keverson

I replaced all AC components but the evaporator. Had the system vacuumed and guess what is bad!!! I have never replaced one of these. Any tips from your experiences? Thanks!

Ozzie

First be very sure that the evaporator is leaking. You said that you vacuumed the system. I don't know how to tell where the leak is by only applying a vacuum. Assuming it is leaking:
1. The EPA doesn't want you to discharge the refrigerant into the atmosphere. You're supposed to be certified and have the correct tools to work with the refrigerant.
2. The system must be discharged to continue.
3. Disconnect everything attached to the right hand filler plate and remove the plate.
4. Disconnect refrigerant lines from the suction and expansion valves.
5. Cover all connections to keep out crud & moisture.
6. Remove screws securing the evaporator case. Remove case & evaporator.
7. Separate the case.
8. Remove expansion valve.
9. Remove clamps securing the valve and evaporator pipe.
10. Disconnect all lines and remove suction valve.
11. Remove the screws securing the evaporator to the case.
To assemble, reverse the procedure. Always use two wrenches when loosening or tightening refrigeration fittings. Flare nut wrenches are best. Use refrigerant oil on all connections. Add the correct amount of oil to replace what was lost in the old evaporator (usually 3 ounces). There are different quality evaporators on the market. Try to get a good one so you don't have to redo the job in a short amount of time. If you can get the kind with copper tubing it has less chance of leaking. And if you're watching the certified man charge the system be sure to wear safety glasses in case of a blowout. Liquid refrigerant in the eyes will damage them.

69442C

Here is a thread that covered the replacement of the evaporator along with a lot of other work. This should give you a good idea of what you are facing. Since I assume your car is fully assembled, you will need to remove the the passenger side wheel and wheelhouse to gain full access to the evaporator box under the hood. And if you decide to do this project, I would also replace the heater core and the blower motor too. You will have the blower motor right in front of you and the heater core is just a few more steps to get it out. The heater core replacement is also covered in this same thread.

If you do replace the heater core and if yours is original, you will likely find a brace that is soldered between the 2 tubes coming off the heater core. The replacement heater cores do not have the brace. I would suggest unsoldering the brace from the original core and solder it onto the new one. It does add stability to the tubes.

Brian

https://classicoldsmobile.com/forums...storation.html

keverson

Sounds like a big job! Thanks for the replies. They may have done more than just vacuum the system. They showed me right where it was leaking. The new part arrives this week so I will get to work. Good suggestion on the blower motor and heater core!
Thanks

keverson

It only took about an hour to remove the evaporator box. Not bad at all. The new evaporator from The Parts Place will be here Thursday, then it all goes back together.