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924RACR

So my 931 sat over the winter (imagine that), and I think some water worked its way in due to heavy Dec. rains, probably got at the under-dash grounds and fusebox... so now I've got the independant intermittent wipers again, plus my AC won't turn on (not even the fan)... ARRGH! To top it off, my blower fan (for heat and defrost) has kicked the bucket, seems like terminal failure (open circuit, and some bits look cooked).

So once again the only ventilation in my car is the windows, and I'm going to have to take the dash all out and swap in another fan motor. Hope I have a half-decent one laying around. I guess partly I hate doing all that when I know that even after all that work, it still won't exactly blow my hat off! But I've gotta have some ventilation, and those wipers are really embarrasing on a dry day. I mean hey, I drive the car cause it's fun, not because it's got al the electronic doodads, but simple crap like that...

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Vaughan Scott
Webmeister
'79 924 #77 SCCA H Prod racecar
'82 931 Plat. Silver
#25 Hidari Firefly P2 sports prototype

Tigger937

924RACR · Posted: Fri Apr 28, 2006 2:46 am Post subject:

LOL... yeah, I checked the relay already - so will have to get serious w/ the multimeter and wiring diagram, figure out what's missing.

Yes, the blower motor is accessible, but not removable (except maybe the '82-built cars; mine was built in '81, though titled as an '82), from underhood. I'll have to remove the R2D2 (HVAC) unit) and split it to get the motor out. Major overhaul. But I have to replace that R2D2 anyway, as the linkage for the fresh air flap is broken anyway. Already have a replacement.

On the plus side, my fabricator works at Bosch down the street in the body electronics division; he said he's got "squirrel cage" type blowers all over the place down there, and we can look at retrofitting one. I'll try and take pics, so hopefully we can try to share the procedure if it's not too bad, so others can do the same...
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Vaughan Scott
Webmeister
'79 924 #77 SCCA H Prod racecar
'82 931 Plat. Silver
#25 Hidari Firefly P2 sports prototype

Tigger937 · Posted: Fri Apr 28, 2006 4:39 am Post subject:

das push · Joined: 27 Oct 2005 Posts: 53 Location: cincy, oh, usa

for the blower check the switch. the reason I say this is the wipers, brake lights, and the blower(heat/defrost) circuit run thru the switch. If you pull the switch you will lose all three.

now for a question to others for a little help with my blower. IIRC there is a resistor in the harness for the blower. If I'm correct does anyone know what I show for(value) resistance. I have continuity; blower runs if directly hooked up to an external power source but not through the harness. switch is new and functioning.
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1982 924 NA 85K owned since 1992
82 nicknamed das push"the push"by my kids.
lots of electrical problems 1st yr of owner ship!

Ozzie · Posted: Sat Apr 29, 2006 6:20 pm Post subject:

I have had 3 cars where the resistor box for the fan has died.
I managed to repair 2 but replaced 1.
Don't know the values though.
The units had got so hot the solder had separated.
(fans were tight but were greased before finishing the job)
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Porsche 924 1984 (UK import) NA
Its AUTO and its BLACK
Montego Black on black/red
Engineer of Electro/Mechanical Systems Maintenance

Tigger937 · Last edited by Tigger937 on Sun Apr 30, 2006 2:05 am; edited 4 times in total

924RACR · Posted: Sun Apr 30, 2006 12:12 am Post subject:

From memory, since I did check this of course (remember, I wrote the book on diagnosing electrical problems in these cars), I found 0-1 ohms on the full-on position (measured at the fan connection, between the ground wire and actual ground - remember that the fan grounds through the switch, and gets 12V as long as ignition is on). In the Low position (marked "I"), I found about 3-4 Ohms. Below that, in the variable section, it goes up to, as I recall about 30-40 Ohms.
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Vaughan Scott
Webmeister
'79 924 #77 SCCA H Prod racecar
'82 931 Plat. Silver
#25 Hidari Firefly P2 sports prototype

Tigger937 · Posted: Sun Apr 30, 2006 4:03 am Post subject:

Stampedetrail · Joined: 29 May 2005 Posts: 274 Location: Fairbanks, Alaska

Fan motors often go belly up for whatever reason. Mine was not included. The one on it is from a VW jetta. I had to create a shroud for it, but I'd rather not discuss how that was accomplished. I'd start with ripping the fan motor out from the hood, not the dash, and find a good Bosch motor. One switch- on full blast or off.
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1977.5 924 "Martini" head / New Old Stock rebuild
1985.5 944 Why? Because I can.

924RACR · Posted: Mon May 01, 2006 9:56 pm Post subject:

Sure, but this car is primarily a restoration car, to be kept stock. If I wanted power, I'd rig up a 12V ducted fan from a marine supply store - sold as a bilge vent fan. Those things pump serious air, are efficient, and compact. I'll eventually get around to installing one of those in the racecar (which, ironically, has a stock fan that works well).

Tightened the screws on the wiper switch - they were indeed loose, and I think that may fix my wiper problem. Unfortunately, I really need to replace the lock housing, as 2 of the 3 screw holes are stripped (explaining why they come loose). Also causes problems getting the high beams to work - since the whole housing moves when you make that motion.

Still haven't dug into the AC problem, but I have to go racing this weekend - will worry about that later...
_________________
Vaughan Scott
Webmeister
'79 924 #77 SCCA H Prod racecar
'82 931 Plat. Silver
#25 Hidari Firefly P2 sports prototype

Smoothie · Posted: Mon May 01, 2006 11:55 pm Post subject:

You might get some more life out of the lock housing by re-tapping the screw holes. I did it (very carefully) - tapped to the next larger standard screw size and that's how mine's put together now. If you don't want to do it, send me your old one when you replace it!

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"..it's made in Germany. You know the Germans always make good stuff."

'82 924T, US version, dark green metallic, 5 speed Audi 016G gearbox

924RACR · Posted: Tue May 02, 2006 12:10 am Post subject:

Not a bad idea...
_________________
Vaughan Scott
Webmeister
'79 924 #77 SCCA H Prod racecar
'82 931 Plat. Silver
#25 Hidari Firefly P2 sports prototype

Stampedetrail · Joined: 29 May 2005 Posts: 274 Location: Fairbanks, Alaska

924RACR · Posted: Tue May 02, 2006 10:21 pm Post subject:

Unfortunately, that's not an option; the dash can no longer be removed from the racecar, due to the dash bar install - it'd have to be cut out. Or, at very least, I carve out the fan from the box via underhood access (not ready to do that yet).

Thankfully, the wipers stay put now that the screws are tight! Not so embarrassing to drive any more...
_________________
Vaughan Scott
Webmeister
'79 924 #77 SCCA H Prod racecar
'82 931 Plat. Silver
#25 Hidari Firefly P2 sports prototype