Both my 1994 W124 and my 1990 W124 donor car have exactly the same problem - a slow and sticking windscreen wiper! I have completely dismantled both units and cleaned and lubricated all gearing (back & front) - a slight improvement, but not much.
The motor is still driving the unit, albeit very unsatisfactorily. My thinking is that the motor would either work perfectly or not at all? Is it possible to have a "lazy" motor? Is it possible for an electric motor to continue constantly working on reduced power? In other words, would a new electric motor solve my problem, or would that be a wasted exercise?
Incidentally, to cover all possible angles, I have even replaced the wiper fuse, just in case the old one was corroded and starving the motor of current.
The motor is still driving the unit, albeit very unsatisfactorily. My thinking is that the motor would either work perfectly or not at all? Is it possible to have a "lazy" motor? Is it possible for an electric motor to continue constantly working on reduced power? In other words, would a new electric motor solve my problem, or would that be a wasted exercise?
Incidentally, to cover all possible angles, I have even replaced the wiper fuse, just in case the old one was corroded and starving the motor of current.