Do Amps matter or is voltage more important?

[Davison]

So I have a few cars on battery tenders. One is a 1972 440 GTX auto. Now that winter is over I have checked the voltage. The batteries show 12.6 to 12.8 Volts. I just bought a battery tester. It too shows good voltage, but the CCA are in the 200 range and not 500. So it comes up with the message: REPLACE BATTERY. What do you think? I really don't want to waste my money on new batteries but I also don't want to be stuck at the side of the road. I only drive these cars above 40 degrees so CCA was of little concern, but should I be concerned? I try to drive them twice a month for 15-30 miles each time in nice weather. Thanks.

 

[PurpleBeeper]

Amps matter. You need a new battery

 

[R413]

Many times these testers give false readings. What size are the wires you connect to the battery? Does it have an amp clamp to put around a cable?

Does the car start good? Both cold engine and after parked hot for 15-30 minutes with hood closed? That's the best test, if it starte the car it is in.

He never said the car won't start, just what the tester said.

Does it have a clamp like this. It will give a true amp draw of the system.
DIGITAL CLAMP METER – clamp on amp meter – Volt Ohm Amp tester | eBay

 

[Demonic]

(Snip0

Does it have a clamp like this. It will give a true amp draw of the system.
DIGITAL CLAMP METER – clamp on amp meter – Volt Ohm Amp tester | eBay

Thats crazy cheap for an AC/DC multimeter that ACTUALLY does DC amps. I’d be wary.

 

[Nacho-RT74]

You can get 3 guys pushing a car but not strong enough to move it.

The ammount of guys are the voltage… their strength is the amperes.

Maybe that’s the easy way to understand it

 

[dadsbee]

A useless battery can still show that it has over 12 volts, but load testing is the only way to see if it's actually good. This is an uncharged Odyssey PC925 after a script case install. Charged to 100% they pull 1000CCA.

BTW, you can probably thank that tender for pooching your battery over the Winter!

 

[Cranky]

If you have a stock style starter, your battery probably isn't going to start the car but if you have a mini starter, it probably will....at least in my experience. The newer mini starters don't require big amps.

 

[RemCharger]

Pinching pennies and running old toasted batteries doesn't do your charging system any favors either

 

[Cranky]

Pinching pennies and running old toasted batteries doesn't do your charging system any favors either

Usually overheats the alternator....

 

[RJRENTON]

So I have a few cars on battery tenders. One is a 1972 440 GTX auto. Now that winter is over I have checked the voltage. The batteries show 12.6 to 12.8 Volts. I just bought a battery tester. It too shows good voltage, but the CCA are in the 200 range and not 500. So it comes up with the message: REPLACE BATTERY. What do you think? I really don't want to waste my money on new batteries but I also don't want to be stuck at the side of the road. I only drive these cars above 40 degrees so CCA was of little concern, but should I be concerned? I try to drive them twice a month for 15-30 miles each time in nice weather. Thanks.

CCA (Cold Cranking Amps) is a measure of the battery's ability to produce the power required to start the engine under adverse conditions (cold weather, high compression, thick oil, etc.). You should consider purchasing a "battery tender", a low amperage charging device to keep your battery at its full capacity during storage. 12v lead acid storage/starting battery for vehicle service produce approximately 12.6 volts. The battery's specific gravity, a measured with a hydrometer of the battery's acid concentration, is the best determination of the battery's state of charge, with 1.260 -1.270 being fully charged. Hope you understand........
BOB RENTON
""

 

[R413]

@dads bee has a real load tester, see he large cables and bent holes for aor to,the load device? That's a real battery test.

 

[R413]

Thats crazy cheap for an AC/DC multimeter that ACTUALLY does DC amps. I’d be wary.

The amp part is built into the top with no cables for it. But this cannot test a battery, it had no load tester in it, it tests the amps flow in the systems on the vehicle.

So he doesn't have one of these.

 

[toolmanmike]

@dads bee has a real load tester, see he large cables and bent holes for aor to,the load device? That's a real battery test.

Well, yes and no. That is a toaster ribbon tester. The resistance is only like 100 amps and the load is estimated. A carbon pile load tester is more accurate and can load to 500 amps which will test a 1000 a/hr. battery.

