Car Battery

[Pat]

I had the alternator on my Corvair powered buggy rewired as a single wire. It will start and run with no battery present.

Edit: Of course it has to be jumped to start it.

[Racer X]

there you go. It is possible, and actually fairly common on older vehicles that have upgraded charging systems.

[Grateful11]

[quote Filliam H. Muffman]I have not had a battery last less than 4 years since 1986.
Almost every battery I looked at recently at Autozone was made in Mexico that might explain why they're crap now.

[elmo3]

[quote Racer X]elmo3, you obviously have very limited automotive theory background.
hmmmmm. That may be the case, but I do have some automotive practical experience that says a modern car just STOPS DEAD when the battery is disconnected.

One of them is a 94 Lexus.

[kap]

UPDATE: Got the battery checked out. It is still good. However, there is a problem which my S/O neglected to mention and it might have something to do with the car not started up yesterday morning: when I shifted the selector lever to PARK, the car rolled backwards! There were also dull clicking noises coming from the gearbox. I called up our mechanic he suspected the overriding switch. So we'll be taking it to the guy this coming Sat.

Kap

[Racer X]

possibly because it will fry the diodes, and then it doesn't make any power, or it isn't one of the designs that self-regulate itself. Many can't. Many need a battery to act as a "shock absorber" and as something to push against.

And many need the battery as a refference voltage, so the voltage regulator can adjust the field output to generate the proper voltage and current. Without the battery to act as a moderating load with internal resistance, the regulator will chase field current up and down trying to keep a constant output. Pretty much like 2 dogs running in a circle trying to get the other's tail.

The self regulating ones are frequently the one wire versions, but not always.

Had you said "That may be the case, but I do have some automotive practical experience that says many modern cars just STOP DEAD when the battery is disconnected. " you would be correct.

[Racer X]

kap, almost all vehicles have either a neutral safety switch, or a clutch safety switch. If an automatic vehicle has the shifter linkage out of adjustment, you will get just that sort of occurance. The transmission was actually in reverse, but the indicator said park, and the safety switch (starter interlock, or whatever the manufactuer called it on that vehicle) was maybe somewhere in between, or was actually indexed for the reverse positionb, so it wouldn't start.

The clicking in the gearbox may have been that switch in the transmission partially engaging, or maybe a relay trying to trip while some other switch was cutting off the output or some such thing. I would have to look at a wiring diagram to make an educated guess. But the transmission shift linkage is a dead giveaway to something involving a starter interlock situation.

That is why on some older vehicles, or ones that are a wee bit out of adjustment, you have to wiggle the shifter as you try and crank the engine over.

[kap]

Racer X,

Your assessment makes absolute sense to me tho' I am no car mechanic. In retrospect, my S/O does jiggle the shift lever from time to time to ascertain that the gear is properly engaged. I just never thought that it would associate with the battery. I don't care to drive her car because there isn't much room to wiggle and the front seats are so uncomfortable so I have never really paid much attention. My car is a good and reliable 1987 Honda Accord LX and I love it!

Kap

[Racer X]

Shift levers/floor shifters have detents so you can do it by feel, but when the linkage/cable isn't adjusted to coincide with the detents, you can get these sorts of things. I am not saying that this is what's wrong, but it is more common than you may know. this sort of thing can be a cause for someone driving down the road and their reverse lights are on. It can be a bad switch, or if something isn't adjusted right, the switch thinks the car is in reverse.

[kap]

Racer X,

I will take the info with me and compare to what my mechanic's assessment. Will post follow-up. Thanks!

Kap