Good battery, Sluggish start

[crreed67]

I have a 2022 Cub Cadet Pro Z 960s KW not a year old yet with 58 hrs on it. Always garage kept. After sitting for a week or so between mows it acts like the battery is low or bad and is hard to turn over. Once it stars everything runs just fine. I can then turn it off for a bit, a few hours or so and it starts just great. It's after it sits for a few days is when it starts acting like it's got a dying battery. I've checked for a parasitic drain and found none and checked the battery voltage after a week of sitting and it is at 12.8V not running. What else am I missing or what should I check next.

 

[5030]

Load test the starting battery with a carbon pile load tester and report back... Me thinks you have a bad battery. 12.8 volts is basically low.

 

[2manyrocks]

My guess is it has a lawn mower sized battery that sat over the winter and now the battery is shot. You may want to invest in a battery maintainer charger for next winter. I keep mine charged with a 12v solar panel system. Saves on having to replace batteries and my battery is always charged.

 

[5030]

If you fully charge the lawnmower battery and then take it out of circuit (remove the negative terminal), the battery will be fine in the spring. I do that with my farm tractors that sit all winter in the barn and the lawn mowers as well.

Flooded cell batteries typically loose about 5% of the total charge from parasitic loss monthly.

 

[crreed67]

I've never had one do this over the winter before, especially being less than a year old. Could be though. I'll give it a load test and report back. Be a couple of days though. They're calling for light snow here tomorrow morning so I'll give it a day or three to warm back up.

 

[dodge man]

I agree, load test it.

 

[grsthegreat]

If it passes an actual load test, add a battery disconnect switch on battery.

 

[5030]

If it passes an actual load test, add a battery disconnect switch on battery.

What I use on everything.

 

[LittleBill21]

Load test the starting battery with a carbon pile load tester and report back... Me thinks you have a bad battery. 12.8 volts is basically low.

12.7 is a fully charged battery if sitting with no charge.... no idea why you think 12.8 is a low battery

 

[LD1]

12.7 is a fully charged battery if sitting with no charge.... no idea why you think 12.8 is a low battery

Agree

 

[LD1]

Could be the temp when trying to start it?

Anymore, those cheap little mower batteries are a 1-2 year lifespan. They seem to need replaced more and more frequently anymore

 

[LS Tractor Owner]

12.7 is a fully charged battery if sitting with no charge.... no idea why you think 12.8 is a low battery

The battery can show 12.8v just sitting there.....
Put a load on it and it can drop to 8 or so volts.... just a bad battery. Take the load back off and it jumps back to 12+v.

I have a battery sitting in the shed right now that shows 12.6 v..... it will run my little transfer pump (which only draws about 1/2 an amp) without a problem. Hook up a starter or high amp device.... nope - won't do it.

Load test is the only way to see if it's bad....

 

[/pine]

When it is slow cranking...feel all the connections in the starter circuit for heat...including the battery terminals themselves and especially the ground cable on the frame...

 

[LittleBill21]

The battery can show 12.8v just sitting there.....
Put a load on it and it can drop to 8 or so volts.... just a bad battery. Take the load back off and it jumps back to 12+v.

I have a battery sitting in the shed right now that shows 12.6 v..... it will run my little transfer pump (which only draws about 1/2 an amp) without a problem. Hook up a starter or high amp device.... nope - won't do it.

Load test is the only way to see if it's bad....

a sulfated battery will not sit at 12.8 not on a charger, for more then a week, sorry I have seen enough dead sulfated battery's to know, once you put one hit on the starter that battery won't come up over 12.4- 12.5

do i still think you need a load test? sure.

 

[grsthegreat]

I work with battery problems all the time with my generator service work. Homeowner says…not the battery, its showing 13 volts. But i place a load bank device on it and draw 1/2 of the cild cranking amps and ….. 8 volts. The built in charger is whats reading 23vdc output, but only 2.5 amps. The generator could suck down 200 amps turning over.

i have a carbon pyle tester snd a Midtronics electronic tester. Saves alot of discussion.

 

[LittleBill21]

I work with battery problems all the time with my generator service work. Homeowner says…not the battery, its showing 13 volts. But i place a load bank device on it and draw 1/2 of the cild cranking amps and ….. 8 volts. The built in charger is whats reading 23vdc output, but only 2.5 amps. The generator could suck down 200 amps turning over.

i have a carbon pyle tester snd a Midtronics electronic tester. Saves alot of discussion.

notice where i said not on a charger. your saying you see 13v resting voltages off a charger?

 

[grsthegreat]

notice where i said not on a charger. your saying you see 13v resting voltages off a charger?

Yes, all the time. The generac generators have built in chargers. 13.2v when working is normal resting voltage.

 

[crreed67]

Ok. I used one of these,

Clore Automotive Solar 1852 100 Amp Battery Load Tester​

, and when I hit the switch the top of the needle went into the yellow to about the number 10 plus one hash mark. When I started the motor the needle went to around 14 in the green so I reckon the charging system is working. Not sure about the load test part where it dropped into the yellow. Good? Bad? OK? I'm not sure what this means as to if the battery needs replacing or not. The battery is a 12-Volt Absorbent Glass Mat (AGM) Battery - 230 CCA. Cub Cadet OEM Item#: 725P17130.

 

[grsthegreat]

Your supposed to test load at 50% of listed CCA, so your battery is probably ok. There has to be some source of parasitic draw? That test shows battery dropped to nearly 11 volts under load, but thats not too awful, and should have been enough to turn motor over. Alot of times i test trouble battery it will drop to 8-9 volts. When you tested it this time, did unit start? You may have to retest it after it sits for a week, as thats when you stated you have issues.

i also use a clamp on dc amp tester to check for parasitic draw down. Need one that can register even a slight draw. My Fluke works great.