Heater fan blowing intermittently on C200 1999 ??

[fast cars]

Mercedes C200 Classic 1999 , can anyone help , the interior heater fan blows intermittently ,switching on and off whilst its set on any fan speed , in this weather its nearly impossible to drive with the glass fogging up , can anyone tell me what I should be looking at to try and sort this? The control for the fan is the simple rotary dial , no fancy climate control here


Thanks

Danny

Edited by fast cars on Sunday 3rd October 13:55

Edited by fast cars on Sunday 3rd October 13:56

[fast cars]

I have found sometimes hitting a hard bump on the road gets it going again ? what could I do to poss sort this ?

Thanks

[fast cars]

Cheers chaps , it is most defo the motor bearings , tried some WD40 on it and its really helped even though its not cured it , new motor or rebuild next !