'94 E320 start problem mystery

[sulkande]

3 days back when it was raining and quite cold (< 60 F) the engine did not crank up at all, though all other electrical devices like radio a/c were working. On the day before that, it did not start at the first attempt but after waiting for couple of minutes. I took it into the garage and it never showed any start problems for the whole day (it was not that cold today maybe 65 F). The mechanic told that he knocked on the starter(huh??) but could not find any problem, and told me to bring back when it happens again.

Any clue to this mystery??

 

[Spike]

Sounds to me from the mechanics description that the solenoid is duff or the starter motor is worn....or at least the brushes are struggling to make a good connection to the contacts on the motor itself.

The temperature could potentially cause the starter motor to contract (very slightly) thus exaggerating the problem somewhat. A temporary fix to get you moving is to either give the starter a belt with a hammer or to put the car in gear and rock the car so that the starter motor turns a little - hopefully onto a better contact patch.