[dancing__narwhal]

I've been getting frequent rattle from my HVAC fan lately. It seems most pronounced with the fan in lower speeds. It definitely is aggravated when braking or turning, likely due to the lateral forces put on the fan.

Has anyone run into this before? Is my blower motor going bad or can I just lubricate the fan somehow?

Thanks in advance!

[MysticRob]

http://lmgtfy.com/?q=bmw+hvac+fan+squeal

[dancing__narwhal]

Originally Posted by MysticRob

http://lmgtfy.com/?q=bmw+hvac+fan+squeal

To be fair, I did several searches here on e90post and couldn't find anything relevant. But, alas I didn't think to check google for other forums!

[tlow98]

You can lubricate from above through the cabin filter hole under the hood. Get a small diameter tube and squirt some lube down onto the center of the squirrel cage. Takes about 15 mins

[MysticRob]

Originally Posted by N52 E90

To be fair, I did several searches here on e90post and couldn't find anything relevant. But, alas I didn't think to check google for other forums!

As part of that search you'll see tons of youtube vids if you need visual walk-thru on procedure.

[Efthreeoh]

Search the DIY section for "HVAC Blower Motor Replacement", which was a DIY I published in 2010. I've replaced my blower motor twice now. IMO you can try to lube the bearing via opening the cowling by removing the cabin airfilter, but it's not a long term solution. You'll see a part that looks rusty, but it is only the press fitting that secures the fan blade to the motor shaft. The only way to get near either bearing is to remove the blower motor. The top bearing is hidden by the fan blade, the bottom bearing is under a cover.

The blower is just a bad design. The motor shaft is oriented vertically, so any moisture on the shaft just flows right into the bearings. The bearings rust, then wear out.

IMO once the blower makes noise as you described, you might as well replace it. Good news is the OEM, Valeo, now sells the aftermarket version with a new resistor pack, for around $100.

Considering the blower motor assembly is under recall, maybe you should wait and see if BMW will replace it as part of the recall. If not, then I recommend replacing the blower motor, because it will eventually wear out.

[dancing__narwhal]

Originally Posted by Efthreeoh

Considering the blower motor assembly is under recall, maybe you should wait and see if BMW will replace it as part of the recall. If not, then I recommend replacing the blower motor, because it will eventually wear out.

I was wondering about this too. Seems like it might be a while before they get around to these replacements though...

[Efthreeoh]

Originally Posted by N52 E90

I was wondering about this too. Seems like it might be a while before they get around to these replacements though...

If it just starting to make noise, it will go months if not a year before it totally fails. My second blower motor started clicking and it took a year to get intolerable. I drive my car at least 20 hours a week.

[dancing__narwhal]

Originally Posted by Efthreeoh

If it just starting to make noise, it will go months if not a year before it totally fails. My second blower motor started clicking and it took a year to get intolerable. I drive my car at least 20 hours a week.

Good to know. It's not too bad at this point, which is why I was wondering if I could just lubricate it.

I'm doing plugs and coils this weekend. Since i will have the cowling pulled off anyway I'll try lubrication and see how it goes.

Any recommendations on what to use? Wd-40, silicone lube, something else...?

[mecheng77]

The recall is for wiring not the fan.

Wd40 should not be used. Use a oil for electric motors like your furnace. If in a bind put some motor oil in an oiler and use it. I also put some grease after the oil so it doesn't dry out

[Tim_354841]

Careful with the oiling. Oil has VOCs. I had headaches after oiling mine. $125 replacement + an hour of work isn't bad (easy repair), but it's worse if you have to clean oil off the chamber walls where the fan lives (I did). Diluted Dawn detergent worked perfectly

[dsjr2006]

Haven't replaced mine yet, but I have a similar issue. I've tried using lube before on a different vehicle and the smell was awful. I'll be buying the fan with a warranty since it seems poorly made and I plan on keeping the vehicle for awhile.

[BimmerNugget]

Originally Posted by MysticRob

http://lmgtfy.com/?q=bmw+hvac+fan+squeal

[Efthreeoh]

Originally Posted by dsjr2006

Haven't replaced mine yet, but I have a similar issue. I've tried using lube before on a different vehicle and the smell was awful. I'll be buying the fan with a warranty since it seems poorly made and I plan on keeping the vehicle for awhile.

I think the fan is made pretty well, the issue is the vertical orientation of the shaft. It's a stupid design for longevity.

[dsjr2006]

Originally Posted by Efthreeoh

I think the fan is made pretty well, the issue is the vertical orientation of the shaft. It's a stupid design for longevity.

We’ll have to agree to disagree then. Presumably they knew the orientation of it when designing it and it couldn’t even make it to 70,000 miles. My E39 has a horizontal fan and that’s not known for its longevity either.

[dancing__narwhal]

Last weekend I bought one of those aerosol HVAC cleaner sprays and sprayed in straight into the blower fans with the air filter removed. Ever since then the noise has gone away so fingers crossed the motors last a while longer