Need some education, Jump starting/charging a dead battery Options

[Coondog]

I have read some threads about advising against jumping starting a 914 from car to car. Can someone please explain why this is not a good ideal and is it the same with putting my charger on Hi start power boast mode for 15 minutes which I have done several times. If these have the potential to harm the electrical system then would those hand held battery power boasters also have the potential to cause damage???

BTW....Now I just leave a 1.5 amp trickle charger hooked up. Hope that's ok !!

[stugray]

One thing to keep in mind when jumping any car from another car:

When two voltage regulators fight, bad things happen.
Whenever I jump one car with another, I leave the jumping car running, and THE SECOND the "dead" cars starts, I disconnect the jumper cables (takes at least two people)

When the non-running car gets above a few thousand RPMs its own alternator will kick in and try to regulate the voltage.
If the jumping car is still connected when this happens, the two voltage regulators will each be trying to regulate to their own sensed voltage.
If this goes on for long, one (or both) voltage regulators could be stressed.

It is exciting to watch this when you accidentally connect two different "VREGS" together on a circuit board... fireworks usually ensue spectacularly (followed by some smoke generator action)

And it is not advisable to let a car charge it's own dead battery from completely dead. It does stress the alternator "some".
It might be worse on our old fashioned alternators, but I would bet that newer solid state versions have built in over-current protection.