My 1989 300SE with M104 engine just developed a periodical noise that sounds like plastic hitting plastic.
It appears that the pulley that the fan is attached to is not balanced. So I presume that the bearing has gone bad. Fan blade ends seems to hit somewhere.

I need to inspect better and figure this out.

great just found the link w help !!
W126 300se Viscous Fan Bearing Bracket Replacement

Thanks to Ivanerrol !

UPDATE 9-9-13

With the help of a very conscientious member, Arthur Dalton, I was able to do some bullet point inspections. I determined that my motor mounts were OK and now I did observe the fan pulley throw itself outward toward the radiator simultaneous to the fan clipping noise (fan extremity slap).
So now I have to price out the fan bearing bracket assembly and figure out how the fan clutch is removed.

I am fairly certain that the radiator does not really have to be removed.

But I wonder whether the belt tensioner is going to be any good after it is loosened. I think I have read that this piece is also a carpicious itme that goes south when you don't want it to.



So, yes, these pulley bearings wear out apparently.

Thanks again Mr. Dalton !

__________________
1979 300D 220 K miles
1995 C280 109 K miles
1992 Cadillac Eldorado Touring Coupe 57K miles SOLD
********************
1979 240D 140Kmiles (bought for parents) *SOLD.
SAN FRANCISCO/(*San Diego)
1989 300SE 148 K miles *SOLD

On the E320 from 2000 onward they deleted the whole fan clutch and assembly, there's just one beefy electric fan attached to the shroud on the radiator...

__________________
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