My 1990 XJ6 has a leaking heater core. Can anyone help me with directions on how to replace the heater core?

 

Firstly, grab yourself a haynes manual... it will come in very handy and has the instructions for this proceedure...

Second, it's located under the dash, so you will need to
1. drain your cooling system,
2. remove the under dash panels on both sides,
3. remove the glovebox (watch out for the very sharp metal bracing and wrap it in something to prevent cutting yourself to pieces),
4. on passenger side - remove screws holding the plastic cover where the heater pipes enter the housing,
5. remove the 4 allen bolts holding the two pipes to the heater core,

on the other side -

6. unbolt the diamond shaped climate control computer and pull it down and away from the housing,
7. remove the 4 small screws and remove the plastic plate over the heater core (right behind where the computer was),
8. carefully slide out the heater core out from the right side of the heating/air con housing....

refitting is the reverse being careful to make sure all the insulation is in place and also fit new 'o' rings where the heater pipes enter the core

Refill the cooling system, check for leaks

I'm sure others will chime in with some more appropriate responses...

 

Very helpful, instructions. Thanks for that.

 

Thank you for the information Jagfix38. That will be helpful when I get to the heater. Unfortunately, some other more urgent issues have arisen. Seems like that is getting to be a weekly thing.