DIY: Aux/mechanical fan to electric fan swap

well, I did the swap and I left the clips on. All works well so far.

I like it, I like it and I like it The car is so quiet at Idle, less vibrations too. I noticed my RPM at highway cruising speed (with cruise control, 75mph) went up a notch from 2300 RPM to 2400 RPM, the cars warms up quite fast now, before I even reach the Highway (2,5 miles) and psychologically the engine feels kind of lighter/smoother All I can add to this all is Solidjake FTW!! I'm gonna spam this swap all over the Dutch Bimmer boards

The clips are there to balance the fan. So I'm glad you left them on.

Te electric fan is far superior to the mechanical fan because of the damaging vibrations to the pulleys belts and cooling system

Originally Posted by Vigilante

I like it, I like it and I like it The car is so quiet at Idle, less vibrations too. I noticed my RPM at highway cruising speed (with cruise control, 75mph) went up a notch from 2300 RPM to 2400 RPM, the cars warms up quite fast now, before I even reach the Highway (2,5 miles) and psychologically the engine feels kind of lighter/smoother All I can add to this all is Solidjake FTW!! I'm gonna spam this swap all over the Dutch Bimmer boards

Awesome

enjoy!!

Originally Posted by fire730

The clips are there to balance the fan. So I'm glad you left them on.

Ah great, thanks. Now my mind is fully at peace with it

Tip: If you go to BMAParts.com and type in the part number, the product will say it is not currently available, however, if you PM Yves Bright on the website, he can get an OE Fan for $182!!!

i have question. What if my new electric fan fails during hot day in city ? You cant notice that becuase its relatively quiet. And i dont want to see temp needle in red light.

So there is no warning before you end up in smoke and exploded cooling system.
Mechanical fan is making some drag onto belts and other things but its more reliable beucase it fails rarely and if it fails, you can hear it that fan is not making truck noise. And most of the time when mech fan fail, its always engaged
= its cooling your radiator even when its broken.

i have question. What if my new electric fan fails during hot day in city ?

You'll see the temperature gauge moving into the red.

So there is no warning before you end up in smoke and exploded cooling system.

If it goes that far, you're not paying attention.

Mechanical fan is making some drag onto belts and other things but its more reliable beucase it fails rarely and if it fails, you can hear it that fan is not making truck noise. And most of the time when mech fan fail, its always engaged
= its cooling your radiator even when its broken.

The mechanical fan can fail by locking and spinning all the time, which makes more noise but doesn't hurt anything. The mechanical fan can also fail by losing it's blades and sending them into the radiator, and has also been known to dent the hood. If you scan these discussions, you'll find a number of failures like that.

If you want to drive and don't pay attention to the gauges, you're correct, you should stick with the manual and electric fan combination.

yes thats true but who wants to drive with eyes sticked on temp needle ?
And you know that with some passengers in car, music etc you are not able to watch temp needle always.

Other thing is that temp needle will go into red in few seconds and that few seconds can kill your engine because few seconds in red light = thousand of dollares.

I know what im saying. I had one engine swapped. And why ? I was trying to park my car between 2 cars when my viscous clutch failed. I had my head turned on rear glass when trying to park correctly and when i turned my head to front, i saw white steam.

Electric fan can fail anytime because its fact. And imagine that you are driving in city with 38C outside, talkin with friend and you didnt notice needle in red.

All you wrote about mechanical fan is true but fact that its more reliable in term of cooling is proven by bmw mechanics. I want to do swap to electrical too but im just thikning and asking myself what if ...

I know that mechanical fan can damage some other things but mechanical fan will fail when clutch is engaged and you spin your engine to 6500rpm. And when cluthc fail, you can hear it. When you hear it = its time to replace clutch.

And one thing should be useful : sound warning when temp needle goes away from 12o`clock position, constant beeping when temp needle touches line after 12oclock position etc. Something like beeping or long beep which depends on temperature.
I think that with this feature, most of engines which were blown should be still alive.

I`ll speak with my friend about it. If its possible to install sensor into engine bay and make warning system based on cooling temp.

.m

Might be possible to do that. I hope someone does come up with something like that.

Someone has developed a system that monitors the coolant temperatures and alerts the driver of overheating. It's pretty neat stuff to read about. The big surprise is the large window of temperatures in which the needle keeps its 12 o'clock position as programmed..

Anyways, here's a link to the Coolant Snitch
http://zhpregistry.net/Tech/CoolantSnitch.aspx

Looking forward to someone who can reply to MichalTT's statements. Maybe even E46Mango because we have been tag teaming the boards today! But yes, I was almost about to order this until reading Sansho's reply...made me think that these electric fans CAN fail, and what about the people who said the fan was running up to 10 minutes after the car was shut off?

...and what about the people who said the fan was running up to 10 minutes after the car was shut off?

It is normal logic for the computer to run the fan for up to 10 minutes after the engine is shut off, based on the computer calculated catalytic temperature.

Don't forget that even if you have the mechanical fan you still have the electric aux fan that can fail. You will overheat just as bad and cause just as much damage if you don't notice the temp gauge going up. Judging by the awful sound it makes when its on I bet its lower quality/lower lifetime than the "full" electric fan too.

I'd be curious to compare the actual failure rates between the two parts.

Thanks for this diy solid. I think I'm going to tackle this one. What would you rate the difficulty level at? I believe I have all these tools, not sure what fan clutch tools are though.