When I turn the heater fan on it makes horrible noises.

[e30BMart]

A huge rattling sound is made when I turn on the heater fan. What could it be and how do I fix it? thanks!

[Quadrajet]

It could be one of the blades on the squirrel cage has broken loose from the wheel and it's rubbing on the housing.

[Nsquared97]

http://e30.bmwdiy.info/blower-resistor/index.html

[Click]

Yeah my fan buzzes in a fashion that I would think a blade has come partially undone. Turning my fan on speed 2 or higher makes it go away. Making a right turn makes it louder as well.

[mikeedler]

just changed out my fan motor last week, there was nothing left of the bushings! Made the same noises as yours.

[accident]

I had one half of the blower fan explode in to pieces once. Unbalanced the whole assembly, made horrible noises when the fan was on. I thought my motor was fucked when it first happened and shut the car down. I didn't figure out that it was the fan until I turned the key on to restart it and the noise started again immediately after I turned it on, before I even started it.

^ Cool story bro.

[Raxe]

Need a new blower motor assembly.

[e30BMart]

I can't find a writeup for removing m42 blower fans. Every site I look at doesn't look at all like what I have. (1991 318is) No ac if that changes anything

[e30BMart]

I took the blower motor out and oiled it up. The bushings are finished so it still makes noise.. Probably gonna break someday Ill need to change it.

[Click]

What are the bushings like on these motors? Would it be possible to turn some new ones on a lathe and repair it? I see they are like $300+ new.

[kts]

What are the bushings like on these motors? Would it be possible to turn some new ones on a lathe and repair it? I see they are like $300+ new.

Just go to the junkyard and pull one from a car there. That's what I did, cost me $13 and works great so far. If it craps out on me I'll just go pick up another one from the yard.

[nando]

What are the bushings like on these motors? Would it be possible to turn some new ones on a lathe and repair it? I see they are like $300+ new.

it's not the bushings that cause the noise (I think you mean brushes). it's the bearings, and unless you have the equipment to balance it at the 10,000+ rpm the fan spins at full speed, you can't replace them yourself.

[e30BMart]

yeah the bearings... i'll proly go to the junkyard someday... 13 bucks is a great deal :P