BATTERY

[randy greenbaum]

Hello All,

I'm having a problem with the battery on my '64. Car hasn't been driven for about 3 weeks. Bat reads nearly 15 volts but will not turn over the motor. Interior lights work good until I hit the ignition. Horn barley croaks. The Delco battery is not very old. I put it on the charger for 4 hours and still won't turn over the motor. When I reach down to see if the hot lead from the bat to the starter is secure, and the back of my hand touches an ignition shield, I get a jolt of current. Any thoughts will be greatly appreciated.

Thanks, Randy

[John D.]

Re: BATTERY

Randy,Remove the negative cable and clean it and the battery cable with the usual wire brush. Then check to see if it is properly grounded on the other end. Sounds like your body completed the ground circuit instead of the battery and wiring. Of course it could be a starter problem. Try jumping the starter to see if it works. Maybe the solenoid. Since the interior lights dim though when you try and start it I suspect it's really something simple as mentioned. John

[Louis T.]

Re: BATTERY

Hi Randy,

I agree with John's thoughts and I would follow his suggestions, as well.

That said, was the "15" Volts a typo? While a properly operating charging system will maintain a voltage of 13.5-14.5 Volts or thereabouts at some specified engine speed, I've never seen a battery at rest with anything over 12.5 Volts.

You didn't mention what your battery charger's Amp meter (all but trickle chargers should have one) was doing during the four hours you were charging. Most start with the needle in the 3+ Amp range and slowly decrease as the battery gets charged over time. An automatic charger will actually shut itself off when the battery is full; a manual charger will simply read a very low number. My experience has been that the Amps will never drop close to zero on a bad battery.

Also, is this a sealed battery, or can you check the electrolyte solution level in each cell? (Remember to use distilled water.)

Finally, if all else fails, swap the battery with one in your daily grocery-getter, try starting both, and see what happens.

Louis

[randy greenbaum]

Re: BATTERY

Thanks guys for your input.

Louis, I'm getting 14.5 or so at rest on the sealed Delco. I'm not sure what the norm is, but if my 40 Harley only has 12.5v in it's battery, then that is concidered a bit low. Normal for it would be around 13v or a bit over and anything below 12.3v and the bike won't run right.

[Terry M.]

Re: BATTERY

Normal battery voltage for a fully charged lead-acid battery at rest is 12.5 +/- .3 volts. Anything more or less is cause for further testing of the battery.

The only accurate way to test the condition of an automotive battery is with a load test. Many FLAPS (Friendly Local Auto Parts Stores) will do that test free if you bring the battery to them. Some have the capability to test the battery while it is installed in the car -- a telephone call will tell you which, if any, they can do. In the later case the equipment may also be able to check the entire charging system -- again ask. Be cautious in that while it is one thing for them to have the machine, it is quite another for them to have someone who knows how to operate it. One is more likely to find employees with that skill during the week than on weekends -- but questioning the people, especially face to face, will reveal what they have and what they know. If you see the deer-in-the-headlights look, go elsewhere.

Most auto shops also have the equipment to check the charging system, and will sometimes do so for a nominal fee, and sometimes for free if you are a regular customer.

The modern computer-controlled charging system test machines (called VATS = Volt Amps Testing System) will give one a print-out stating battery and alternator condition. They are easy to operate with less than a half-hour of training. The down side is that they cost around 5K. That puts them out of reach of most DIY folks. Older manual machines are readily available for a Benjamin or less, but they require a couple of brain cells to operate properly.

[Jack H.]

The rule of thumb...

for a fully charged, lead acid, automotive battery is 2.2V per cell. With six cells in series, that works out to 13.2 VDC. But, different battery's have slightly different efficiency silhouettes and internal self-discharge is a way of life meaning the fully charged silhouette doesn't last that long...