That is why I asked, I didn't have any good data on it.donald wrote:Depends on the car of course, but sure what do you say it is?TimLee wrote:But where are getting the idea that starting an ICE with a weak battery could ever attempt to pull 1000 amps?
I found the following in an online guide to resolving ICE starting problems.
I think those values are more typical.http://www.aa1car.com/library/us1296.htm" onclick="window.open(this.href);return false;
A good starter will normally draw 60 to 150 amps with no load on it, and up to 200 amps or more while cranking the engine. The no load amp draw depends on the rating of the starter while the cranking amp draw depends on the displacement and compression of the engine. Always refer to the OEM specs for the exact amp values. Some "high torque" GM starters, for example, may have a no load draw of up to 250 amps. Toyota starters on four-cylinder engines typically draw 130 to 150 amps, and up to 175 amps on six-cylinder engines.
An unusually high current draw and low free turning speed or cranking speed typically indicates a shorted armature, grounded armature or field coils, or excessive friction within the starter itself (dirty, worn or binding bearings or bushings, a bent armature shaft or contact between the armature and field coils). The magnets in permanent magnet starters can sometimes break or separate from the housing and drag against the armature.
A starter that does not turn at all and draws a high current may have a ground in the terminal or field coils, or a frozen armature. On the other hand, the start may be fine but can't crank the engine because the engine is seized or hydrolocked. So before you condemn the starter, try turning the engine over by hand. Won't budge? Then the engine is probably locked up.
I think the highest currents would be the starter locked rotor current value, but I did not find a good source for those.
But probably under 300 amps.
I guess there is some possibility that the bad battery on the ICE might have developed a complete short. But that is pretty unlikely, they sometimes short individual cells, but not usually the overall battery.
Jump starting an ICE is an activity that does present risks. Are way too many injuries every year when people do it wrong.
But carefully following Ingineer's carefully outlined instructions using a LEAF in Ready mode there is a lot less risk than many other approaches.