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-   -   How to remove whirring sound from 993 dash (

geolab 05-20-2007 05:41 AM

How to remove whirring sound from 993 dash
Tools needed:
small pliers- philips small screwdriver- graphite grease (or any hard grease)- optional blaupunkt radio removal plug.

One of the HABITUAL phenomenas that 993 owners encounter is the whirring in the dash, some has it some don't.
Some owners attribute the noise to the clock mechanism, others search the 993 forum and deduce its their Climate Control Unit's temperature fan, which it is.
Personally, I always thought that hearing the noise after removing the keys from the contact, meant the CCU was well functioning, until the noise became loud and irritating.
To remove the noise, I pulled out the CCU.
To do so, two options:
-either you get two blaupunkt radio removal plugs, plug them in the CCU holes on each side, and pull the unit out, or,
- you reach behind the CCU from under the dash, and push out the unit.
make sure your wipers control arm is up to max position, not to interfere with the CCU getting out.
Once the CCU is out, un-plug the two electric harness plugs inserted in the back, no worries which plug to re-plug in which socket, they come in 2 different sizes.
Now you can see a small fan mechanism, hanging in the back at an angle, this is the culprit.
To remove, unplug the electric socket that goes out of the small fan into the CCU's back.
With a pair of small pliers, unscrew the two yellow 6mm nuts that hold the fan mechanism to the CCU's back.
Now gently, pull the fan mechanism out of the CCU's back. It is hooked through a small rubber tube to the inside of the unit.
Now on the top of the Fan mechanism, you can see that the whole part holds together with two screws from the top.
Unscrew these two screws, and take care not to loose the two nuts holding the mechanism together, these nuts can be taken out sideways on the mechanism.
Now open the fan mechanism like you open a small box.
you will find the fan resting inside. take the fan out.
Do not worry for small pieces to fall out, there is none.
The way I proceeded, I sprayed brake cleaner on the three pieces, the fan and two housings, and dryed the pieces with compressed air. those were clean now.
Now put an infinitely small grain of grease on the tip of your finger and smear it with your thumb.
With your finger, wipe the sides of the fan housing (both pieces), and the ouside circumference tip of the small plastic fan. Do NOT smear the plastic with grease. No grease should be visible, just the plastic should look darker.
Now take the fan in one hand, and grease both sides of the axle tips, with the tip of a match. Just put a grain of grease on the needle nose tip of the axle.
On the housings, put a grain of grease in the center holes where the fan axle sits, again with the tip of a wooden match.
Now seat the small fan in the bottom housing, and close the housing with the top part.
Reassemble the housing chassis and tighten the srews.
When the fan mechanism is ready and assembled, spray some air on the fan to make it turn swiftly and to check that it circles freely.
re-mount the fan mechanism on the back of the CCU with the small brassy screws, and insert the electrical plug in the back of the CCU.
Now that all is assembled, hook the CCU to the plugs in the car, and before inserting it in the dash, put the car contact on with the keys, and check that the fan turns. Once you do that, put the contact off, and insert the CCU in the dash.
VOILA, no more whirring...

Land Jet 05-20-2007 12:16 PM

geolab, many thanks for this. I have heard this sound for a long time, although not loud, it was mystifying. Eventually I will have to do this exact procedure.
One question please; are you a Porsche mechanic or just a great enthusiast? I have followed your many posts on the forum and all of them are spot on. Also I saw you publish material from the dealer many times. Just trying to understand where your expertise comes from. Thanks again, you are a great resource. :cool: :biggulp:

TomF 05-20-2007 12:33 PM

Thanks for the writeup. As of now, my CCU fan is quiet, but I am certain it will become noisy at some time and this will be very helpful.

Avid Fan 07-01-2007 11:10 AM

Thanks geolab. The noise in my car is very loud and obnoxious. I'll be taking care of this today.

ecobb993 07-31-2007 05:07 PM

I had this noise, but it has gone away on it's own. Is this a good thing? Or an indication of another problem?

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