Battery not charging
Thread Starter
Le Mans Master
Joined: Apr 2002
Posts: 5,726
Likes: 46
From: Waukesha WI
St. Jude Donor '15
Battery not charging
I seem to be having a problem with the charging system on my Dad's 86. The battery is a brand-new Optima Red. I can charge the battery with a normal charger in the garage and it *seems* to be OK...ie. I can start the car. After I start her up, drive into town and park some place she won't start. Luckily, I have a portable jump-pack to carry around.
Sometimes on a long drive (40+ miles) it will start again. The dash reads 13.5+ volts most of the time with 14.1-2 showing occasionally. I had a load test done at AutoZone (twice) and everything checks out. The only oddity is that under load the dash readout dropped to 8-9v. I know they put a major load on there but that seemed a bit low.
Right now I am leaning towards getting a new Alt. but I wanted to pick the Forum brain forst to see if I should check something else first.
Thanks!
Dale
Sometimes on a long drive (40+ miles) it will start again. The dash reads 13.5+ volts most of the time with 14.1-2 showing occasionally. I had a load test done at AutoZone (twice) and everything checks out. The only oddity is that under load the dash readout dropped to 8-9v. I know they put a major load on there but that seemed a bit low.
Right now I am leaning towards getting a new Alt. but I wanted to pick the Forum brain forst to see if I should check something else first.
Thanks!
Dale
Melting Slicks
Joined: Apr 2003
Posts: 3,110
Likes: 6
From: Red Sox Nation! RI
If your battery is load testing ok with no dead cells, I'd check your cables and connections for a clean solid ground. You can pull your alternator and have it tested for output, but sounds like a bad ground to me.
Safety Car
Joined: Jan 2006
Posts: 3,566
Likes: 4
From: Mt Laurel NJ
St. Jude Donor '06-'07
Have you tried putting a meter on the battery to see what in charge from the alt is? I would not believe the dash gauge. Could also be an issue w/ the starter or a bad/weak ground.
Good Luck
Randy
Good Luck
Randy
Thread Starter
Le Mans Master
Joined: Apr 2002
Posts: 5,726
Likes: 46
From: Waukesha WI
St. Jude Donor '15
I am not really sure how to check the quality of the grounds. The book shows 2 - one on the frame below the battery that looks to be in good shape with little corrosion or wire damage and another going to the engine that I can't really follow once it passes the valve cover and goes behind the engine.
I checked the resistance of the connection at the battery to the block and to the wire on the frame and both show <1 ohm. There also does not appear to be any major corrosion/damage on any of the wires to the alternator and battery.
I just remembered...I have a spare (working) Vette here (90) and I can probably just swap alternators to rule that out.
Thanks!
Dale
I checked the resistance of the connection at the battery to the block and to the wire on the frame and both show <1 ohm. There also does not appear to be any major corrosion/damage on any of the wires to the alternator and battery.
I just remembered...I have a spare (working) Vette here (90) and I can probably just swap alternators to rule that out.
Thanks!
Dale
Thread Starter
Le Mans Master
Joined: Apr 2002
Posts: 5,726
Likes: 46
From: Waukesha WI
St. Jude Donor '15
The voltage across the battery while running is 13.7-9 and the voltage between the neg. post and the back of the alternator is 14.1-3. The gauge was reading 13.7 - not too far off.
Team Owner
Joined: Mar 2001
Posts: 54,124
Likes: 30
From: Cincinnati, Oh USA
The dash voltmeter has significant error if the alternator isn't charging the battery and that is why you saw 8-9 volts, battery under load. If the alternator is not charging the battery the red battery symbol light on the dash will light. Also, I recommend that you remove the battery cables (neg first) and clean the cable lugs, battery terminals and the bolts until they are clean and bright and replace (neg last). Looking at the connected cables isn't good enough because the connection that counts is where the lug and batt terminal touch which cannot be seen.
You can tell the state of charge on the battery by measuring its no load terminal voltage. 12.0 volts and below, discharged. 12.9 volts and above, fully charged and linear in between. A discharged battery will not start your car. Always charge a discharged battery up overnight with a battery charger and do not rely on the alternator to charge the battery. Alternators get hot when charging a discharged battery and it shortens their life.
You can tell the state of charge on the battery by measuring its no load terminal voltage. 12.0 volts and below, discharged. 12.9 volts and above, fully charged and linear in between. A discharged battery will not start your car. Always charge a discharged battery up overnight with a battery charger and do not rely on the alternator to charge the battery. Alternators get hot when charging a discharged battery and it shortens their life.
