Thermostat replace How to remove fan?

[Scott Crosby]

OK 2000 528i. I am attempting to replace the thermostat. Drove the car yesterday and the temp went all the way up. I purchased the new thermostat. but can't figure out how to get the fan off. The fan housing cannot be removed with out the fan blade comming off. When I turn the nut on the back side between the fan and pully, the fan the belt turns. I read that the nut was a left thread but how can I keep the pully from spinning? I am having a feeling that this cost savings idea is not going to work in the end. I mean, my god how hard can a thermostat be to replace?

[MantecaBMW]

I just replaced the alternator on my 530 and had the same problem. I ended up using a strap wrench to hold the pulley, put a long crescent wrencn on the 32mm nut and gave it a firm hit with a rubber mallot. That broke it loose and took about 6 more turns to finally come off. Installation is reverse. And yes, it ia left handed thread, so loosen clockwise facing the motor. Also be careful as the pulley is plastic.

http://www.bimmer.info/forum/showthread.php?t=8868&highlight=cooling+fan

[Scott Crosby]

Thanks for the reply. Does that mean I have to remove the belt? I was trying not to have to do that.

[632 Regal]

http://www.bimmer.info/~632regal/Fan%20removal%20tool.jpg

[MantecaBMW]

except the 2 dealers I went to said they couldn't authorize selling it to a retail customer.........frickin idiots!

[632 Regal]

make one with a grinder and a drill, the metal cost like a dollar.

[John in CT]

Sears gets 28 bucks for the 32 mm open end wrench, you will need it for any front-of-motor work, belts, waterpump, belt rollers, etc. My big adjustable wrench was too thick to get on the fan nut. if you are in CT near New Haven you can borrow mine. I wacked it w/ rubber mallet, no problems except the six turns take some minutes. I didn't have to disturb belts when I did my T-stat a few weeks back. I did upgrade the T-stat housing to aluminum, maybe yours already has it. On M50 motor bleeding is done on top of Radiator, driver's side theres a plastic screw you open, a little hard to find but easy once you do. I also drilled a 1/16 hole on top of T-stat, it was a little tricky but in theory aids bleeding air from system.

Best,

John
1995 525im

[Trevor]

The rubber mallet trick worked fine for me.
A recommendation is to put some cardboard across the fins of your radiator, just in case you swing and miss.......

Fan clutch is free spinning, but a gentle knock on the spanner/wrench/socket arm with a rubber mallett should be enough to free it up.

It's a given that you'll need 2 litres of BMW genuine coolant when you refill. Not cheap but certainly worth it.

Also, there are at least two temperture rated thermostats. When I first replaced my thermostat BMW gave me a 90 degree (celcius) thermostat which made the car run hot. Took it back and got an 80 degree one.

[liquidtiger720]

trevor- how hot was it running? I just replaced the t-stat and the gauge is exactly 1 bar over the center line.

~

[Scott Crosby]

Thanks for the input. As soon as I saw that tool I knew I could make one. I had a piece of 1/8" stainless, just drilled a hole and piece of cake. Nut broke free. 5 min later thermostat was out. Thank you!!!!!!

The temp gauge maxed out on my wife's way to work. It's only 2.5 miles from home. When she pulled into the lot she noticed it. We had the same problem last year with our z3. It was still under warrenty so the dealership fixed it. I am just guessing it's the thermostat, but I'll find out when I get the new one in. I ordered it and it should be delivered monday. Just waiting now.

[Trevor]

Mine was running about 1/2 bar over the centre with the 90 degree thermostate and dead on the centre bar with the 80 degree