W202 heater fan noise & vibration??? - PeachParts Mercedes-Benz Forum

MarkC · #1 01-14-2005, 01:22 PM

While looking at purchasing a used 1998 C280 with 73K miles I noticed that the heater fan would emit a vibration noise from position 3 (on the digi display) and get worse as the fan speed was increased. It was almost like a thumping, or shuttering vibration noise. Any idea what this could be except for 'expensive' (remove dash and replace fan etc.)? Should I avoid this car and look elsewhere?

Thank, MarkC

mpolli · #2 01-14-2005, 01:28 PM

I believe there was a TSB concerning excissive fan noise which was caused by a clogged cabin filter. Not sure if that would help your problem however. Hopefully someone else has something more to add.

Mike

benzfan · #3 01-14-2005, 02:22 PM

The dash does not need to come out for a fan replacement in a 202. It takes about 15min to do even if you have never done it before.

http://mbclub.co.uk/forums/showthread.php?t=3593

Bear in mind that this link was from a UK site, so everything appears mirror imaged in the photos (RH drive and all...).

benzfan · #4 01-14-2005, 02:26 PM

If the person you're buying it from is not familiar with the 202, use the noisy fan and the possibility of dash removal to lower the price of the car, knowing that you can do the job yourself quickly and cheaply.

MarkC · #5 01-15-2005, 10:14 AM

Thanks for the replies

The link to the pictorial fan-replacement tutorial is very informative

, and will come in handy if the cabin-air filter is not the cause of the noise/vibration.

Thanks

Ali Al-Chalabi · #6 01-15-2005, 11:06 AM

The recommended replacement interval for the cabin filter is every 15k miles according to the book. If you use the climate control a lot it can become pretty dirty within a year or so.

benzfan · #7 01-15-2005, 03:01 PM

Yes, it can get very dirty in a hurry. And when you replace it, the difference in your A/C airflow on a hot day is astounding. The whole system is so much more efficient.

MarkC · #8 07-13-2005, 09:22 AM

I did buy this car and yesterday I finally solved the problem. After replacing the cabin air filter with no improvement, I decided I would order a new blower motor.

But before ordering, I decided to remove the fan motor to see perhaps if it may just be excessively dirty and to inspect the mounting etc. I discovered a piece of plastic (pen cap sized) sitting in the fan basket. It looks to be from the end of a round tube of silicon caulking (the piece that gets cut off).

That rogue piece of plastic was responsible for the vibration in the dash, steering wheel and even floor, and now removed, the blower motor spins smooth and builds revs quicker from 'off' to 'max' than ever before.

So the lesson; Remove the blower motor for a thorough inspection before buying a new one.

MarkC

mpolli · #9 08-20-2008, 02:20 PM

Fan started making some noise today. Can worn brushes cause noise or would the fan just stop or run poorly? Actually it sounds like some debris in it. Is the fan before or after the cabin filter?

jlomon · #10 08-21-2008, 08:56 AM

Quote:

Originally Posted by mpolli

Fan started making some noise today. Can worn brushes cause noise or would the fan just stop or run poorly? Actually it sounds like some debris in it. Is the fan before or after the cabin filter?

The fan is before the cabin filter and is quite susceptible to debris getting in there. I've removed mine before to clean it out when it got noisy and found a bunch of dried leaves, etc. Its a simple job. You'll be surprised what comes out.

slk230red · #11 08-21-2008, 10:06 AM

Quote:

Originally Posted by mpolli

Fan started making some noise today. Can worn brushes cause noise or would the fan just stop or run poorly? Actually it sounds like some debris in it. Is the fan before or after the cabin filter?

I found 1 small leaf in mine some time ago and it made a loud squealing noise.
Removed it and it has been quiet since.