Tale of the heater-core
On Friday 5th of august, I had good hopes on removing the heater-box with the heatercore late afternoon just before dinner. The intension was to replace the water based heater-core for an electric heater. I bought a BMW Auxiliary PTC heater from a scrap yard which works from 12Volts. (Yes it will be very heavy on the current draw, 70Amps!)
It started like this: Unclipped the clips, unbolted the wipers.
Unbolt the heater box:
After some good pulling, tugging, wresting and eventually hurting myself in the process I realized the whole dashboard had to come out in order to get the heater-box out. I tried to take a short-cut by unbolting the support-bar, but that did not help much at all. The dashboard has to come out!
Late friday 12 of august I continued my work on the dash. In a matter of 2 hours I had the whole dashboard, and the support-bar out. That was quite easy! Reading various BMW forums really helped in understanding what to remove in what order. Here's the link that helped me with the dashboard removal: http://www.bimmerfest.com/forums/showthread.php?t=258312
Here's the removal of the dashboard and support bar.
Modifying the heater-box was done in less than an hour. A new blade in the knive, some careful measurements, and the cuts where made for the new electric heater element. A quick test yielded a temperature difference of 21C between in and outlet temperature. That should demist and defrost the Z3 wind-shield within a reasonable amount of time.
After this the reversal of assembly was even quicker. Everything appears to be working. No warning lights on the instrument cluster.