Fan clutch? [Archive] - Bimmerfest - BMW Forums

Fan clutch?

09-02-2008, 05:08 PM
Can the fan clutch get weak and cause an elevation in temp... if so do i need to buy and new fan?clutch or could something have gotten loose or is there a sensor that might need to be replaced?

bimmer dot info
09-03-2008, 08:02 AM
Yes and yes.
If you can stop the fan with some rolled up news paper while the engine is idling when hot you probably need a new one. Also if your car is overheating in trafic but not on the highway that is a fairly good indicator.

09-03-2008, 10:33 AM
great i will try that if it stops by putting paper in it i will need to replace the fan w/clutch correct...

and thanks

09-03-2008, 10:36 AM
Nope, Just the Clutch. Should be no reason to replace the fan itself (unless you stick more than just paper in it LOL...). Here is the BMW part #
11 52 1 466 000 should have it.

bimmer dot info
09-03-2008, 12:26 PM
Some people recomend replacing the fan. If you are worried about yours failing (due to age, heat or damage) you should change it. If not leave it.

09-04-2008, 10:28 AM
well i did what you recomended and I was able to completly stop it from turning with almost no force at all,(not what it should be doing RIGHT????) so i think it is KAPUT i also noticed that the fan itself looks very old and fragile so i think your right when you say repl. while its under construction....
How hard is it to replace i have done my fan/clutch on my Ford Van not sure with the bimmer? any ideas what it cost for the fan/clutch...

bimmer dot info
09-04-2008, 11:55 AM
Check the price on autohaus. There are 2 types of fan clutches. Make sure you get the right one. They are not that hard to replace but depending on which one you have you might need to buy a big wrench.

09-04-2008, 10:27 PM
yeah just did 32mm but noticed that that was not the problem i was wondering why it runs hot by a little tiny bit, it was my auxiliary fan that is not working while temp. gets just a little higher it should be coming on to help cool the radiator , so i did what the big book said and just jumped the from the battery to see if it is the fan motor or the sensor, the fan came right on so it must be the sensor since the fuse is not burned out.
I forgot all about that little electric fan, so i hope this will fix the problem..... do you know if this vehicle has the 2 sensor (high temp and low temp.) set up or is it just a 1 sensor ( high speed deal) i could only locate 1. any clue on the cost of a temp sensor that bolts into the radiator????

bimmer dot info
09-05-2008, 08:24 AM
The big fan should be able to keep the engine cool on it's own unless you are in a desert. The aux fan is for the AC and as a backup for the main fan. You should still change the fan clutch. The normal position of the temp gauge is about 1mm right of center when the car is at normal operating temp.
I thinik the fan switch has a high and low. The fan has a resistor for the low setting that can fail.
Check realoem for the part number and autohausaz or other online retaliers for the price.

09-05-2008, 10:57 PM
i went an picked up the part (aux. fan switch) and that did not do anything at all i am getting lost!! i am running out of ideas, now i have to re- bleed the system again and still don't know why it goes up over have by just about 1 mm. it never done that before? you said that that is normal and i dont have any R-12 in my A/C unit so i dont use it .... i just dont know why my engine makes that noise and it only those it when i get it over that half way mark, no more then about 1MM as soon as i get on the HW its gone after 1 min. of speeding=== back to normal. maybe your right and i should change the clutch i was just trying not to spent any extra money on this if i did not have too, I love my car so much and when my Baby does not feel good i cant sleep good. lol
ok so your saying not to worry about the aux fan and to just change the clutch, i will do that and hopefully it makes me sleep better.. also would you happen to know what the estimated cost is for a valve adjustment i know they need it bad and i have never done BMW's before since there hydraulic and all i dont want to mess with it. all i know the engine has to sit over night ....
and if you read all this thanks for carrying about a fellow.

bimmer dot info
09-08-2008, 08:42 AM
What noise it it making? Which engine do you have?

09-08-2008, 02:08 PM
hard to explain its like bad gas noise pinging like a clung clung in the engine when i am pushing down on the gas going up a hill or just trying to accelerate really fast, but like i said it only does it when its hot or when i drove it for over 20 30 min. it has not done it the last couple of days but i don't drive it much over the weekend so not sure i did put in gas from another station hopping it was bad gas. did a tune up and cleaned the air filter i don't know what else it could be unless my engine is starting to loose compression?

09-09-2008, 07:13 AM
...this may no be your problem but it sounds close... I had something similar cruising speed all is well but when I accelerate the engine starts thumping a low boom boom boom...but stops when I stop accelerating and level off to cruising speed it stopped...turns out that one of the fuel injector was clogged completely and the car was running on 5 cylinders only...the other injector were getting worn injector and no problem after. this was at about 160K miles on the 325

same problem on the 525..a bit heating about 1 mm past center...I've tested the fan and already ordered my clutch fan...caution, I believe they are left hand threaded so remove opposite of what you think.

09-09-2008, 07:20 AM
oops...fat finger wrong post...

09-09-2008, 09:20 AM
Thanks guys i think all is well now i belive... I sat down and did some deep thinking about what could have happend, and came up with me going to one of those never heard of gas stations and putting in some cheap gas "sorry baby" ( i never do that) and its funny when i posted my first add about the "Bad gas engine noise"? thats exactly what it was, so after reading some of this other posts i jumped the gun and thought it must have been overheating and so i went.... putting in a new clutch for the fan a new aux. fan switch a thermostat a complete tune up and had to bleed the system 25 times to have it back to where it was before i started, but i did get that gas out put in some octane boost and filled it up with chevrons premium gas and my baby is running like she had less then a thousand miles on her.... so long story short it was all worth it.
and thanks again for all the advise. I WILL BE BACKKK