81 Rabbit diesel A/C Issues

I'm halfway through the long process of bringing back an 81 Rabbit diesel from the nearly-dead. It has A/C, though I'm not certain it is
original since the control on the inside, a rotary switch affair, seems patched in. Anyway, the compressor turns but seems too stiff - caused the belts to squeal back when I tested it, before starting teardown work (can't run it right now).
I'd love to have working A/C but don't have much money. I see seal kits for converting to R-134a. If some of these seals go into the compressor, it seems I'd have little to lose trying to install them, maybe in the process I can free up the stiff compressor. But I can't find any decent instructions for disassembly/reassembly of the compressor. If I can't rescue the old compressor, it won't cost more to get a rebuilt one whether I try digging into it or not. Even rebuilts are serious money :-/.
So has anyone worked on a compressor and is there decent instruction on the net? My Bentley manual says nothing.
An aside, anyone know an economical source for the cold-start cable? The cheapest I can find is $40 X-(.
Tony
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I added a AC on a 78 diesel and can tell you first hand it will never work right. They were originally added on the diesels but the newer ones from PA had it put on at the factory but still problems. You will have bracket and belt problems you would not believe. When the A2 body type came around in 85 they mounted the compressor and alternator along with a power steering pump much better. VW bought a aftermarket ac company in Texas and used their brackets and was very slow to move away from them.
JoBo

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Thanks for the info JoBo. I guess I should look carefully at the brackets and pulley alignments before doing anything else with the existing AC. The alternator belt was broken when I got the car, so I've got to loosen the compressor and remove its belts in order to replace the alternator belt. Does the compressor bracket tend to get bent or work loose or such? Mine has no PS.
It's a little hard to see into the pulleys area, but at first glance it looks like what the manual shows for brackets & belts. There's nothing odd inside the cabin, except for the rotary control ... the evaporator housing & such looks like what the manual shows. I'm a tad puzzled by the mix of proper & unusual on this beast. The car is new to me.
The Bentley manual says precious little about the AC control system. I'm guessing there have to be some extra relays and such somewhere to turn the compressor and the radiator fan on & off according to the thermostat. I'm also guessing that the rotary control tacked into the dash is a thermostat adjustment.
Jo Bo wrote:

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I have an 82 diesel, dealer installed AC. The main v-belt drives the water pump and AC compressor which has two pulleys. A second thinner shorter v-belt drives from the compressor to the alternator mounted on the top. Alternator alignment, belt wearing big problems. Motorola lasts ~80k, Bosch ~50k from the vibration. Got a second Motorola and switch them off, rebuilding other for a next failure. My coaxial control works 3speed blower also temperature adjust that triggers compressor directly. Radiator fan relay is part of normal car, but AC switch on now causes radiator fan to run continuously. Shop says I got DFW compressor (texas). 310k and counting. rich
backwoods wrote:

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Thanks Rich. What you're describing for belting arrangement is exactly what I've got. I haven't played with the A/C control in the dash, but it appears to be just one knob. The regular heater control seems to still take care of the blower speed, but I didn't get a chance to toy with it before teardown. Thanks for the heads-up about the alternator. I'm guessing what you're talking about for rebuild is that the bearings fail due to vibration? I'd best hunt up a backup before I put her back on the road. It is a Texas car, so maybe the Texas dealer put in the A/C. 310K is majorly impressive, so I have high hopes now LOL. My beast has a bit more miles, but was towed behind a motorhome a lot of the time, so engine miles are hopefully a good bit less.
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Hello, I had three A-1 VWs, the truck was rear ended, I have a 1979 rabbit, and 1984 Jetta, both factory AC brackets and such, I do AC a lot. A stiff compressor could be the bearings inside, or the clutch bearing. I am not trying to insult you, I dont know what you were turning I am guessing, I have not seen a VW compressor apart. I have taking apart other compressors. some I needed to show customers why the AC failed. broken vanes or bad discharge spring plate one very big tip. do not overtighten the timing belt, you will destroy the diesel fuel pump, it has no bearing, the housing is the shaft bearing. also do not overtighten the water pump belt, same deal aluminum housing is the bearing race for the shaft. maybe you knew that.
there are R 12 freon replacements, R 134a is ok but you cannot have R 12 oil anywhere in the evap, condensor or compressor. yes you could purge the system with acetone, but why. talk to a AC guy or look up freeze 12 or google search R 12 replacement I would keep the R 12 set up, R 134a has different operating pressures also only charge the system 75% of total charge capicity, or you could blow the condensor apart.
yes the belts need constant adjustments, but I like AC I like A-1 diesels Both are Turbo Diesels, I run 25% veggie oil I dont like the engine noise, but enjoy the 50 MPG.
"backwoods" wrote > I'm halfway through the long process of bringing back an 81 > Rabbit > diesel from the nearly-dead. It has A/C, though I'm not > certain it is > original since the control on the inside, a rotary switch > affair, seems > patched in. Anyway, the compressor turns but seems too stiff - > caused > the belts to squeal back when I tested it, before starting > teardown > work (can't run it right now). > > I'd love to have working A/C but don't have much money. I see > seal kits > for converting to R-134a. If some of these seals go into the > compressor, it seems I'd have little to lose trying to install > them, > maybe in the process I can free up the stiff compressor. But I > can't > find any decent instructions for disassembly/reassembly of the > compressor. If I can't rescue the old compressor, it won't > cost more to > get a rebuilt one whether I try digging into it or not. Even > rebuilts > are serious money :-/. > > So has anyone worked on a compressor and is there decent > instruction on > the net? My Bentley manual says nothing. > > An aside, anyone know an economical source for the cold-start > cable? > The cheapest I can find is $40 X-(. > > Tony
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Thanks for the explanation guys. Its nice to know that the A/C coming on with the defroster is simply to make the defrostting/defogging work more efficiently.
Cheers, Bryan
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