Heater malfunction

[Russkcpa]

For my 73 Tii:

Heater-defroster definately has some issues

If I am driving and my heater is on I can feel cold air (fresh air) coming through the vent AS WELL AS the "diluted" warm air. Obviously something with my cable controls is screwed up (not shutting off the fresh air)

My Heat/Defrost cables are a little quirky anyway (defrost has to be engaged in addition to heat to get full blowing at my feet)

Any help is greatly appreciated

Russ

[Brandon]

My best advice would be to pull the box (or find another) from the car and rebuild it. Once out of the car, there are two rivets on either side, drill them out and then you can get into the box. Now you get at all the cables so you can lubricate/adjust/replace them, and you can replace the factory felt (seal) on the vent shutters. Good time to remove the fan blower motor and clean and lubricate too.

[Biscuit3]

Yee, my car has a similar deal to your's. If I put the "thermostat" on hot, cold air comes out, but if I put it on cold, hot air comes out. It's all ass backwards in Australia, I've been saying that for years! But I shoved rags in the two corrigated black plastic pipes that attach under the console, so now no hot air comes out at all which is a good thing too. It's not very fun slipping and sliding in Karl in the summertime which is a week away here!

[Mike Self]

Ms Biscuit--the fix for your heater is easy--you (or a PO) have the hot water valve control cable hooked up backwards. Look at another '02 whose heater is functioning correctly and then look at yours. The Fix is easy: just unbolt the control arm from the water valve and reposition it so it's like the "correct" car's setup. DO NOT disconnect the cable from the control arm--it's a real PITA to reinstall.

Russ: the problem on your heater is most likely the control cable that works the hot water valve and the "cold air mixer door." This is a dual cable that is connected to the temp control lever on the dash. As you move the temp control from cold to hot, this dual cable moves the water valve lever and also gradually closes the mixer door, so when the heater is set to full hot, the mixer door is fully closed. I suspect that the mixer door cable is either stuck or broken.

Two ways to tell: scrunch your head under the dash and move the temp control lever while observing the two cables hooked to it. They should both move. Then, have someone else move the control while you look down thru the heater blower with a strong flashlight--it may help to have the fan running to see better--and see if you can watch the mixer door open and close. It's just below the fan.

You might be able to unstick the door by poking around with a long screwdriver thru the footwell heater outlets, but if it's really stuck or the cable's broken you're gonna have to pull the heater. Lotsa FAQs on that job...

Good luck--hope you can unstick it.

mike

[Russkcpa]

Mike

Thanks very much

I have my 76 2002 that is fine so I can look at that setup

I'll report back to you

Russ

[ingraham]

http://www.bmw2002faq.com/content/view/73/32/