124 aux fan replacement
 

Would the procedure on the 104 motor be much different? Such as removing the right headlight assembly? Thanks for the very detailed description of the process. Good to know it can be done without disconnecting hoses such as the a/c. As I read this the radiator doesn't have to be moved. It's all done out of the front of the radiator. Right?

Al

1988 300E aux fan replacement
 

Does anyone have any comments on the differences or a procedure for a 1988 300E aux fan replacement? My dealer wants to charge me 600+ to do this job.

Be sure to check rotation on the new fan prior to putting everything back together. I did this job on my 95 E320, it is possible to do without removing the bumper or radiator/condensor. The trick is to remove the upper radiator retaining clips and then tilt the assembly in towards the front of the engine. You may have to disconnect the upper radiator hose to allow enought tilt. The tilt will allow you to wiggle the plastic hole housing around the front of the fan bullets. The first time I did this job it took about 2 hours. I did it again in about an hour the second time to correct the fan rotation problem. (doh) Believe it or not, the incorrect rotation direction has been reported by several other forum members.

That is spot on advice..the fan motors fit other makes and they can come NEW phased out of polarity, requiring swapping of the power leads polarity for direction change.
The fan hub has a direction indicator arrow embossed on it to verify proper direction requirements for your chassis.

I did replacement job with removing bumper and passenger headlight assembly, just to get more space for my fat fingers. Pick and pull fan was used. Can anyone post a picture of a resistor, please. I still can't found one. thanks!

On the 126 the ballast for the aux fan is under the brake master cylinder mounted between the two firewalls

on a W124 its besides the A/C dryer behind the driver side headlamp, the later ones with twin fans have a larger sized one while the early ones have the smaller one.

If you do have a W126 with the resistor under the brake MC - move it out of there as soon as possible.

This might help:

http://www.peachparts.com/shopforum/tech-help/294766-auxiliary-fan-failure-analysis-used-part-request.html

Yeah, it's a 190, but the 190 is just a 7/8 scale 300.

There should be no need to mess with the radiator or condenser. The fan shroud needs to come off so you can remove the upper radiator/condenser support.

Definitely take off the bumper, at least to reinstall the fan frame. It's easy and only takes a few minutes and will save you a bunch trying to remove/install the radial fan frame mounting screws. They can be removed with the bumper in place, but it's impossible to get them started with the bumper on. Don't risk striping the threads in the aluminum fan frame.

Note that you remove the entire frame that holds the fans. Then you can easily remove the individual fans from the frame.

Duke