 

[WileE]

So I have a few cars on battery tenders. One is a 1972 440 GTX auto. Now that winter is over I have checked the voltage. The batteries show 12.6 to 12.8 Volts. I just bought a battery tester. It too shows good voltage, but the CCA are in the 200 range and not 500. So it comes up with the message: REPLACE BATTERY. What do you think? I really don't want to waste my money on new batteries but I also don't want to be stuck at the side of the road. I only drive these cars above 40 degrees so CCA was of little concern, but should I be concerned? I try to drive them twice a month for 15-30 miles each time in nice weather. Thanks.

CCA (Cold Cranking Amps) is a measure of the battery's ability to produce the power required to start the engine under adverse conditions (cold weather, high compression, thick oil, etc.). You should consider purchasing a "battery tender", a low amperage charging device to keep your battery at its full capacity during storage. 12v lead acid storage/starting battery for vehicle service produce approximately 12.6 volts. The battery's specific gravity, a measured with a hydrometer of the battery's acid concentration, is the best determination of the battery's state of charge, with 1.260 -1.270 being fully charged. Hope you understand........
BOB RENTON
""

First sentence of the topic. That's ok, Bob, sometimes I get lost by the time I throw in some comment.

 

[GTXDAN]

Many times these testers give false readings. What size are the wires you connect to the battery? Does it have an amp clamp to put around a cable?

Does the car start good? Both cold engine and after parked hot for 15-30 minutes with hood closed? That's the best test, if it starte the car it is in.

He never said the car won't start, just what the tester said.

Does it have a clamp like this. It will give a true amp draw of the system.
DIGITAL CLAMP METER – clamp on amp meter – Volt Ohm Amp tester | eBay

That meter only does AC amps, not DC. That's why it's so cheap. You won't find one for DC amps that cheap. If your battery has been on a battery tender all winter and it only shows 12.6-12.8V either the battery is bad or the tender is bad. You need a tester like https://www.forbbodiesonly.com/moparforum/members/dadsbee.28641/ has to load test the battery.

 

[twecomm]

Batteries can act weird if on verge of going bad, can seem OK one minute and next time nada, they don't last forever.. 12.6 is indeed normal battery voltage with no load. They may show proper voltage but not have current capacity to be able to crank sufficiently to start. If your battery is able to crank the car and start it reliably and takes a proper charge from your alternator to replenish the discharge from cranking while driving for a while , I think there is no reason for concern unless you have some sort of problem with your cars charging system.
I put my car in winter storage for 5 months and never bother with any type tender charging, I just disconnect the battery for safety sake. When I take it out of storage In spring, it's a sure thing that any gas in the carb bowls has evaporated. I have a stock mechanical fuel pump. To avoid endless cranking to pump gas back to carb bowels, a small splash of gas directly in the carb and it always has right up on first crank. My 2 cents, others may not agree...

 

[AR67GTX]

A useless battery can still show that it has over 12 volts, but load testing is the only way to see if it's actually good. This is an uncharged Odyssey PC925 after a script case install. Charged to 100% they pull 1000CCA.
View attachment 1849572
View attachment 1849577

BTW, you can probably thank that tender for pooching your battery over the Winter!

These are only $20 at Harbor Freight (or they were a year ago). For that price you can’t hardly afford to be without one. I’ve also read in several places that they work a lot better than most the circuit board electronic load testing gizmos.

 

[RJRENTON]

That meter only does AC amps, not DC. That's why it's so cheap. You won't find one for DC amps that cheap. If your battery has been on a battery tender all winter and it only shows 12.6-12.8V either the battery is bad or the tender is bad. You need a tester like https://www.forbbodiesonly.com/moparforum/members/dadsbee.28641/ has to load test the battery.

I have a DC clamp on meter.....a Pacer Amppac.....very accurate....with the proper adapter it can read 400+ Amps DC.
BOB RENTON

 

[toolmanmike]

I have a DC clamp on meter.....a Pacer Amppac.....very accurate....with the proper adapter it can read 400+ Amps DC.
BOB RENTON

Not even good enough for a proper starter draw test. And, it can't load test a battery.

 

[RJRENTON]

Not even good enough for a proper starter draw test. And, it can't load test a battery.

But it can show the amperage the starter motor consumes, thru the positive cable wire, plus misc electrical loads that occur during cranking. A battery load test using a variable load resistor (carbon pile) draws a given amperage at a given amount of time, while measuring battery terminal voltage at the same time the amperage draw is measured. It usually determines the battery's condition......whether sulfation is occurring. A common test: 400 amp draw, and terminal voltage remains at or above 10.5 volts.......
BOB RENTON