My mechanic tells me the reason why I have a problem starting the car,after the car had been driven for an hour or so is because the output of the alternator is low while the engine is warm/hot. In fact the car would start after 1/2 hour or so of waiting. Last weekend I was not able to start the car at all while sitting on my driveway under the brazing sun,but the same thing happened at night... Anyway the mechanic says the output from alternator was below 13 volts.
He put a new one on and he is getting 13.5 volts now,but he says that he is not happy yet,that needs around 13.8 volts...
My questions are: Is his diagnose correct as far as the non starting problem?
Is he right as far as the alternator output? What kind of Amperage should the alternator have? 80 or 120 Amps? I dont know what he is using... 1990 740 GLE
16 Valve...Along the way some electric instruments stopped working : radio,washer pump,horn,speedometer...
Tks for yr suggestions