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2010 Cub Cadet ltx 1040, new battery (Put in back in April), The battery doesn't stay charged, You can jump it and start it and let the charging system/alternator charge it up, but the next day, It goes from 12.5 volts to 8 to 10 volts. What do y'all think?
A bad cell? I was going to buy that NOCO GB40 starter/jumper but then i saw the price
Thanks in advance!

Try this: Get the battery charged back up to 12.7 volts, then disconnect the ground terminal. Let it set for the same amount of time, then check the voltage again. If it's down again, the battery is bad.

Auto parts store will tell you. Lawnmower batteries only have 90-day warranties. That lets you know how badly they are built.

cpurvis said:

Try this: Get the battery charged back up to 12.7 volts, then disconnect the ground terminal. Let it set for the same amount of time, then check the voltage again. If it's down again, the battery is bad.

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I'll try that, Thanks!

Scrubcadet10 said:

2010 Cub Cadet ltx 1040, new battery (Put in back in April), The battery doesn't stay charged, You can jump it and start it and let the charging system/alternator charge it up, but the next day, It goes from 12.5 volts to 8 to 10 volts. What do y'all think?
A bad cell? I was going to buy that NOCO GB40 starter/jumper but then i saw the price
Thanks in advance!

Click to expand...

I finally got around to charging the battery up today, got it to 12.8, and took the ground off. How long should i let it sit before checking it again? 1 day or a few days?

When I do a charge test I leave a pad & voltmeter next to the battery.
Every time I walk past I read the voltage & note the time.
In good condition the battery should go near 13 V and stay above 12.5 for around a month then discharge no faster than a couple of months.

To be of any use to you it definately needs to hold a charge for more than a week.

Mowers are tough on batteries both electrically and mechanically.
Add to that domestic mower users are really cheap so will happily use a totally buggered battery for decades till it gets to the point that the PTO starts cutting out or the mower will not have enough battery power to restart if turned off.
I stock 2 batteries
A Pb Ca mower battery for $ 95 ( cheaper than the discount auto stores who pay less for the battery than me )
A PVR AGM spiral cell battery for $ 295, never replaced one of these to date & all of them are still holding better than 13V after several seasons on commercial mowers.

The cub has a built in volt meter, showing 12.8, but i always use a meter to be sure its right.
Usually it takes about 4-5 days for the battery to get low enough where it cant turn the engine over.

You can check the voltage as often as you like. If it is still roughly 12.7 volts after a week with the ground cable disconnected, that means you have something draining the battery.

If it drops below 12v after a week, the battery is probably bad.

Or, you could just take it, fully charged, to an auto parts store and have them do a load test.

I went back down today, hooked the battery up, battery was reading 12.4 V. down from 12.8 yesterday. And whenever I'd turn it over it would go down to 11.8 volts.
So i took of the ground again and let it sit for a few more days.

I went back down today, hooked the battery up, battery was reading 12.4 V. down from 12.8 yesterday. And whenever I'd turn it over it would go down to 11.8 volts.
So i took of the ground again and let it sit for a few more days.

Okay, the battery has held steady for 2 days at 12.5 volts. down from 12.8V.
Do you think something is draining it? Could it be a short in the start solenoid, because really, the battery started draining when the solenoid started "Clicking" instead of starting.

I like to start from the starter motor and go backwards .
Do the following tests, regardless of the results from either of them as there can be more than one problem and you want to isolate where the problem lies.
Elimination of individual parts is important so you know by the end, the battery, solenoid & heavy power circuits are all in good order.

1) try to jump the starter motor directly from your car or truck.
Starter turns = starter good

2) do the same directly from the mowers battery
Starter turns = mower battery good
No turn = duff battery, recharge it & try again.

3) leave the - jumper lead on & remove the + jumper then try again
Starter spins = bad ground

4) Put the + lead on the battery connection on the solenoid & try again
Starter spins = bad power wire from the battery

In all cases above ( except the solenoid test ), put the + jumper directly on the + terminal of the starter motor directly first.
Then connect the - jumper to a good ground . I like to use the oil drain bolt,
Prepare yourself for a big flash when you do this which is why there is a solenoid in the starting circuit.

The solenoid isn't on the starter (if you mean to hook up to solenoid when you say starter) Or did i just mis understand you (i tend to do that sometimes:wink

Scrubcadet10 said:

The solenoid isn't on the starter (if you mean to hook up to solenoid when you say starter) Or did i just mis understand you (i tend to do that sometimes:wink

Click to expand...

That is right.
ON tests 1 to 4 you are connecting directly to the starter motor.
However when you make the high amp circuit you get a really big flash and that tends to make people jerk so if you are making the + connection to the starter terminal there is a better than average chance of jerking and contacting the starter body ( which is ground ) with the + jumper so you have then made a direct short.
If you hook up onto the starter first and then the ground it does not matter if you miss with the lead and touch some thing else.

Sorry took so long to get back to you.
Did the tests and battery is good, and starter is good.
A

Good stuff gets repeated. Sure wish this site would just create a few stickies on basics, including battery. Anyway ...

I have bought the 230AMP rider batteries for years and have them in 3 cars, right, 3 cars for weight reduction. Yes. this is not for most as these guys are sensitive to frequent starts. I run them year round including winter , here usually 25F-above. The point? They last if maintained, and have lasted the 2-3 years expected in cars and riders (lots of ruts.) I do cater to them, $25 new.

As Bert mentioned there are many good sites to help understand batteries. No one above mentioned (?) the use of bat hydrometers as a supplementary device which is cheap ($10) and can help reach conclusions . If one of the batteries is aged or otherwise suspect I use the hydrometer to measure the specific gravity after charging. Recently I got a hydrometer with a finer scale, not just "good", "fair", "bad" ( the little floats that rise when you draw out the electrolyte with the suction bulb have numbers on them). And I now use the ground rule of "50 points." As you check across the 6 cells note the readings. Variation of .50 across the 6 readings indicates a failed battery . This is also useful if you have a "repair" or "desulfate" function on your charger which may say "repaired" battery and read 12.8 v or above, but which registers a 50 point spread on the hydrometer. Recently this drill showed a failed battery which would not hold the 12.8v over a minute.

I got the solenoid put on this morning, cranked right up, and so far the battery is staying charged!!