While you wait for answers, we may have found some information which could help you.
Click here for Belt Change PartsRepairing a Bosch AL 3640 CV lawnmower charger?
Bosh roteck battery mower shudders/spins but then stops?
How can I fix my Bosch Rotak 37 lawnmower?
How can I fix?
Bosch charger Al 3640 cv for lawn mower is not charging. No lights?
Bosch Rotak cuts out after 3 seconds?