'95 525 turned on blower and smells bad (burning?)

[5mall5nail5]

Hey guys - been a while. I know of the issues E34s have had with the blower motor catching fire, etc. The other day I was driving and turned on the heat and smelled a burning smell. It didn't smell plasticy or anything... it almost smelled more leafy. But, could be my imagination. Not using the blower until I figure it out.

That said, this is on a '95 525i - was there any update to this year that would make me feel better about the car not burning down? Was going to pick up a Behr blower but its almost $300. I think I might pull the one out of my "race car" first. Is there anything I should check before deeming this issue as the blower and replacing? PS - the blower works fine. No grinding, no squealing that I can hear.

Thanks all!

[Creesic]

Check the resistor in the driver footwell and check the cabin filter in the passenger footwell. The latter is a pain to remove.

[The Chauffeur]

I just replaced my blower a couple of days ago (although my car is a '91), and here are my 2 cents:

Mine had never been replaced before, I think, as the plastic strap on the cover still had the little plastic leash attaching both ends; there was a huge amount of gunk and leaves behind the bulkhead, the blower cover, and around the blower itself... I know they're pricey, but I'd read enough horror stories, and I'd say better safe than sorry; and if not replacing the blower, I'd at least do an extensive cleanup of the whole compartment. Just my opinion...

[bennyg]

I just replaced my blower a couple of days ago (although my car is a '91), and here are my 2 cents:

Mine had never been replaced before, I think, as the plastic strap on the cover still had the little plastic leash attaching both ends; there was a huge amount of gunk and leaves behind the bulkhead, the blower cover, and around the blower itself... I know they're pricey, but I'd read enough horror stories, and I'd say better safe than sorry; and if not replacing the blower, I'd at least do an extensive cleanup of the whole compartment. Just my opinion...

Agree with this.

Also noone with LHD has any right to complain about accessing the filter. Us RHD people have to do it with a steering column and pedals in the way

[The Chauffeur]

Agree with this.

Also noone with LHD has any right to complain about accessing the filter. Us RHD people have to do it with a steering column and pedals in the way

Not just that... I see you have a 540... Us with an m50 have it easy! My hands are still pretty banged up from changing the blower, but I can only imagine what a pain in the rear must be on cars with a V8 (and for that matter, also 535 and M5 owners) or the earlier models with the expansion tank on the bulkhead, so the OP and me should consider ourselves lucky!

[moroza]

Actually, the blower is no big deal to reach on an M60 car. You just loosen the coolant tank and swing it to the side.

Jon, have you actually looked at the blower motor housing yet?

I got a Behr blower for ~$140 (wholesale price via the small indy shop I worked at the time) in '15. VDO brand is made in China. Hella is available and made in Austria IIRC.

[The Chauffeur]

Actually, the blower is no big deal to reach on an M60 car. You just loosen the coolant tank and swing it to the side.

Thanks for bursting my bubble!!!

[Tre0Tre34]

Yep. Obviously check the resistor and clean the accumulated crap out of the heater box.

My blower fan made some pretty horrible noises promoting me to replace, but i wont tell you NOT to replace it.

Also could just be the dust accumulation on the heater core if you haven't used the heat in a while. Mine always smells a bit funny when the heat actually kicks on for the first time in the season.

And yeah. The blower motor is not a lot of fun with an m30 under the hood. One screw for the access panel is so tough to get at, that I didn't reinstall it to make things easier in the future

[CarterH]

My heater usually smells a little odd, I could best describe it as being like a slight coffee kind of smell. From my own research I've read that moisture and condensation etc ends up leading to mold and that just gets stuck down there in the system. The smell isn't unpleasant either, most people that have been in my car seem to like it curiously.

[moroza]

My heater usually smells a little odd, I could best describe it as being like a slight coffee kind of smell. From my own research I've read that moisture and condensation etc ends up leading to mold and that just gets stuck down there in the system. The smell isn't unpleasant either, most people that have been in my car seem to like it curiously.

Inhale enough of the right kind of mold (rye ergot in particular) and many things will be *very* curious to you

[locknload]

Might also just put an ammeter on it to see what the actual amperage draw is before you spend a lot of time and $ you'd rather apply elsewhere.

[CarterH]

Inhale enough of the right kind of mold (rye ergot in particular) and many things will be *very* curious to you

Whether it's mold or not, I don't know. I figure it's probably just old dust, dirt, smell of the warm rubber hose itself etc since the heat in the car has been rarely used in my few years of ownership and nobody really needs a heater in my country. I spray some disinfectant and other stuff down the vents every few months to kill any potential bacteria but obviously I haven't gone as in depth as I should. I've no idea how to do a bigger clean really.

It's also worth noting this smell only happens on heat, never on just fresh air or when the AC is on.

[ross1]

Hey guys - been a while. I know of the issues E34s have had with the blower motor catching fire, etc. The other day I was driving and turned on the heat and smelled a burning smell. It didn't smell plasticy or anything... it almost smelled more leafy. But, could be my imagination. Not using the blower until I figure it out.

That said, this is on a '95 525i - was there any update to this year that would make me feel better about the car not burning down? Was going to pick up a Behr blower but its almost $300. I think I might pull the one out of my "race car" first. Is there anything I should check before deeming this issue as the blower and replacing? PS - the blower works fine. No grinding, no squealing that I can hear.

Thanks all!

That smell is concerning.
You probably know the blower resistor is nothing more than three coils of high resistance wire that turn electricity into heat rather than pass full current. They are enclosed in a cage but when crap gets right up against them said crap get hot, sometimes fire as you've read. I'll bet you have some leafy debris collected on the bottom of the plenum close to the resistor.
With both the blower resistor and the cabin air filter removed you'll have some access from both sides which enables you to manipulate the junk to one side and suck it out with a shop vac.
As for the motor, see Shogun's site for a way to use an MB blower motor which you can buy new for ~$100.

[LuxurySadler]

Im having the same problem except the smell actually kinda smells like burning plastic. I cant really put my finger on the smell but Id say the smell has a sweet and eggish smell to it. At first I would only really smell it when I turned my heat on. Id just turn it off and keep it moving because I read of potential fires that can happen. But now, even with the heater off I'll still get whiffs of it here and there. I dont know if its just the air naturally coming through the vents when I drive and Im getting whiffs of something thats already burnt or if something else is wrong. If this sounds familiar to anyone, please let me know. Any help is appreciated. Thanks.

[Tre0Tre34]

Sweet smell from the heater box typically indicates a coolant leak inside the heater box.

The o-rings are a relatively common thing to start leaking after this long, but it could also be a leak from the heater core itself, or as i have found in the past, the plastic crossover pipe was actually cracked.

Hate to say it, but it might be best to order ALL of it unless you can afford some downtime to investigate before ordering replacement parts.

[LuxurySadler]

Sweet smell from the heater box typically indicates a coolant leak inside the heater box.

The o-rings are a relatively common thing to start leaking after this long, but it could also be a leak from the heater core itself, or as i have found in the past, the plastic crossover pipe was actually cracked.

Hate to say it, but it might be best to order ALL of it unless you can afford some downtime to investigate before ordering replacement parts.

Thanks for the input. Any further knowledge is appreciated.