I don't know why I like this car so much but I do, it's a love hate relationship. I have been beating the problems out of this car one at a time and now when I think I am at the end of any thing else that could go wrong I find that I have no AC. The R12 is all gone suddenly last week. I am in the HVAC business for a living and work with air-conditioning every day but not on cars. I have determined that I have a leak in the evaporator. There is a strong detection of refrigerant coming from inside of the evaporator box. There are no leaks about the expansion valve, I am getting a strong detection from the openings of the evaporator housing and the detector will go off when sampling the air from the vents when the blower is first turned on. I am quite surprised that a copper evaporator could leak but it seems mine is leaking. Not wanting to put more R12 into this car at this time, I have blown out as much mineral oil as possible and replaced it with ester oil then charged with 134a for now the car cools OK but I am sweetening the charge every 3 days to stay cooling. My plan is to replace the evaporator and re-service the system with R12 when the system is leak free. Now to the part I need help with, this looks like a hell of a job, as best I can see the entire insides of the front of the car will have to be removed in order to get at this evaporator. I have looked at my Benz Shop Manuel CD and can find no instruction on this procedure. I am hoping that someone has in print the step by step procedure for this job or If any one has actually changed an evaporator in a 126 body before could they tell me what they can tell me about this job?
Any help will be seriously put to good use, Bruce Buchanan