300 E Auxiliary Cooling Fan - PeachParts Mercedes-Benz Forum

tino · #1 06-26-2007, 11:41 AM

The auxiliary fan in my 1986 300E stopped working - causing the AC to cut out when I most need it in rush hour traffic -- there is power to the fan so it seems the fan is cooked - -- before I buy a new fan I would like to remove the assembly and check the fan brushes etc. can someone please tell me how and what's involved to re and re this fan assembly .
Tino

david s poole · #2 06-26-2007, 11:47 AM

have you removed the wiring from the plug[behind the left headlight] and fed 12v.directly to it?the low speed fan is used for ac and this power goes through a large resistor down by the headlight.the resistor can fail and the wire connections can fail also.

tino · #3 06-26-2007, 01:52 PM

Thanks for response - Yes I have put power to the fan plug but nothing happened - where is this resistor and can I by pass it?

865sp300e · #4 06-26-2007, 02:55 PM

The resistor is mounted flat on the frame in the area aft of the left (driver's side) headlight. Pretty tough to miss.

Arthur Dalton · #5 06-26-2007, 03:00 PM

If you have power to the fan plug , you do not have a problem with the resistor ..the plug is downstream from the resistor circuit.

JimF · #6 06-27-2007, 10:37 AM

Take a 'hammer' and give the front of the fan(s) a 'tap'. . . if it's brushes, it may start up. . .

tino · #7 06-27-2007, 06:58 PM

Tapped the fan with a hammer and it worked for a few minutes -- Removed fan assembly and took it apart - the brushes were like new however the bearings were very tight - cleaned - greased and re installed and all seems fine now - Just one point -- had problems removing the center fan nut until I realized it has reverse thread --

JimF · #8 06-27-2007, 07:08 PM

Good job . . saved a few $$$ . . glad it showed you what to do next.

Arthur Dalton · #9 06-27-2007, 07:47 PM

< __________________
>>

Very common to have CW rotational parts have reverse threaded shafts ..otherwise they would simply unthread themselves, specially at start-up.

tino · #10 06-27-2007, 08:56 PM

Thanks to all --