Fuse #25 auxiliary fan

[tsmcg161]

My original auxiliary fan started making noise so I decided to replace it. I purchased one from Worldpac, a VDO "OEM", and installed it. At high speed the vibration was so bad the steering wheel would shake, so I got another one. I installed the second one and still the same vibration. Now im unhappy because this job requires sliding the front bumper back a few inches. So I got a third one and again same vibration. My time is very limited and doing the same job this many times really pisses me off. Found one at my local junkyard from a donor 91 750il and installed it. No vibration at any speed yet, it keeps blowing fuse #25 after running a couple of days. Its a 100 degrees here in south Texas. Some of the 30 amp fuses got so hot they melted in the fuse block before popping. I took the aux fan apart and cleaned the motor as best as i could. I ran it yesterday about 10 miles and pulled over to check fuse. It wasnt blown but, it was too hot to touch. My next try is to replace the resistor on the fan itself. The switch on the radiator is new. Any ideas or experience would be very appreciated.

[htrdbmr]

I would look for loose/corroded wiring connections, don't forget the ground point

[unity]

Odd. Honestly my first thought is the fan was installed wrong. Three bad fans is not likely. There are three mount points for the fan and the bolts only need to be backed off for the fan to slide into the holders which are rubber. And as for the factory fan, it may not be spinning up as fast as the new ones and why there is no vibration.

FYI, when I replaced mine I raised the front of the car and removed the fan access panel from the bumper at lower center. Tight fit but I found no need to actually remove the bumper. Only part that annoyed me was the upper most mounting location. But I have had to do much harder projects on this thing.

[tsmcg161]

Little bit of progress with this overheating #25 fuse. Again it gets so hot its melting the fuse block and its too hot to touch. I got rid of the junkyard BMW OEM aux fan and replaced it with a TYC brand this time. Fuse #25 is no longer scalding hot but, the fan vibrates horribly at low. Its so bad the steering wheel shakes. Im now up to 3 VDO fans, 1 old junkyard fan,that doesnt vibrate, and now this TYC. All connecting points at the condensor are fine. Its obvious to me that the fan blades are not balanced. OE BMW fan is 500.00 bucks. Thats a big difference versus aftermarket. Any multiple fan replacement experts out there?

[shogun]

About 10 years ago I replaced my aux fan because on the old one the magnets in the motor got lose and that jammed the motor = fuse melted, that is the basic problem with the old fans.
autohausaz has on sale for $157 64541392913 incl. free shipping Continental VDO - Auxiliary Cooling Fan Assembly, List: $602.74

[E32FAN]

You could test the fan for smooth, vibration-free rotation before installing it.

Just jumper its terminals to 12V.

[tsmcg161]

So not securing the fan would be considered an accurate test?

[shogun]

I have tested some used fans without installation, just with a 12 volt battery.

[tsmcg161]

Problem solved. Got a new BMW fan that's smooth as silk on both speeds. Fuse #25 doesn't get scalding hot anymore either. Tried to save money with after market and junkyard items. It just didn't work this time.