From someone who has problems posting to this group, but who can read it ok.
From: Fiacc Larkin Subject: heater problem Date: Sun, 04 Dec 2005 23:15
"I have a BMW 96 316i E36 M42. Ive been having serious overheating problems. My cooling system is somehow accumulating air to the point that the fan wont kick in (presumably because an air lock is blocking the fan sensor) and once that happens it doesn't take long before it overheats. The annoying thing is that if its bled and topped up with coolant she'll run perfectly for another week or so until the same thing happens again. I took it to the dealer who just bled the cooling system and said it wouldn't happen again. needless to say three days later it did. Obviously the air is getting in very slowly so its gonna be very hard to find, right? where should I start looking?"