check you electrical wires from starter to alternator,for warm wires.My w126 has a place on passenger side fender down by alternator where the wires junction.I would asap carry a fire ex. and think about a battery cutoff switch.Older cars are bad for going up in flames.Also check if you had heater on when you start the car.The heater and air cond. control are bad to catch fire,if the aux. water pump has become stuck.They reccomind attaching a 1 amp fuse to aux. pump. to save car.

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1999 w140, quit voting to old, and to old to fight, a god damned veteran, deutschland deutschland uber alles uber alles in der welt