92 164S a/c temperature control plastic shaft broken

karlcchen · #1 (**permalink**) 10-14-2006, 04:10 PM

I was wondering why temperature control is not working! Any solution?

Karl

karlcchen · #2 (**permalink**) 10-14-2006, 04:16 PM

Now it is broken, I noticed at coldest setting, stepper motor position doesn't push door far enough to coldest setting. I could use a long stick to move the door further. Maybe that's why 164 has weak A/C? Always mixing with warming air?

Karl

Alfisto Steve · #3 (**permalink**) 10-14-2006, 05:43 PM

Time for winter and manual shutoff valve in supply hose to heater core neat outlet from rear of head for summer weather until you can pull out blower motor.See Bob's (Black Alfa) show and tell for his pictures and our write ups.

karlcchen · #4 (**permalink**) 10-14-2006, 08:23 PM

If someone can change the temperature control to manual, same one used on older cars.

Karl

Alfisto Steve · #5 (**permalink**) 10-15-2006, 12:05 PM

Broken lever was your temperature control.

karlcchen · #6 (**permalink**) 10-15-2006, 01:50 PM

I mean have a level inside the car that connect to the temperarure level. so I don't have to climb out of the car when I am driving - not that it can't be done. Image how people would freak out when they see me pop the hood open and climb out of the car to adjust my tempature level with cruise control set...

Karl

Alfisto Steve · #7 (**permalink**) 10-15-2006, 04:32 PM

You will need to get a cable, vacumn or electrical motor control valve you can install in coolant hose to heater.

164TD · #8 (**permalink**) 10-16-2006, 12:21 AM

Quote:

Originally Posted by Alfisto Steve

You will need to get a cable, vacumn or electrical motor control valve you can install in coolant hose to heater.

karlcchen · #9 (**permalink**) 10-16-2006, 08:28 AM

Blocking the coolant flow at rear (to heater core) is a bad idea, not because of cooling though, but of heat distribution. Circulation makes engine heat up evenly before thermostat opens. This also makes heater start working before thermostat opens, but no engine designer is counting on using heater core to cool engine. Drivers have "free will" not to turn on heater (no air passing it) at all. It is OK to by-pass the heater core with another hose as long as circulation is maintained.

I just want a manual control of temperature not AUTOMATIC tempature control with a mind of its own. A cable mechanism will do it. This is an "UPGRADE" to automatic temperature control.

Karl

karlcchen · #10 (**permalink**) 10-16-2006, 09:18 AM

Another thing that is of upmost importance: even though thermostat is not open when engine is cold, coolant flow inside cylinder block maintained thru heater hoses and thru coolant reservoir at that time. Localized coolant inside cylinder block can boiled over in certain hot spot. So do not block the coolant flow ( to heater), it is not just for heater, it is used for coolant circulation too. It is ok to by-pass heater core with another hose.

Karl

Alfisto Steve · #11 (**permalink**) 10-16-2006, 09:20 AM

Point of information: Small coolant lines enter and exit throttle body from engine rear head to heater hose outlet that goes to heater core and from throttle body go back to coolant tank so small flow always present back to inlet of water pump from coolant tank lower outlet. You can stop water flow to heater core so no big deal. Besides, water circulates throughout engine in a closed loop fashion anyway until thermostat opens.

karlcchen · #12 (**permalink**) 10-16-2006, 09:30 AM

That's right. You should see coolant flowing out of small hose into reservoir when engine is running. The samll hose is also the highest point in cooling system, it is used to get rid of trapped air inisde the cooling system too, but not always working ferfectly. I think this kind of design is very typical of european cars of the era, US and Japanese cars are of different design.

Karl