Fan Clutch Rehab
Article by: John Krawzcyk
Article applies to all BMW models with a viscous cooling fan clutch.
These next few pages attempt to graphically demonstrate the Plumley Procedure for rehabbing Porsche 928 mechanical fan clutches. The one shown below is from my 1979 and it typical of the earlier model fan clutches. Keep in mind this fan clutch is slightly different from the one described in the Plumley Procedure. However the basic
principles of the repair procedure still apply.
This article was originally written for a Porsche 928 (we won’t hold that against them too much ;)), but the fan clutch and repair process is exactly the same for BMW.
The fan/clutch assembly from my 1979 928.
The first thing I did is remove the air intake tubes from the upper fan shroud and then unbolt the (2) 10mm bolts holding the upper fan shroud to the radiator shell and lower fan shroud.
I lift straight up and out: