911SC defrost dial

s_wilwerding · s_wilwerding's Garage

I just bought an '81 911SC - my first Porsche. The previous owner had somehow managed to break (it now spins freely) the defrost dial located on the console between the front seats. In some attempt to fix up the car, I would like to replace the dial. However, I cannot seem to find the appropriate part.

Can anyone help me? Has anyone else had this problem?

Thanks.

Jdub · 06-17-2002, 09:46 AM

It may go deeper than a fresh dial. The dial activates a cable that opens or closes a vent under your car. That vent, when open, exhausts hot air to atmosphere. Closed, you get the hot air in the cabin.

If the dial won't move, *maybe* the cable(s) are frozen at the vent box? It would make sense to manually activate the vents to determine if you have frozen cables.

Then again, maybe the dial just broke! It can't hurt to have a consenting independent mech. put it on a lift for a six-pack and give you the benefit of their experience.

John

island911 · 06-17-2002, 10:31 AM

Quote:

Originally posted by s_wilwerding
. . .the defrost dial located on the console between the front seats. . . .

Where?

A, B or C ?

Jdub · 06-17-2002, 10:37 AM

Island and '81:

Isn't this the dial facing up between the seats, where you might find the "old" hand-operated levers?

If not, forget everything I wrote above!!

John

s_wilwerding · s_wilwerding's Garage

It's even further back than shown in the picture. There's the hand brake and heater control on the floor and behind that, on the console between the seats (like where an armrest would be), there is a defrost dial. Is this something unique to the Euro models?

Thanks for all your help.

island911 · 06-17-2002, 11:07 AM

Quote:

Originally posted by Jdub
. . .Isn't this the dial facing up between the seats, where you might find the "old" hand-operated levers?
John

Ah, right . . .the "climate control" box.
You guys with your plush cars.

steve911 · steve911's Garage

Are you sure its a defrost dial? On my '85, it is a 3 position switch for controlling the heater fan, not the defroster.

Jdub · 06-17-2002, 11:50 AM

Hey buddy, you are talking to a window rollupping, heater lever pulling fool over here so show some respect!

Heck, even my valve gear clearances require manual updates...

Har har,
John

rfix'n · 06-17-2002, 12:18 PM

I have the "plush" auto heat, if your dial just spins and there is no corresponding change in the red lever than your auto heat is broken. If this is the case, chances are someone pulled / pushed the red lever (a no no with auto heat) and broke the mechanism inside. Not sure if parts are available for the climate control box or if you have to purchase a whole new box. I think most people convert to manual heat when this happens.

Bill Douglas · 06-17-2002, 02:37 PM

Most of those things don't work. If you do want to have a go at getting it going pull the cover off and find exactly what is wrong. There are also little polyurathane ball in socket things that fall out plus the little motor may not go either. Also there is a temperature reader sensor by the rear view mirror that may not work either.

On my car, a '79SC, all of the above were knackered so I just use the levers. Much better.

I'm thinking off pulling the guts out of the heater dial box so I can cut a big hole in the top to use it as a coke can holder. Good idea?

Doug E · 06-17-2002, 05:59 PM

I didn't know that control box was available in '81. On mine there are just levers.

BTW, welcome to the wonderful world of 911 ownership!

speeder · speeder's Garage

The dial you are refering to is the optional automatic heating control that was available in 1981. I have it on my '82 SC. If dial spins freely, there is a SLIGHT chance that knob is stripped and can be replaced. Not sure, but even that might be a junk-yard only item, the climate-control is sold as a complete unit, dealer only, price including Porsche tax is approx. $1200.00.

The way to simply bypass it is to remove tiny bolt that connects heater lever, (with red knob), to auto-control. Then you can use lever manually as though auto-control was not there, only catch is that heater blower-fan in engine compartment is wired to auto-control, will not go on when you raise lever as it is supposed to. Fan is not really neccesary, but it does kick some extra ass when it's really cold or windows are fogged badly. If your auto-control is broken in the full-on position, (as mine is), and fan is not dis-connected it is probably fried anyways. Good luck.