And depending what is wrong with it, depends on whether or not it can be refurbished. 56 and 57 compressors are the same with a mention in one authenticity manual, 56 has a site glass and 57 does not but that means very little depending on what was installed or later installed. The bellows style crankshaft seal is a great determination of whether a compressor can be restored, if available?? If somebody doesn't know what they are doing, and damages the brass bellows on the crankshaft seal, the seal is ruined. If the carbon seal ring has minor wear it can be lapped down on glass and with ultra fine lapping compound IF YOU KNOW WHAT YOU ARE DOING!!!
I did this with mine years ago before the internet and before knowing about Classic Auto Air including using a Jewler's magnifying glass to inspect the carbon ring as I lapped it. Yes it is sealing but if your seal is wrecked you have to find NOS which is very seldom or a good used which are hard to find.
The clutches are harder to locate than the compressors and the Continental division used a piss poor design clutch on the Mark II. Years ago I was strongly warned you simply do not throw the switch on for AC if your engine is running fast such as on the highway because the sudden jolt of this lousy clutch will snap the flex plate spring on the clutch disk and you only turn them on at slow idle and leave it on or shut it off and leave it off until the engine is idling SLOW!
If you want to totally destroy your compressor, walk up to the car with a 1 pound can of R12 and "top it up". Yes you can destroy it because when refrigerant is lost, usually the refrigerant oil is lost with it. Keep adding refrigerant without checking the oil and watch your compressor burn out and pollute the entire system with metal filings as it burns out. This was the fate of mine before I got my Mark II.
You will see an HH Tecumseh for sale from time to time and I saw one for sale a number of years ago from a Desoto of 1955 vintage. I got it cheap enough but when I recieved it, yes it is an HH like on our Mark II BUT the orientation of the fittings and other features is different indicating different flavors of these compressors bearing the HH label. The clutch on this Desoto version? It was 1955 but instead of the crap the Mark II uses, this one has the electromagnet bolted to the compressor like ALL modern units from later instead of the brushes and spinning electromagnet like our Mark II compressor. Because of this design the compressor could be operated using a thermostat instead of the throttle valve to control the temperature.
Due to the crap we have and it's fragile nature is why they are hard to locate.
As for my Desoto gamble, the inside was like brand new with parts interchangeable but I don't have the desire to part it out due to how difficult they are to locate. It is likely rarer than the style on our Mark II.
If you want to destroy your compressor, ship it with the clutch still on🤬🤬. Mine was shipped off to some outfit in Texas who I might add did a shoddy job of restoration, not even replacing the bearings with new along with gaskets hacked out by hand. Dennis Carpenter sells premium gasket sets so why chop out gaskets and I spent the time after obtaining better material and cut my own! They shipped it back with the clutch on the crankshaft. The AC wholesaler who I dealt with delivered it with cores using their truck and then picked it up using their truck. They PROPERLY packed it and Canada Post played football with it. I opened the carton to find the clutch laying loose with the tip of the crankshaft in the clutch. I blasted Canada Post along with my wholesaler and got my money refunded and ended up with a better compressor but with a busted taper tip off the crank. I sent the crank to a machine shop and they built up the end using brass and machined a new taper. When I installed the compressor, yes the pulley turns freely including with a new clutch bearing I also installed but when the clutch is engaged, the pulley has a nasty wobble. The crank is likely bent or not machined true, or the press on clutch hub is stretched out of round and causing the wobble. Since then I got a good used crankshaft and another clutch disk/hub assembly from Classic Air and I will pray the problem is the crank because my front clutch plate has better clutch fiber over the replacement. This or contact them for a hub with a busted flex spring and replace my hub with a replacement.
There is no provision for a clutch puller on these LOUSY clutches. It is called remove the bolt and install one slightly longer along with the washer and by longer, slightly longer so the bolt can be bottomed out only by finger, but leaving the washer to clutch hub slightly loose and while holding the clutch, get an assistant to use a punch and strike the bolt to pop the clutch off.
I did this by myself by supporting the clutch between my legs with the compressor hanging and gave the bolt a sharp hit popping it loose. You sure as heck want the compressor over a pile of rags and close to the floor because if the bolt breaks, the compressor will fall and is why I had a box full of rags below the compressor. This and REMOVE THE BRUSH ASSEMBLY first!! The bakelite brush levers that pivot against the copper rings are impossible to locate and while removing the clutch, the brush holder assembly can get destroyed. Again if you don't know what you are doing, keep your damn grubhooks off the goodies!
I was told years later that, that is what you have to do, to remove the clutch and having the compressor hanging while the clutch bolt is hit will prevent the compressor and the crank from shock and the possibility of bending the crank, damaging bearings and the seal but to remove the clutch. Don't use a claw or gear puller on the pulley as well because it could get bent. I have been working on mobile AC for a number of years and have an assortment of pullers but no provisions were provided on these. No threaded hole in the hub where a puller is used to push against the crankshaft or 3 small threaded holes on the clutch to install a puller to push against the crankshaft. NOTHING except supporting the clutch and stiking the head of a bolt🤣. I have worked with Sanden/Sankyo, newer Tecumseh, York, AC Delco/Frigidaire, Chrysler, and nothing as lame as these clutches😖