battery draws down

-
fl 71

fl 71

Well-Known Member
Joined
Apr 9, 2011
Messages
644
Reaction score
822
Location
Milwaukee Wi
Please don't besmirch me but am having a problem with my 73 Corvette. Rebuilt the original engine and reinstalled. New Battery and Power Master starter. When starting the car with a full charge on the battery and engaging the starter for less than 30 seconds the battery goes to 1/2 charge and engine turns over slowly. With that kind of a draw you would think something would be quite hot however the wires to the starter, the starter and the solenoid remain cool to the touch however the wire that runs from the solenoid to the starter post gets a little warm. Any thoughts would be appreciated. And yes I have Mopars as well.
Thanks
 
fl 71 said:
Obviously I'm not the best at electrical but if it was the starter wouldn't it be really hot to the touch?
Click to expand...
more than likely, yes - check the "born on date" on the battery.. what you are describing sounds more like battery than starter
 
fl 71 said:
Thanks all your thoughts are appreciated.
Click to expand...
Don't tell him that, as he might take it literal. :D

Sounds like a bad battery to me also.
The "dead":D giveaway is that it draws down that quick.
 
You can test the battery for a dead or bad cell using a battery hydrometer. They are pretty cheap. They look like a antifreeze tester with floating balls. This tool has taken a lot of guess work out of battery problems for me.
Yote
 
T
Yote said:
You can test the battery for a dead or bad cell using a battery hydrometer. They are pretty cheap. They look like a antifreeze tester with floating balls. This tool has taken a lot of guess work out of battery problems for me.
Yote
Click to expand...
Will pick up a hydrometer today. Was going to take it back to Advance Auto and have them check it however the test is only as good as the person doing the testing. Thanks all. Will let you know what I find.
 
When you return the battery under warranty for a new one have them test the new one before you take it.
 
What does "1/2 charge" mean? If you mean a dash voltmeter shows a drop from 12 V to 6 V, you need to locate the drop. Most commonly it is from corrosion right at the battery terminals (why even mini-marts sell battery brushes). Removing, brushing, and spraying with anti-corrosion should be an annual task on all vehicles in TN (bi-annual out West).

Crank while you monitor the voltage difference between BATT- and BATT+ lead posts (not the connectors). If that remains >12 V, then don't fault the battery. Similarly, if your starter doesn't get >8 V from input big stud to its case, don't blame the starter.
 
BillGrissom said:
What does "1/2 charge" mean? If you mean a dash voltmeter shows a drop from 12 V to 6 V, you need to locate the drop. Most commonly it is from corrosion right at the battery terminals (why even mini-marts sell battery brushes). Removing, brushing, and spraying with anti-corrosion should be an annual task on all vehicles in TN (bi-annual out West).

Crank while you monitor the voltage difference between BATT- and BATT+ lead posts (not the connectors). If that remains >12 V, then don't fault the battery. Similarly, if your starter doesn't get >8 V from input big stud to its case, don't blame the starter.
Click to expand...
Sorry for not keeping up the last few days but have been involved in a local fund raiser. What I meant as
1/2 charged was a crude way of saying when I hooked up the battery charger after trying to start the car the indicator on the charger was at 1/2 charge. Will try all the above suggestions on Monday. Thanks all.
Ed
 
Sounds like the battery might not be "holding a charge", usually due to "sulfated plates". The way I tell is if it won't crank the engine (all terminals good, voltage difference too low right at posts), and I put on the charger at 10 A and it shows "full charge" after <30 min, I know it isn't storing enough energy. I have Autozone load-test it and usually shows "bad battery". I also have a Battery Brain on all cars and when it trips too often (just dome lamp and such load), I have it tested and usually "bad". I bought ~4 batteries from Autozone a few years ago on the same day for various cars & trailer and at least 2 of them failed to hold a charge within 6 months (gold top, free replacement), and I recall one or two of the replacements did similarly. Seems there are/was a spate of bad batteries in the system. Since only ~2 battery plants in the country (supplying ~40 brands), might have been due to Billy-Bob on the night shift. Great advances lately in exotic batteries, but lead-acid ones seem to be getting worse, and much more expensive.
 
BillGrissom said:
Sounds like the battery might not be "holding a charge", usually due to "sulfated plates". The way I tell is if it won't crank the engine (all terminals good, voltage difference too low right at posts), and I put on the charger at 10 A and it shows "full charge" after <30 min, I know it isn't storing enough energy. I have Autozone load-test it and usually shows "bad battery". I also have a Battery Brain on all cars and when it trips too often (just dome lamp and such load), I have it tested and usually "bad". I bought ~4 batteries from Autozone a few years ago on the same day for various cars & trailer and at least 2 of them failed to hold a charge within 6 months (gold top, free replacement), and I recall one or two of the replacements did similarly. Seems there are/was a spate of bad batteries in the system. Since only ~2 battery plants in the country (supplying ~40 brands), might have been due to Billy-Bob on the night shift. Great advances lately in exotic batteries, but lead-acid ones seem to be getting worse, and much more expensive.
Click to expand...
Thanks. Checked last night and at the starter terminal and have 12.47 volts with the key in the off position.
Headed out to the garage now and am going to check the starter terminal with the key in the on and the start position and see if the voltage is being redirected some place else. Does this sound prudent?
 
If you determine that it is the battery, If it is a lead acid battery and you are going to replace it anyway, you might put a teaspoon of Epsom salt in each cell and charge overnight. I have , at times gotten an additional year from a battery by doing that. It seems to (clean ) the sulfate do plates.
Yote
 
You must log in or register to reply here.
-

Back
Top