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The onset of the recent cold weather within the UK has bought about the impending failure of my fan blower assembly which is now making some very unique screeching noises dependant on fan speed.
I think its the the Fan bearing based on the noise pitch changing when cornering but cant confirm until its removed (To cold at the moment..)

Out of curiosity, have many others had this type of failure & does anyone know where I can get a reasonably priced replacement without paying Stealership prices.

Any help would appreciated as I am about to do an Insp 2 plus all the suspension springs & rear beam mounts, so I am attempting to keep the costs down for this month anyway...!

Regards
Farrell
 

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farrell said:
All
The onset of the recent cold weather within the UK has bought about the impending failure of my fan blower assembly which is now making some very unique screeching noises dependant on fan speed.
I think its the the Fan bearing based on the noise pitch changing when cornering but cant confirm until its removed (To cold at the moment..)

Out of curiosity, have many others had this type of failure & does anyone know where I can get a reasonably priced replacement without paying Stealership prices.

Any help would appreciated as I am about to do an Insp 2 plus all the suspension springs & rear beam mounts, so I am attempting to keep the costs down for this month anyway...!

Regards
Farrell
Hi!!
This is what I suspect a quite common "problem" on 5-series (and other 10-15year old cars) My fan is also noisy(been the last 3 years) but it doesn`t seem to be failing any time soon, only thing is that the noise is wery annoying.
Well, you can try scrappers, but obviously the used fan is likely to have or will soon have the same problem.
You could try OEM part at independant partsdealer (the fan is made either by BEHR or some other that I can`t remember now) B thebestway to check the make is to look for yourself-take away panels in the driver footwell and check the side of the heater for stickers.It is not sure only by checking at your local stealer based on the VIN, as the make of the heater varies apparently at random(as I was told)
At your stealer the fan/motor will set you back maybe 130£.

:cheers:
Sakke
 

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Discussion Starter #3
DrSakke said:
Hi!!
This is what I suspect a quite common "problem" on 5-series (and other 10-15year old cars) My fan is also noisy(been the last 3 years) but it doesn`t seem to be failing any time soon, only thing is that the noise is wery annoying.
Well, you can try scrappers, but obviously the used fan is likely to have or will soon have the same problem.
You could try OEM part at independant partsdealer (the fan is made either by BEHR or some other that I can`t remember now) B thebestway to check the make is to look for yourself-take away panels in the driver footwell and check the side of the heater for stickers.It is not sure only by checking at your local stealer based on the VIN, as the make of the heater varies apparently at random(as I was told)
At your stealer the fan/motor will set you back maybe 130£.

:cheers:
Sakke
Thanks for the feed back Sakke
I found out quite a lot yesterday about these parts.They are made by BEHR in Deutchland. There appears to be two versions. One for Aircon & one without. The parts are also fitted in many other Beemers with commonality on the E32 & E38 series to name a couple.

You were spot on with the cost as well & the fact that they run noisy for a long time means that I will probably strip the part & clean up the fan shaft & bearing & treat them with Tetraglide PTFE lubricant.

If the bearing is significantly worn then Im going to machine up some new
PTFE or Bronze bearings.

Will let you know if I cure it.

Regards
Farrell
 

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Gents,

Replacing, overhauling the heater blower is a time consuming job, mostly because you have to find out how the heater blower has to be removed.

You also have to remove the intake plenum (which is 30mins if you know how to) to get access to the center bottom screw of the heater panel. The other five screws are more easy to reach, yet a bit tricky for the other two lower positioned screws.

To remove the heaterfan, you only have to remove the cover of the fan housing and release the locking clip. But to get it out requires some puzzling, especially since the wiring loom sits in the way and does not give much room. I solved that problem by cutting some of the tiewraps at both sides. This gave me the clearance that I needed to push toe wiring loom downwards. The created gap then is enough to remove the heater fan. But the plastic fans (that can't be removed) still have very little clearance.

The problem on my car was not the fan, but the wiper mechanism! To replace that part, I had to remove the heater fan and it's entire housing. The fan itself was OK, but the brushes where 50% worn. Given the fact that this is a time consuming job on an E34 S38, I just bought a new one as part of a preventive repair. Yes, it is not cheap, but you don't want to do the same repair for a second time.

6months later, the heater fan (and sword) failed on my fathers E32 735i. On an E32 M30 the replacement of the heater fan is much easier so I reused my old E34 fan in the E32!

