:31 PM
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Originally Posted by Doug's 77
Pictures would be great when I looked at it online I thought that could be an issue but went with it anyways because it appears to use the same drier as the 77L and up. I figured it may take a little modifying to make it work. I will post what I come up with thanks for your help.
Here is what it looked like when the accumulator was connected to the suction. Note the location/position of the high side inlet to the evaporator, and where the included metering block must connect.







Here is a photo of the kit I received from Classic Auto Air. After the nightmare with the first conversion kit, I wanted to make CERTAIN we were both on the same page before ordering. Not only were we, he knew EXACTLY why the kit I received from Vintage wouldn't work, and further explained the C3 VIR kit has a unique to C3 conversion accumulator. Note the different location of both evaporator inlet as well as the outlet on the accumulator. This allows the the metering block to properly connect, as well as the oil return line. (which internally I believe is simply blocked off within the metering block itself).






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Old Jul 21, 2014 | 08:13 PM
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Thanks Patro46 for the pictures I will keep you posted with my progress
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Old Jul 23, 2014 | 10:17 PM
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Ok the kit came in today after several hours of twisting and turning I finally took a tubing bender tot he evaporator lines. I wouldn't recommend the nostalgic kit it takes a lot more than it should to make it fit. But it's in now on to hoses and compressor.
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Old Jul 28, 2014 | 10:06 PM
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Finally after 30 some years of no ac I have cold air. Still needs a little work but I am very happy with the progress.
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