12volt starting battery

[jlscjs]

Started to go out in the boat but starting battery was dead, I put the charger on it for a few minutes and got it to start. Took the boat out and ran it across the lake for a bit and brought it back, plugged the charger into it and it showed 13.2 volts but only 57 % charged. Left it on for a few hours and it still read 13. 2 volts and 57 % charged. How do I tell if the battery is any good and is 13.2 volts the correct amount for a fully charged battery?

 

[alldodge]

Assuming its a lead acid bat, and if the bat ever goes dead it can damage the bat. Leave the charger on over night then remove the charger. Measure the voltage with charger off, and let it sit for 30 minutes to an hour. If its not up to at least 12.5V the bat has probably been damaged

 

[Texasmark]

Autozone or Wallyworld to name a couple have battery load testers and can help you so there is no doubt when you are ready to go out next time.

 

[Scott Danforth]

agreed..... take the battery and have it load tested.

the percent charge is simply basing it on a voltage. 12.0 volts is 100% discharged, 13.2 volts is partially charged, 13.6 volts is fully charged.

 

[alldodge]

^^^^ Ahhh No not so

Also load testing a bat which can not be changed to at least 12.5V would not provide much info

 

[Lowlysubaruguy]

Hydrometer readings are the best way to check a liquid filled marine batteries ability to take a charge if you have a weak cell after charging it will show here. Most parts stores sell really cheap ones that work just fine. Most marine batteries will pass most other plug and play type battery testers a carbon pile load tester with a volt meter is another good test but also can be misleading if it passes.

 

[Texasmark]

Hydrometer readings are the best way to check a liquid filled marine batteries ability to take a charge if you have a weak cell after charging it will show here. Most parts stores sell really cheap ones that work just fine. Most marine batteries will pass most other plug and play type battery testers a carbon pile load tester with a volt meter is another good test but also can be misleading if it passes.

Gotta drill a hole if each cell if you want to Hydro test a sealed battery!

 

[Texasmark]

^^^^ Ahhh No not so

Also load testing a bat which can not be changed to at least 12.5V would not provide much info

Well if you can only get it to 12.5 it's DOA anyway so no need to load test.

 

[QBhoy]

Hi
once a standard battery goes dead and is well used...normally it will never recover to its full health. Especially if it’s a dedicated starter battery as in one designed for high CCA and not leisure use and gradual release.

 

[jlscjs]

Well the battery is dead, since this is the first time I've had to replace it what is a good replacement size? It currently has a group 24 with 1000 mca and 135 minutes reserve Everstart in it , the motor is a 50hp.

 

[Texasmark]

What's in it is fine. 50 hp doesn't need a lot to start. What happens in some instances is that the boat sits for long periods with out use and the owner doesn't charge the battery before going out. Hence there will be some discharge of the battery and a smaller battery may not have enough reserve, so one buys a larger battery than necessary to cover that instance.