I was wondering if someone could send me in the direction of a step by step process on how to change my evap core. I've done my heater core but my Haynes Manual and the books from the dealer aren't very descriptive. I know I need to be careful with the blend door actuator. But my brother in law seems to think it'* a 2 day job. I don't remember the heater core taking that long.... Thanks in advance.

This is from my Alldata for my 97 Bonneville.

Remove or Disconnect

• Recover refrigerant.

1. Cross car brace.
2. Rear engine sight shield. Refer to Engine Cover Replacement See: Engine, Cooling and Exhaust\Engine\Service and Repair.
3. Accumulator.
4. Booster cable from multi-use relay center.
5. Position under hood fuse block out of the way.
6. Blower control module.
7. High side line form evaporator.
8. Blower motor.
9. Wire harness clip from HVAC module.
10. Accumulator bracket.
11. HVAC module heat shield.
12. Accessory drive belt.
13. Generator.
14. Cut top side of HVAC module insulator following cut line.
15. Raise and support vehicle.
16. Cut bottom of HVAC module insulator following cut line.
17. Lower vehicle.
18. Fuel line clip from HVAC module.
19. Insulator from module.
20. Bolt attaching heater and A/C module assembly. Inside vehicle.
21. Blower module from HVAC module assembly.
22. Evaporator core.

Install or Connect

1. Evaporator core.
2. Blower module from HVAC module assembly.

Tighten

• Bolts to 5 N.m (44 lb. in.).

1. Bolt attaching heater and A/C module assembly. Inside vehicle.

Tighten

• Bolts to 5 N.m (44 lb. in.).

1. Insulator from module.
2. Fuel line clip from HVAC module.
3. Generator.
4. Accessory drive belt.
5. HVAC module heat shield.

Tighten

• Bolts to 5 N.m (44 lb. in.).

1. Accumulator bracket.

Tighten

• Screws to 6 N.m (53 lb. in.).

1. Wire harness clip to HVAC module.
2. Blower motor.
3. Blower control module.
4. High side line to evaporator.

Tighten

• Accumulator connections 24 N.m (18 lb. ft.).

1. Blower control module.
2. Reposition under hood fuse block to its original position.
3. Booster cable from multi-use relay center.
4. Accumulator.
5. Rear sight shield. Refer to Engine Cover Replacement See: Engine, Cooling and Exhaust\Engine\Service and Repair.
6. Cross car support.

•  
  • Evacuate, charge and leak test A/C system.

Thanks. I have another question though. I'm replacing the evaporator core, the accumulator, and the compressor along with flushing out the entire system. How much of the pag oil am I going to need? The Freon that I have says it'* a 19oz can with 16 oz of Freon and 3oz of oil. I have two of those cans. Is the oil in that the same as the pag oil and if so how much more oil should I add?

From Alldata.

Let me ask you this. How are you doing all this? Are you actually using a vacuum pump to evacuate the system?

Yep. I rented the vacuum pump and manifold gauges from AutoZone so I can do it the right way. I wasn't going to pay the shops in my area almost $200 to do it for me.

Then you just need to get the refrigerant and oil separate.

Too bad they didn't have nitrogen cans for projects like this. Its one thing to pull a vacuum on an A/C system and watch the gauges over night, but there is no way to pressurize the system without contaminating it, unless you were to pressurize it with nitrogen. This is to test the seals prior to dumping all that new freon into it.

Ok. So I started at 1030 a.m. I finished around 9 p.m. we were gone for about 3 hours running around getting last minute items. So I figure about 7.5 hours to do the compressor, the evaporator core and the accumulator. I also cleaned out my condenser and all my lines. We put the vacuum on it and shut the manifold gauge valves accordingly. The high and low side ports still have the gauge connectors on and are open to check for leaks overnight. I've replaced everything but the condenser btw. I feel like an idiot even asking this but what'* the proper process for recharging the ac. I mean with the vacuum pump and all. My compressor came with 7 oz of oil in it. I've got a 3 oz. can to add. Is that ok considering my system was bone dry and we ran brake cleaner through the condenser. I was told I should be able to add a can of Freon, add the oil and then add more Freon. My biggest concern is the recharge process. We are in the garage. It'* air conditioned and kept at 70. If someone could tell me what psi it should be at and the proper way to recharge with the vacuum pump and such that would be greatly appreciated. Again I feel stupid but I just want to be safe so as not to destroy all of my new components.

If you go by the chart above, and your compressor already has oil in it,
3 more OZ for the EVAP
1 more OZ for the condenser
3.5 more OZ for the accumulator.

For a total 7 more ounces of oil. This is not counting what'* already in the compressor.

Once you have pulled a sufficient amount of vacuum, you can now remove the pump.

Start the car, turn the HVAC to MAX A/C. (it won't do anything right now, so no worries)

Add the rest of the PAG oil to the system. The cans are under pressure, just hold upside down from start to finish until all cans have been emptied.

Now, add your R134a in the same fashion. Once you have put some in, you will notice the compressor kick on. Continue adding the required 2.2 lbs of freon until all gone.

Enjoy your new A/C.

couple tips to add, it goes better if you lay the can on something hot and shake it a bunch of times