560sl overheating

[robaincltnc]

I have noticed that at idle with the AC on my car tends to run hot..the temp pushs max but as soon as I start to drive it comes back down. It seems to be worse on hot days. I noticed the secondary fan(the one in front of the radiato-the small plastic one) doesn't run..or at least I have never ever noticed it running in the past two years that I've owned this car...Would this be the reason that the car tends to overheat at idle? Is there a fuse or something that could have broken causing the fan not to work?
Thanks for you help.
rob in charlotte

Not sure about your car. But with the AC on and the car running you should see the aux fan kick on, it's almost impossible to hear from inside the car. Need to get out and look. Make sure the fan is not running, if so sounds like you found problem. Now you need to find root cause. Fan it's self (don't crap out too often). Fuse, sensor, etc. I am not the greatest at electrical diagnosis. Do a search on the subject, no doubt these guys have already addressed this issue.

Joel

[robaincltnc]

Thanks..I appreciate the heads up..I guess I'm hoping that its just a fuse..does anyone know if a there is a fuse to this fan.

I am going out right now..I will turn on car and ac and see. I really doubt that it will come on.

Thanks again,
rob

[robaincltnc]

Thanks..I appreciate the heads up..I guess I'm hoping that its just a fuse..does anyone know if a there is a fuse to this fan.

I am going out right now..I will turn on car and ac and see. I really doubt that it will come on.

Thanks again,
rob

[RSH]

Yes there is a fuse for the auxiliary fan, It is fuse #1 16amp, in the 560sel manual.

[robaincltnc]

Its #14 in the 560 sl..I checked it and it is good. So there must be another reason for the fan not to engage. I guess I just need to take it somewhere to see. I imagine that there is a switch somewhere that may have gone bad.

Thanks for you message!

[Kebowers]

Often the brushes in the aux fan get grease or crud on them and that results in poor contact and no run. Sometimes you can tap vigorously on the fan hub when it shoulld be running and that will 'reseat' the brushes. Often though you have to either replace (lot of bucks) or disassemble the fan, clean things up, regrease the bearings and go for another 15 years.