Team Owner
Joined: Dec 1999
Posts: 34,873
Likes: 487
From: Lacey WA RVN 68-69
NCM Sinkhole Donor
Do a search on Optima or Red Top and you will find some members have have issues with Optima Red Top batteries.
The battery may be taking a "surface" charge but not be able to take a full charge. Did AutoZone do a load test with the battery in the car? Or did you take just the battery to them?
I would recommend taking the car to a reputable shop and have them check the battery and charging system with their equipment while the car is running. I'm betting you have a bad battery.
The battery may be taking a "surface" charge but not be able to take a full charge. Did AutoZone do a load test with the battery in the car? Or did you take just the battery to them?
I would recommend taking the car to a reputable shop and have them check the battery and charging system with their equipment while the car is running. I'm betting you have a bad battery.
Thread Starter
Le Mans Master
Joined: Apr 2002
Posts: 5,726
Likes: 46
From: Waukesha WI
St. Jude Donor '15
The test that Autozone ran was an on-car test - engine running. The second time they did a battery only test with the engine off and both times the tester said everything was ok.
I pulled the battery and charged it up overnight. The no-load reading is 13.3v. I was planning to take it over to AZ and see about doing an off-car load test a few times to see the result. If the battery tests OK then i am still lost. I can still swap a known good alt/bat from the 90 into this car for testing but I'd rather not.
As far as the reputation of Optima...I can understand it. I also have an Optima Red in my 90. The first lasted only 2yrs and when its replacement dies (no more warranty) I plan on just getting a normal cheap-o.
Thanks!
I pulled the battery and charged it up overnight. The no-load reading is 13.3v. I was planning to take it over to AZ and see about doing an off-car load test a few times to see the result. If the battery tests OK then i am still lost. I can still swap a known good alt/bat from the 90 into this car for testing but I'd rather not.
As far as the reputation of Optima...I can understand it. I also have an Optima Red in my 90. The first lasted only 2yrs and when its replacement dies (no more warranty) I plan on just getting a normal cheap-o.
Thanks!
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Thread Starter
Le Mans Master
Joined: Apr 2002
Posts: 5,726
Likes: 46
From: Waukesha WI
St. Jude Donor '15
Interesting... About 30min after I typed the above, the no-load voltage dropped to 12.8 with no help from me. I took it to AZ and their tester said it was fine. I returned it and got a normal batttey anyway - I just don't trust Optimas anymore.
Hopefully I will have good news to report after a few short trips around town.
Hopefully I will have good news to report after a few short trips around town.
Thread Starter
Le Mans Master
Joined: Apr 2002
Posts: 5,726
Likes: 46
From: Waukesha WI
St. Jude Donor '15
So far the new battery seems to be working. I have made a few short trips around town with many restarts and all seems well for the moment. Hopefully this is the end of the line for this gremlin 
Thanks!
Thanks!
Drifting
Joined: May 2005
Posts: 1,336
Likes: 12
From: Chicago Executive Airport, formerly known as Palwaukee
No-IL Events Coordinator
St. Jude Donor '12-'13-'14-'15-'16-'17
I just ran into the exact same problem with my 96 CE LT4. I bought the car new and it has 86,000 miles on it.
I put an Optima Red Top in it about three months ago. Then I started having starting issues. Took the Red Top out twice to have the battery company test it. Tested good both times. I tested the battery myself. Would always test GOOD!
Did a search here and everyone said to clean the connections. Well, what do you know?
Cleaned all the connections. Including the two smaller cables coming off the positive end of the battery to two junction blocks. Took the starter down also and cleaned those connections up.
Car starts faster than when it was new. Charges properly. My apologies to the Optima folks for thinking I had a defective Red Top.
SAVE THE WAVE!
I put an Optima Red Top in it about three months ago. Then I started having starting issues. Took the Red Top out twice to have the battery company test it. Tested good both times. I tested the battery myself. Would always test GOOD!
Did a search here and everyone said to clean the connections. Well, what do you know?
Cleaned all the connections. Including the two smaller cables coming off the positive end of the battery to two junction blocks. Took the starter down also and cleaned those connections up.
Car starts faster than when it was new. Charges properly. My apologies to the Optima folks for thinking I had a defective Red Top.
SAVE THE WAVE!
