DIY: mini fan belt R/R W210 turbodiesel
 

here's a brief pictorial covering the replacement of the mini-fan belt for the electric fan in front of the radiator. Subject car is a 1999 E300D. It's my understanding that this same design is found on some of the gas engine cars. It should be easy to visually identify. I can spin the right fan by hand and the left fan spins at the same time ;)

Written procedure courtesy of Matt L:


My picture numbering will correspond to the above text.


This job is quite simple. A few basic hand tools and two sockets are needed . I took this opportunity to clean up the A/C condensor and vacuum out a lot of bugs and stray leaves. I took my time (about 1 hour) and made everything nice, admired the amazing gaskets/seals/weather-stripping the Germans love to incorporate in their cars and condition rubber seals & mounting points.


Step 1. (two plastic tabs are rotated CCW 90 degrees. This light, plastic guard is lifted straight up and set aside)

http://img189.imageshack.us/img189/1940/plastabsdn7.jpg

Step 2. (two "M" shaped clips with rubber insert pull straight up and release top edge of radiator)

http://img175.imageshack.us/img175/2333/twoclipshc1.jpg

Step 3. (remove the 4 bolts atop the cross member. I just folded the sheet metal back and did not disconnect the hood release cable clip - - see lower foto)

http://img175.imageshack.us/img175/3...7screwsfu1.jpg

http://img326.imageshack.us/img326/9...bleclipuk6.jpg

Step 4. (You need to remove the power steering bolts, pictured below, before you can access the final bolt holding the bracket in the picture above)

http://img435.imageshack.us/img435/5946/psscrewszz5.jpg

Step 5. (remove 3 lower bolts, remove the bracket, the hood bumper and horn)

http://img175.imageshack.us/img175/3...7screwsfu1.jpg

http://img412.imageshack.us/img412/4011/hornpg7.jpg

Step 6. (remove the plastic cover and disconnect by squeezing the two tabs, pull cable off)

http://img435.imageshack.us/img435/5110/elecconnus8.jpg

Step 7. (once the two screws are removed, this fan assy will left up and out. I had to wiggle it around to get is passed the PS cooler lines.)

http://img349.imageshack.us/img349/6...nscrewszo8.jpg

here's the rear view of the assy once removed, it's fairly heavy.

http://img326.imageshack.us/img326/2...rmountsfo1.jpg

I made it a point to clean up all rubber mounts and used a rubber conditioner.


My belt was running inside out. It had burned its mirror image in the plastic shroud. I'm glad I checked this.

http://img483.imageshack.us/img483/2...dshrouddl3.jpg

Dirty:

http://img291.imageshack.us/img291/7964/dirtyradjt5.jpg

Clean :D :

http://img291.imageshack.us/img291/3194/cleanradzd1.jpg

Belt info:

http://img435.imageshack.us/img435/4677/beltpkgjp3.jpg

http://img126.imageshack.us/img126/1563/newbeltsvr6.jpg

While I have things apart I lubed points as necessary, condition rubber, used contact enhancer on the connectors and applied a little synthetic spray wax on painted surfaces that I don't normally have access to.

http://img502.imageshack.us/img502/7741/productsmb9.jpg

The rubber insulators within the "M" shaped clip were not in very good condition on this car - - they're always exposed to high temps. One was split in half. I've ordered a few new ones to do all the cars. They seem to be used across many model years.



(Belts were ordered thru Phil ($20 for two of them incl. shipping) and I had them next day. I ordered the 2nd belt to do another car this weekend.)

This is a good write-up. I've been talking to Tom about a slight change in the procedure that I used when I was wrenching, and Tom asked that I list the differences here.
The steps I would change a bit:
First remove the plastic cover as Tom has shown.
After that, remove the single bolt retaining the horn and small hood support bumper. (remove horn wires and set those aside, noting which was on top, the horn or the bracket)
Then remove the 2 screws holding the pipe (this is to cool the power steering fluid).
The pipe assembly can be pulled up slightly and then pulled forward and rested on top of the bumper cover. Use an old towel or what have you to prevent marking up the painted bumper surface. The 2 plastic clamps the 2 screws go through may shift a bit, they are easily reposition to where they need to be.
Next, below where the pipe was secured, in the center, remove the single bolt retaining the center of the radiator support, no need to unscrew the painted bolt up above where the horn was, you just make it look bad and no reason to remove it. Then take out the other 4 screws securing the radiator support and from there just follow Toms instructions.
A few other items I'd like to note:
Prior to cleaning the condensor, which you really should do, look it over for signs of an oil leak, this would be caused by a leaking condenser, the compressor oil will leak out along with the freon. This tells you it'll be time for a condensor soon, and a recharge.
When the front horn is removed, blow the horn to see if the other horn works OK or sounds weak, this tells you the other horn, the one under the right headlight, should be replaced. If you don't hear anything, you need a new horn.
There is also a rubber seal that seems to be missing on Toms car, it can hide the 2 bolts that secure the fan assembly. If you look through Toms pictures you will see the 2 sets of bolts I'm talking about, you need to remove the pair which are closest together, the wider pair are for the condenser.

Great work
 

A few more tweaks by both of you and it will be perfect for the DIY wiki page...:) :)

Yeah, it does need a little work. Gilly pointed out that my car is likely missing a piece of weather stripping on top of the radiator. I need to look into that. Also, I appreciate his comments on making a closer inspection of the A/C condensor for any apparent oil staining which will indicate a leak from the system - - that's a valuable tip.

Gilly also shared a slightly revised procedure which means taking apart one or two less (painted) bolts. So, if there's a better way to get the job done, I'm all for it.

:idea2:

This DIY is now in the Wiki
 

It's in the DIY Articles Wiki.

I guess the point on that one painted bolt is the lower bolt has to be removed anyways, so just take the whole support off in 1 piece. Just saves a step and the one painted bolt is left unscathed.
Gilly

Testing Fans
 

Is there a way to test the fan system after replacement of the belt. My car will not heat up enough to start the fans.

If you have the pushbutton unit for climate control, you can easily enter fan test mode.

With the key in position 2, press and hold both AUTO buttons for about 30 seconds, or until the fan starts at full speed. Holding both AUTO buttons for 30 seconds again leaves fan test mode, as does turning the key to position 0.

Weird design, they use a belt on the W210? Seems dumb.....if the belt fails you only have one fan, if the motor fails you have none. The dual motor design is way better IMHO. That is just another reason the W124 is better. :D

And that looks like a LOT more work to repair than just swapping one fan on a W126 or W124.

It's a bit more involved, but it only takes about 20 minutes to R&R the assembly. The single motor is very powerful and the belt seems to last a long time, so I don't really see a problem.

Unlike the 124 or 126 fan, the fan in the 210 is infinitely-variable in speed. It's not often running full-out, even with the AC running in hot weather.