Even if you do find a way to R&R the heater core without disturbing the AC system, it is a time consuming, detailed job. It requires removing the dash to obtain access to the HVAC box where the heater core and evaporator are located. I agree with Bob - if you do go to the trouble of tackling this job, might as well replace the evaporator while you're in there. Of course, that will mean evacuating the freon from the system by a professional - it cannot be legally released to the atmosphere.
I had a '92 Acclaim that had the heater core develop a leak at 300K miles. As Bob suggested, I connected the heater hoses together, bypassing the core. Of course, this meant no heat and I ended up driving the car for 6 weeks in the dead of winter (January 2003) until I could remedy the problem. My "fix" was to purchase a '90 Acclaim with a working heater core and eventually junked the '92. I just did not have the time nor funds to R&R the heater core on the '92. In the end it was cheaper to buy the '90 than to fix the '92.
Good luck!
I had a '92 Acclaim that had the heater core develop a leak at 300K miles. As Bob suggested, I connected the heater hoses together, bypassing the core. Of course, this meant no heat and I ended up driving the car for 6 weeks in the dead of winter (January 2003) until I could remedy the problem. My "fix" was to purchase a '90 Acclaim with a working heater core and eventually junked the '92. I just did not have the time nor funds to R&R the heater core on the '92. In the end it was cheaper to buy the '90 than to fix the '92.
Good luck!