BTW, the bearings can't be replaced as both plastic fans are molded on the shaft and then balanced during production. You can try to clean and lubricate them (using light machine oil) and replace the brushes (which are not available as seperate parts (from BMW), but given the fact that it requires so much work on an E34 S38 (or E34 M60) I recommend an investement in a new part (~170 euro ex VAT and ex discount).
 

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Discussion Starter #5 (Edited)
Thanks or that Raymond.
I had a feeling the bearings might not be a removable item but have not started to strip it out out yet (Tomorrow) so your post has answered part of my investigation.
I also agree that doing a Job once is usually the best course but in my case having spent £1000 in parts & paint work since Jan & another £400 this month on Suspension & service items recently, I have come under increasing pressure from my better half to keep some money to feed the family this month......!

The noise is so bad that attention, even if short term or a pain is reqd.
The price of the part in UK is 230 Euros once the VAT @17.5 % Is added

The proposal of using Tetraglide PTFE compound is however sound.
Machine oil tends to be thrown from the shaft by by centrifugal force soon running the shaft & bearing dry.
Tetraglide products have been spec'ed by other Engineers within our test facility for low mass high rpm shaft speeds.
It does not throw from the treated surfaces providing they are degreased
prior to application.

Thanks
Farrell
 

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farrell said:
The proposal of using Tetraglide PTFE compound is however sound.
Machine oil tends to be thrown from the shaft by by centrifugal force soon running the shaft & bearing dry.
Tetraglide products have been spec'ed by other Engineers within our test facility for low mass high rpm shaft speeds.
It does not throw from the treated surfaces providing they are degreased
prior to application.

Thanks
Farrell
You have a valid point against using light machine oil!

The main problem with the heater fan is that it is an open design, which means that dirt and wear-out from the brushes get's everywhere. Especially the bearings are susceptible to that. This was the cause on my fathers E32 also. One of the bearings started to fail, which resulted in a higher current drawn from the power driver (sword). In the end, the bearing had so much resistance that the power transistors of the sword overheated and collapsed under a thermal meltdown. This was also the end of the sword.
 

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Discussion Starter #7
raymond woertman said:
You have a valid point against using light machine oil!

The main problem with the heater fan is that it is an open design, which means that dirt and wear-out from the brushes get's everywhere. Especially the bearings are susceptible to that. This was the cause on my fathers E32 also. One of the bearings started to fail, which resulted in a higher current drawn from the power driver (sword). In the end, the bearing had so much resistance that the power transistors of the sword overheated and collapsed under a thermal meltdown. This was also the end of the sword.
Thanks Raymond
Good factual information.
Its always cause & effects is'nt it...!

Cheers
Farrell
 

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farrell said:
All
The onset of the recent cold weather within the UK has bought about the impending failure of my fan blower assembly which is now making some very unique screeching noises dependant on fan speed.
I think its the the Fan bearing based on the noise pitch changing when cornering but cant confirm until its removed (To cold at the moment..)
My fan blower (for the fully electric automatic climate control) has showed the exact symptoms described above for some time now. It tends to run a bit more silent when getting very cool air from the AC, and as described by Farrell the noise changes when cornering. I understand it's quite a job to replace it, and I'm not comfortable with removing the plenum etc so I would leave it to my mechanic. At the same time my wiper linkage would need fixing too.

Having recently tidied up my non-SLS rear setup with all-new 535 M springs and dampers, I would rather not undertake this job right now... (Aah, the expensive joy of M5 ownership!)
I therefore wonder whether the fan can be somewhat easily accessed so that I can lubricate it with Tetraglide PTFE, as suggested by Farrell? I understand it is a short-term fix, but it will at least help my wallet. :)
Farrell, did you fix your fan blower or are still keeping the noisey one?

Regards,
Patrick
 

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Discussion Starter #9
Hi
I removed the the Fan blower assembly & replaced with a new part.
I did this in conjunction with fitting new engine mounts so lowered the engine down to give easier clearance to the Firewall access panel.

The bearings are a nasty plastic which had ovalised.
You could keep it quiet for a short period but even using a PTFE dry lubricant, Im not sure how long this would last.

Raymond was right.
Do the job once as you are not going to want to do the job twice.
Its a right pain.

