Bad battery or generator?

S

Solo_909

Senior Member
Hey guys so my 35 has been acting up lately. It’s been not wanting to start lately and the battery has been dead in the morning and needs a jump. I did like a few months ago have the same issue so I took my battery in to have it tested and they said it was fine however it’s been getting worse. The battery is a yellow top optima and is only about 3 years old so I don’t know if it would be that.

How do I tell what needs to be replaced? The generator and that battery are about the same price so I want to make sure I’m not blowing money if I don’t need too.

Thanks ��������
 
Borrow someones meter.
During the day, if shut off, will it restart? That would point to the battery. Also, now that I think about it, just a jump in the morning won't keep it running if the the charge system is not functioning; given that as you say the battery was dead, to begin with. It is true though, that you should expect more from an Optima.

Another cause to consider is a draining short causing a loss overnight. You may want to run it. Then when parking disconnect the Optima then see what morning brings Good Luck!
 
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A bones said:
Borrow someones meter.
During the day, if shut off, will it restart? That would point to the battery. Also, now that I think about it, just a jump in the morning won't keep it running if the the charge system is not functioning; given that as you say the battery was dead, to begin with. It is true though, that you should expect more from an Optima.

Another cause to consider is a draining short causing a loss overnight. You may want to run it. Then when parking disconnect the Optima then see what morning brings Good Luck!
Click to expand...


Great questions and ideas! So after the jump it will run until I turn it off then it will need another jump. It did however yesterday morning die after I jumped it. But that happened once and didn’t happen again could have just been the carbs.

So let’s say I jump it and drive it for a little bit and then when I park it I disconnect the battery. In the morning if it’s dead thy would be the battery if it has a charge it means I have a live wire some where?

Thanks!
 
Perhaps to ensure the battery is initially fully charged. Then monitor its charge before start attempts and after running. And before and after park periods to confirm battery condition. Then move on to charging circuit if battery is ok. As if 3 years old should still be ok! A multimeter is a useful tool to own when playng with old cars.
Phil NZ
 
With everything turned off, unhook the hot lead off battery terminal, then jump a test light from terninal to clamp.

Any glow at all is a resdual drain.

If you have a modern radio, it may be the cause of making it glow too, so then pull the fuse to the radio.
 
pooch said:
With everything turned off, unhook the hot lead off battery terminal, then jump a test light from terninal to clamp.

Any glow at all is a resdual drain.

If you have a modern radio, it may be the cause of making it glow too, so then pull the fuse to the radio.
Click to expand...

What does a residual drain mean? I don’t have a radio or any add ons.
 
Solo_909 said:
So let’s say I jump it and drive it for a little bit and then when I park it I disconnect the battery. In the morning, if it’s dead that would be the battery. If it has a charge, it means I have a live wire somewhere?

Thanks!
Click to expand...

That is a yes, what I meant. However both pooch and Phil Gillespie make strong valid points. They require equipment you might not have, but ask around town. I'm sure if you find someone with them, they will be happy to lend a hand!

The word on newer Optimas is disappointing by some, also the method of charging seems to be in dispute. :confused:
Some insist on a Optima designed charger. Others use conventional means with no complaints.
 
If the Optima has been discharged it is difficult to recharge it with a generator or normal charger. There have been a number of threads on the procedure to charge an Optima.

Note: apparently this is just an issue for some uses and not all!
 
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Maintenance free batteries don't like to set idle any better than wet cell types do. Charging procedure is the same. You cant check electrolyte on a maintenance free so the only way to do a test is to charge it and do a high rate discharge test. If it passes that, it's good to go. A generator is taxed harshly when a battery is going south. It has to work overtime and that's not good for it, especially so on an old 3-brush type.
 
JSeery said:
If the Optima has been discharged it is difficult to recharge it with a generator or normal charger. There have been a number of threads on the procedure to charge an Optima.
Click to expand...

I had the optima totally dead in my A, hand crank started it, 20 minutes later it would start the car on its own--- the 3 brush cars generator just knows how to put out amps to its limit

What does the dash ammeter say
Is the charging system stock --- if so perhaps the cutout stuck, charge while running, discharge when stopped
 
Thanks for the info. So would it be better to go with a normal battery since the old generator doesn’t have it in her to fully charge the optima?

I’m going to take the battery to a local auto store not autozone and see if they can do a charge and rapid discharge test and see why they say.

My gauges on my dash have all been changed so I can only see volts. When driving I’m around 14, idle at around 12, and lately when turning the key on 8 or below when it needs a jump.
 
Generator is just fine with optima--- my last one went 16 years without charging it except by driving--- and the model a has a lower amperage generator--- and I use halogen bulbs with no charging problems

Do you have a stock system---- you are giving 12 volt system numbers
 
So I took the battery to a shop and everything tested good. Even the drain test showed good. I bought a circuit tester so I’ll see if I have a drain next.


Any ideas on how to find the exact wire? I’m
Not really sure how the circuit tester works. Do I just hook it up to a ground touch the metal tip to the removed fuses and if it lights up that’s where a wire is live?
 
Kurt in NJ said:
Generator is just fine with optima--- my last one went 16 years without charging it except by driving--- and the model a has a lower amperage generator--- and I use halogen bulbs with no charging problems

Do you have a stock system---- you are giving 12 volt system numbers
Click to expand...

Mallory distributor, msd coil, and new wireing harness. Everything has been converted minus the generator.
 
pooch said:
With everything turned off, unhook the hot lead off battery terminal, then jump a test light from terninal to clamp.

Any glow at all is a resdual drain.

If you have a modern radio, it may be the cause of making it glow too, so then pull the fuse to the radio.
Click to expand...


Okay so I bought a circuit tester. The guy there said you test the ground and it if lights up there’s a drain. If I remove the ground from the battery and touch the tester to the ground post and ground cable the light comes on. If I remove the positive cable from the battery and and keep the ground connected while touching the positive post and the positive cable with the tester the light comes on. So which is correct?
 
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Hook it between the cable and battery I use a test light if the test light light up then you have draw
But on the newer car you have the radio and ecm will draw a little
 
The 1935 Ford vehicles had a positive ground 6-volt system with a 3-brush generator with a cut out relay up on top. If this thing has a 12-volt negative ground system then it has been modified. Since they don't make a 12-volt 3-brush generator, I'd be suspect that is has either a 12-volt generator with a 3-pole voltage regulator like was used back in the 50s & 60s or it has a 12-volt alternator which likely has a built in VR with a single wire coming out to connect to the bus for charging.

Troubleshooting procedures are different so folks have to know what it has to be more specific.
 
.
Proper charging voltage while driving at or above 20 mph is 7.3v OR 14.6v ( depending whether 6v or 12v battery).

Less than 20 minutes or less than 7.3v OR 14.6v it will not attain full charge.

Rest voltage of a fully charged battery is 6.3v or 14.6v.

Talk of bad Optimas ONLY refers to a 1 year period where the internal straps would get broken in shipping. Otherwise, Optimas use similar chemistry to lead acid wet cells.


.
 
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Okay so I took my “generator” to a local old school auto electric shop to have tested and he told me I have an alternator in the generator body. I forget the company name but he’s going to test it.
 
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