when I turn on the A/C, the car becomes very sluggish. Also the car starts over-heating (normally does not go over 190-195F even in very hot weather)
IT goes over 210F...but I turn-off A/C right away....hardly use it even in hot weather.
Also, the car idles rough, lots of vibration vs shaking.
Rush
I went through this too
,, your york compressor is shot and you need a rebuilt replacement unit.
the big deal will be getting one with the magnetic clutch system still attached.
now i got my replacement from ebay, because it came with the clutch assembly.
mustangsunlimited.com carries the york compressor however they changed and no longer offer units with the clutch attached.
see here:
http://www.mustangsunlimited.com/itemdy00.asp?T1=54030+01
changing the clutch requires a puller and i didn't think i had the correct puller to do the job so i went for one with the clutch installed.
however you still need to take parts off the old compressor and install on the new on.
they make rebuild kits for the york, however if the piston cylinder is all worn out then a rebuild with a simple kit is pointless.
changing the compressor is pretty easy. the units come prefilled with oil, usually 134 oil, however you will need to drain it completely by poping the fill bolt because the oil may not be correct for your A/C technician and if has to change it later he will charge a ton for labor.
if the system is charged then you will want to have a A/C guy drain it properly you will be charged for it but you can work it into the re-charge fee.
so have the system drained and vacuumed out.
take it home, get the new compressor ready. pop the lines on the compressor and transfer hardware over, at this point you can stick with R12 or go to R134 conversion. install and reconnect as needed and hook up the belt again, and the clutch wire. replace the dryer, and go back to the a/c guy for a vacuum and pressure test then oil and refill on freon.
I never did an A/C system before but i rebuilt my entire A/C system from the ground up, and when i first got it running my compressor was causing the engine to overheat and lockup and the noise and vibration was terrible.
i replaced the compressor and it was night and day!!
so start looking into a York compressor replacement.
ebay link to a guy selling them with the clutch
http://www.ebay.com/itm/NEW-COMPRESSOR-WITH-CLUTCH-YORK-1964-1971-FORD-MUSTANG-/230462501447?pt=Motors_Car_Truck_Parts_Accessories&hash=item35a8a2b247&vxp=mtr
oh one thing i remember, my replacement york had a different clutch connector on it then OEM so i spliced it from the original bad compressor, so never throw anything out until the new system is 100% working. i kept my old compressor for about 2 years after i got my system going just in case.