Farrell
 

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I Have this job and the wipers to look forward to whilst the engine is out! Spent the budget on trying to get the engine back together for a minute though!
Just out of interest,should I replace everything wiper wise or just linkages and anything that looks worn out?

Farrel,Did you find a cheaper option heater motor in the end or just go to the stealers?
 

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Geach said:
Just out of interest,should I replace everything wiper wise or just linkages and anything that looks worn out?
Replace the entire wiper mechanism. Don't use a salvage (used) part since the ball bearings from the used part may perish sooner or later. One cannot really tell when these break down. One moment, the arms are firmly attached to the ball bearings and another moment they are not. The cause are the seals that isolate the ball bearing's and it's grease from the environment. Their location is such that they have to endure both extreme humidity and temperature variatons and once they age, their protective function is reduced, causing the grease to be contaminated by moisture/dirt and there you go.

Replacing the wiper mechanism is even more a PITA then replacing the heater fan that has to be removed also to get access to the wiper mechanism. Like the heater-fan, I used a factory new part for exactly this reason. As said, you don't want to do the work twice.
 

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My Fan is making a lot of noise and going up and down with revs--I can hear the sound coming from the center vents, and it is annoying when the radio is off...it is quite audible. Anyone else have this problem?
 

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This used to blow, now it just plain sucks...

OK, my blower limped - with varying amounts of noise for a time, then big smoke...

For those of you who have done the blower/sword replacement, can you give a description of what has to be done?

Raymond gave the best description to date as part of this link, but I am unsure whether the blower assembly comes out through the dash or the engine compartment. From the look of the part from the TIS, it must come through the dash.

Thanks in advance for the help.

Mike
 

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Sword = Footwell
Fan = Engine compartement!

-Diconnect battery
-Pull off plenum
-Remove heatervalve, aux water pump, +terminal, and all other ****e on bulkhead
-Remove bolted piece of bulkhead
-Remove thin plastic cover
-Remove thick plastic cover, yes, there are 2 little bast*rd clips on the backside you'll need to fiddle with.....

Voila: you have reached the fan-motor.....


Michael William said:
OK, my blower limped - with varying amounts of noise for a time, then big smoke...

For those of you who have done the blower/sword replacement, can you give a description of what has to be done?

Raymond gave the best description to date as part of this link, but I am unsure whether the blower assembly comes out through the dash or the engine compartment. From the look of the part from the TIS, it must come through the dash.

Thanks in advance for the help.

Mike
 

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Time Hack, motor and shroud out...

It's out, my motor had steel bearings, looks ok, that is unless you are talking about all the chipmunk acorns, and dead babies...

Not pretty, so how does the filter come out?

Mike
 

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On LHD:

-remove glovebox (2 hinges and 2 straps)
-remove bit of black plastic trim with the torck-socket (1 screw and 1 clip)
-remove carpet on the tunnel (1 screw)
-remove ventduct behind glovebox (3 screws)
-undo three wiring connectors and pull wiring out of the way
(connectors are blue, yellow and black, the black one is in the sword)
-remove sword (2x T25/T30 Torx screws.....)
-remove the screw in the bottom of the white piece of plactic the sword is mounted in and turn the black clip above the swordhole counterclockwise.

Swear and curse to pull the white bit out, I usually pull the 7 or 8 torx-screws out of the evaporator-cover (no.8 in this link) out and remove it to be able to see what I'm doing and vacuum the dirt out.

Put your hand in the hlot you've just made and you should feel the tab which lets you pull the filter out......

In case you're wondering, I did mine last weekend for the third time!!!!!

Or:

http://www.bmwe34m5.com/node/219

Michael William said:
It's out, my motor had steel bearings, looks ok, that is unless you are talking about all the chipmunk acorns, and dead babies...

Not pretty, so how does the filter come out?

Mike
 

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Thanks Stevie, upon further inspection I find that the blower resistor is pretty fried, uncoded control unit looks ok, haven't yet found the sword. Going to Bavauto.com for the blower motor ($219.95) and the resistor ($18.95) as it is only a 1 hr drive from my house. At this point I am betting that the sword is ok as I had all fan speeds at the time of the failure and the shape of the resistor would certainly explain the smoke.

BTW, I was able to get the blower out without taking any of the intake assembly apart.

Sorry about your luck with this system, I hope I am not in the process of following your footsteps on this...

Mike
 
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