Heater core replaced

[maxbraketorque]

I finally made the time to replace the heater core in my 2000 XJ. There is lots of info on this and many video tutorials, but I'll add a few comments based on my experience:

• Angling the dash out of the way works pretty well. I was worried about damage to the dash or remaining connecting wiring, but its a non-issue if the dash isn't angled out too far. If anyone is interested in knowing, the driver side of the dash is supported by the steering wheel column support bracket when the dash is tilted out. The bracket has an upward slope to the surface on which the dash rests, so as the dash is tilted away, the dash gets raised up a bit on the driver side. The dash can only be angled so far before there is a risk of the dash falling off the bracket, so watch that closely. And going too far can add strain to the two connected wire bundles.
• Remove the two bolts attaching the dash to the door frame. This is needed because the dash has to be raised as it is pulled away from the firewall, and if the two bolts are still partially screwed into the door frame, the dash can't easily be raised.
• Disconnect the AC dryer can from its mounting bracket before separating the AC lines. Makes it much easier to disconnect that one line.
• When I was removing the AC box from the firewall, it got hooked on the insulation attached to the interior side of the firewall. I had to give it a pretty strong yank to get it out. Was a bit worrisome because I didn't know what was hanging it up until I finally got it out and inspected.
• In order to more easily get the AC box past the dash, I rotated the front downward. This helped a bunch with clearance. If you do this, make sure the heater core has been blown out first.
• My new heater core didn't come with an insulation strip. I found that insulation was only needed on 3 sides to get a sufficient seal all the way around and prevent any vibration. My main point here is that there is no need to get carried away with the insulation strip.
• The insulation and moisture catch on my evaporator core where in great shape. I just rinsed out the air flow passages with water and let it dry.
• The foam seal that goes around the heater core and evap lines at the firewall was fairly rotted around the heater core lines. I made a new seal using some heat resistant closed cell foam sheet. The material needs to be 0.5" thick to make a good seal against the firewall. I used a dremel with a small grinding wheel bit to make the holes for the heater core and evap core lines. Worked well. The bigger challenge was getting the vacuum line through the seal without damaging the seal. I ultimately made a hole to the same diameter as the vacuum line, and then made a small downward slit below it that I patched with another piece of adhesive foam like that was done at the factory.
• Check that the blend door is correctly aligned before bolting up the AC box.
• The coolant leaked out of the AC box through the gap around the blend door shaft. As a result, coolant leaked down into the blend door motor gearing. I carefully cleaned it out with water, let it dry for a day, and then lubed with bike chain lube. Working fine, but if it stops working, its easy to access after everything is put back together.
• Before I reinstalled the AC box, I used duct tape to better attach the interior-side insulation to the firewall so that the AC box can be more easily installed (and if needed, removed again).
• Test out the HVAC system before fully assembling the interior.