Blower Fan Motor Replacement
09-11-2014, 04:07 PM
#47
Rennlist
Basic Site Sponsor
Basic Site Sponsor
So when your steering wheel is smoking, after your fan motor installation, you know who to call.
__________________
greg brown
714 879 9072
GregBBRD@aol.com
Semi-retired, as of Feb 1, 2023.
The days of free technical advice are over.
Free consultations will no longer be available.
Will still be in the shop, isolated and exclusively working on project cars, developmental work and products, engines and transmissions.
Have fun with your 928's people!
greg brown
714 879 9072
GregBBRD@aol.com
Semi-retired, as of Feb 1, 2023.
The days of free technical advice are over.
Free consultations will no longer be available.
Will still be in the shop, isolated and exclusively working on project cars, developmental work and products, engines and transmissions.
Have fun with your 928's people!
09-11-2014, 05:37 PM
#48
Advanced
Join Date: May 2011
Location: South Elgin, IL
Posts: 50
Likes: 0
Received 0 Likes
on
0 Posts
One more thing-- even though the instructions for placement of the cage on the shaft are clear, always power up the blower and check for rubbing before you button everything up...I didn't do that just so I could do a portion of the job twice......
09-11-2014, 09:09 PM
#49
Drifting
When I did mine I made the modification to the fan speed control resister pack to stop the "magic blower" syndrome. It has worked well. I don't turn the blower off completely. Keeping airflow through the resistor pack helps prevent the syndrome. Not sure if the 1990 has the same resistor pack as the early S4s.
09-11-2014, 09:17 PM
#50
I replaced a completely dead fan motor with Roger's new blower this Spring and have had great AC all summer.
The new fan motor is very quiet and the installation was very easy.
It is way too hot in Houston to have a crappy AC fan!!!
The new fan motor is very quiet and the installation was very easy.
It is way too hot in Houston to have a crappy AC fan!!!
Last edited by Jetdriver69; 09-11-2014 at 09:41 PM.
09-11-2014, 09:30 PM
#51
Rennlist Member
Just went new
When I did mine I made the modification to the fan speed control resister pack to stop the "magic blower" syndrome. It has worked well. I don't turn the blower off completely. Keeping airflow through the resistor pack helps prevent the syndrome. Not sure if the 1990 has the same resistor pack as the early S4s.
03-01-2015, 03:42 AM
#52
Archive Gatekeeper
Rennlist Member
Rennlist Member
Lest anyone wonder why the additional power supply harness is necessary for the blower motor upgrade: ~27 amps, steady state.
03-01-2015, 05:32 PM
#53
Electron Wrangler
Lifetime Rennlist
Member
Lifetime Rennlist
Member
Blower resistor pack changed to eliminate magic blower syndrome in 1989 (if it overheats it just turns off).
Alan
03-01-2015, 05:51 PM
#54
Basic Sponsor
Rennlist
Site Sponsor
Rennlist
Site Sponsor
Thread Starter
Alan & Rob,
I am electron challenged so go easy on me. IIRC the blower circuit is a 30amp circuit so if my new blower motor pulls 27amps is that not within the limits of the original circuit??
I am electron challenged so go easy on me. IIRC the blower circuit is a 30amp circuit so if my new blower motor pulls 27amps is that not within the limits of the original circuit??
__________________
Does it have the "Do It Yourself" manual transmission, or the superior "Fully Equipped by Porsche" Automatic Transmission? George Layton March 2014
928 Owners are ".....a secret sect of quietly assured Porsche pragmatists who in near anonymity appreciate the prodigious, easy going prowess of the 928."
Does it have the "Do It Yourself" manual transmission, or the superior "Fully Equipped by Porsche" Automatic Transmission?
George Layton March 2014928 Owners are ".....a secret sect of quietly assured Porsche pragmatists who in near anonymity appreciate the prodigious, easy going prowess of the 928."
03-01-2015, 08:48 PM
#56
Electron Wrangler
Lifetime Rennlist
Member
Lifetime Rennlist
Member
However it should be safe as in fuse won't blow & wiring won't actually melt, but the wiring/connectors are more stressed and you will be losing voltage at the motor (dropped over the wiring) so you will be missing some performance - the upgraded wiring is highly desirable for those reasons.
Alan
03-01-2015, 08:49 PM
#57
Electron Wrangler
Lifetime Rennlist
Member
Lifetime Rennlist
Member
03-01-2015, 08:55 PM
#58
Archive Gatekeeper
Rennlist Member
Rennlist Member
I have the old motor (out of the Cobalt car), will spin it up and see what kind of current it draws.
Whatever the current draw is, the new motor is powerful enough that it pneumatically roto-rooted the old, dusty evaporator and ductwork and blew dust and crap all over the newly refinished interior....
Whatever the current draw is, the new motor is powerful enough that it pneumatically roto-rooted the old, dusty evaporator and ductwork and blew dust and crap all over the newly refinished interior....
03-02-2015, 12:39 PM
#59
Rennlist Member
Edit:
I think having the motor inside the housing and blowing through the coil/ductwork will have and adverse effect on the motor amps. Now I can't remember if they go up or down.......
I think having the motor inside the housing and blowing through the coil/ductwork will have and adverse effect on the motor amps. Now I can't remember if they go up or down.......
03-02-2015, 12:52 PM
#60
Rennlist Member
Ok after some digging around, no static on the motor, will increase the motor RPM, thereby increasing the motor amps.
However, too much static above the original design will also increase motor amps....
So measuring the blower motor inside the housing, pushing though the coil/ductwork is the true way to measure the amp draw on these motors for our cars....measuring in the open air should produce a higher amp draw than "normal".
However, too much static above the original design will also increase motor amps....
So measuring the blower motor inside the housing, pushing though the coil/ductwork is the true way to measure the amp draw on these motors for our cars....measuring in the open air should produce a higher amp draw than "normal".