alternator fan is loose - PeachParts Mercedes-Benz Forum

airfoill · #1 11-06-2002, 11:08 PM

Hello All,

Has anyone else experienced this problem. I have an 82 240D. The car started making chirping noises when the car was idling so I started investigating what I thought it might be. Sure enough it was the alternator because I have had this problem before.

I am currently on my third rebuilt alternator. I replaced the first alternator two years ago because it was not charging, the second was replaced late last year due to the alternator fan becoming loose, so I returned it and was given another rebuilt alternator. Now the current alternator fan is starting to become lose on the pulley. I've tried tightening the bolt that holds the alternator fan in place but that does no good; the fan still moves within the pulley. Why are these alternator fans getting loose? I made sure they were tight before I installed the alternator. Any ideas?

Thanks

Herb
'82 240D
'87 300SDL

#2 11-06-2002, 11:35 PM

I just replaced my alternator and the fan keys in on the alternator shaft. My rebuilt alternator required the key, fan and pulley off the old alternator.

How has the fan come loose? Has the nut and lockwasher come loose as well? Or is the fan rotating on the shaft?

airfoill · #3 11-07-2002, 08:07 AM

The key fan is intact however, the fan itself seems to wear on the key and eventually spins on the shaft.

Herb
'82 240D
'87 300SDL

#4 11-14-2002, 04:52 AM

had the same problem with my 87 300D. had my third replacement. the first is due to a missing lockwasher. the second is due to a worn out pulley (the inner part of the pulley detached from the rest of the pulley leaving the inner part still attached to the shaft and the other part freely rolling with the fanbelt) about the third replacement... i was running quite fast (about 160 kph, quite fast in the philippines) and suddenly the screw of the pulley loosened. i dont know why?!! at the repair shop, we opt to use an electric screw driver to fix the screw in place. but still, there's this peculiar noise from the alternator. I dont know if we have the correct sequence for the pulley, fan, washers, etc. can anyone provide the correct sequence? and also, we are not quite sure if the lock (the tiny metal) is the culprit.