sticking air flow control

[bsg]

Has anyone found a cure for the sticking air flow control?
I have heard that a couple of screws in the airflow controlbox on the right spots might help, anyone that knows anymore about this? (2 toiletrollholders broken so far)

[Kolhoznik]

I'm working on doing the screw fix. If only it wasn't so damn cold outside. I should be done in a week or two and will do a writeup.

[bsg]

how do you know where to put the screws? have googled it , but no luck

[Kolhoznik]

In my own thread about this issue one of the members that has done it gave me the info. Basically you have to remove the passenger vent tube to get access to that part of the drum.

[bsg]

ok . found the thread!

thanks!


( http://www.saabcentral.com/forums/sh...ad.php?t=92064 )

[Kolhoznik]

Let me know if you do it before me. I still don't see the clear way of removing that duct.

[bsg]

its realy cold here too, but I will look intoit this weekend , I will keep you updated..


Update: do NOT place a screw in that position!
it will obstruct the movement of the lever that controls the heat/cold

I will update with pictures and more later today...

[bsg]

ok, glove-box and side panel out, vent-tube still in place:



vent-tube out, looking into the drum:




The lever in the background moves behind the opening (hot/cold air) so its not a good idea to mount a screw hereas it will obstruct the movement of the arm. :



inside the sylinder, (between cylinder and drum ) there is some black, tarlike goo. its like rubber, but has obviously been a fluid when the heater is running at max, it has been running down in the corner (picture above)
a droplet can be seen in the picture below. :



carefully bending the drum and cylinder apart shows that the residue/tar/whatever-it-is is stuck there too.




I tried to remove the tar-stuff, but its realy hard and rubbberlike, i guess that when this gets hot it will get fluidly and stick things together when cold.
bending the cover over the drum outwards did not make it run more freely, so the screw-fix have to wait until I get all the "tar" out. I still havent opened the other side, it might be just as bad there

I will be back with more later...

[Old Goat]

Seems like a fun repair to do when its cold outside. Great pix.

[Kolhoznik]

LOL...I came in here to warn you not to put a screw in there, but been beat:-D Just came back from working on it. Now if you do PULL on the part behind which the temp control lever is it DOES make it easy to turn the drum. So I'm planning to drill a hole in that tab in which the screw is shown in the diagram and than use a T-hook and some wire to pull ot a bit to the pass side. that should free it up enough for the drum to move without having to break the toilet paper holder. Thats a nice project for tomorrow morning.P.s. my pics are dark...yours are much better, so I'm not even going to bother posting them.

[bsg]

did you see any tar-like residue in there?

[earthworm]

The quality of the digital camera pics has reached a new high.

This is where even the very best of manuals fall short....
Maybe this black sticky substance is the crux of the problem. The Saab engineers had best be paying attention here..

[Kolhoznik]

I've found some yellow brick-crumb type of stuff in there, however it isn't the problem. I used dielectric grease in there and it didn't fix a damn thing. However pulling on either the top vent outlet or the borrom vent outlet DID free up the drum. I think I will rivet (a screw will most likely become loose) a metal hook on the bottom vent and than will probably use wire to pull on the vent. We'll see next weekend.

[Kolhoznik]

Any chance that the screw fix was intended for the driver's side of the box?

[liketheword]

Originally Posted by earthworm

The quality of the digital camera pics has reached a new high.

I would say so! Look @ the particals of dust.

Also, is this suposed to be a regularly serviced item?

[Kolhoznik]

not really supposed to be, but this is a known problem. Even my mitchell repair manual has an article on this.

[bsg]

I tried to access the drivers-side of the box, but gave it up.

I sanded down a bit of the box, where the box and the drum was touching.
then I used a wooden wedge to pry the box a bit backwards.
the whole thing moves easier, easy enough to feel the notches of the button. (witch I never knew was there before)

[Kolhoznik]

There's notches on the thing? Damn, now I have something to look forward to:-D But I think I'll need another toilet paper holder cause this one is already sloppy.

[mur]

bsg, exactly where did you sand down? Ive pryed mine around a bit, but I can't find exactly where the friction is. Also, I am thinking about lubing this whole thing up, does anyone know what the best thing to use would be, I am afraid of using grease, because I fear that it will lose its effectiveness in the cold.

Thanks, Mur

[dabrig]

I had the sticking drum problem several years ago. After replacing the "toilet roll holder," I sprayed food grade silicone spray lubricant into the heater box, soaking everything as best I could. This is a very low-viscosity aerosol lube that I originally purchased for the fill-port o-ring on my old water softener. It worked wonders. The system has worked fine since, but I make a point of not casually spinning the heater control knob around unnecessarily. I always move it rather slowly and deliberately, feeling the drum turn as I go. It's a very poorly designed system, in my opinion. Even if the drum didn't stick, that's a fair amount of rotating mass being moved by the flimsy mechanism, and flicking the knob around would probably cause eventual failure even if nothing was actually sticking.