Running Car Without Battery DONT DO THIS!!!

[MrAl]

Hi again,

Very interesting replies.

I have also read now that testing an older car by removing the battery to see if the alternator can run the car is not a definitive test either. That is because an alternator that is just 'weak' may be able to run the car but not charge the battery properly.
Knowing a lot about electronics and generators and stuff, i can say that this is very valid. While the test might show a very dead alternator, it may not show a semi defective alternator. Alternators also have a field winding, so if one phase was blown it might still be able to energize that winding, but i can be sure about this.

I think most of us have more modern cars anyway now so i would never suggest doing this anymore anyway.

[rspi]

Most people suffer a dead battery when the alternator dies. When you jump it, if the alternator is bad, it will die as soon as you disconnect the cables.

[MrAl]

Most people suffer a dead battery when the alternator dies. When you jump it, if the alternator is bad, it will die as soon as you disconnect the cables.

Hi there Robert,

Oh that's an interesting view point too. If the alternator does not work, nothing gets damaged
Thanks for the additional thoughts here.

Now that i think about it, this actually happened to me with my old Hyundai. I was at MacDonalds drive up and the car died. I got a jump from a local shop. 10 minutes later, the car died again at a stop light. Cost me 350 dollars to fix because of the bad alternator. Might still have the receipt somewhere.