Go Back   Winnipesaukee Forum > Winnipesaukee Forums > Boating > Boat Repairs & Maintenance
Home Forums Gallery Blogs YouTube Channel Classifieds Links Calendar Register FAQDonate Members List Search Today's Posts Mark Forums Read

Reply
 
Thread Tools Display Modes
Old 06-05-2021, 07:52 AM   #1
Garcia
Senior Member
 
Join Date: Aug 2017
Posts: 400
Thanks: 90
Thanked 188 Times in 115 Posts
Default Boat battery charging time

For the first time I can remember the battery in my boat drained. I am guessing it is due to the bilge running for the couple weeks the boat had been sitting at the slip. I used a jump pack to get it going, ran it over to the island (10 minutes) where it sat for the weekend. Dead again Monday. Jumped it, brought it back to the slip (10 minutes), left bilge and everything off and found it dead again on Friday.

The battery was new at the start of the season last year. It's on a trickle charger now. Battery seems to test OK.

Before I worry too much about something drawing power (I have checked all the usual suspects), adding a back up battery or solar charger, I started thinking - once a battery on a boat is drained, how long does the boat have to run to fully charge it back up? I am guessing it takes a long time and the 10 minutes it ran did basically nothing to recharge the battery; my hope is that using the battery charger and bringing it back up to 100% will resolve the issue.

Anyone know how long a 90 HP Mercury outboard needs to run to fully charge up the battery?

I have to say those little portable jump packs are great - I keep one in each of my vehicles.
Garcia is online now   Reply With Quote
Old 06-05-2021, 08:34 AM   #2
thinkxingu
Senior Member
 
thinkxingu's Avatar
 
Join Date: Jul 2014
Posts: 4,423
Thanks: 1,075
Thanked 1,432 Times in 857 Posts
Default

When I spoke to Nick last week (mentioned on another thread), he said that boat batteries essentially never get fully recharged through normal use because the last 10 percent or so takes hours to finish. That was why he said, for longevity, a trickle charger is essential.

The question now is whether your battery was damaged by being so discharged so long.

Sent from my SM-G950U using Winnipesaukee Forum mobile app
thinkxingu is offline   Reply With Quote
The Following 2 Users Say Thank You to thinkxingu For This Useful Post:
Dave R (06-09-2021), Sam603 (06-09-2021)
Old 06-05-2021, 09:01 AM   #3
mswlogo
Senior Member
 
Join Date: Jun 2014
Posts: 371
Thanks: 130
Thanked 155 Times in 92 Posts
Default

10 min really isn’t enough, but it shouldn’t be stone dead the next time you use it.

Lead Acid batteries don’t like being left discharged.

I always disconnect battery for winter.

“Trickle charger” may not cut it. You want a “smart charger”. It can also tell you if the battery is any good when it’s done.

Chargers like these have brought batteries back that I thought were surely gone. My first battery lasted like 3 years. My 2nd battery (after buying a similar charger) lasted 14 years, and was still good when I sold the boat.

https://www.amazon.com/gp/product/B07CZG91FV

It’s also possible you have a leak in the boat. A crude old test I used to do was use a tail light bulb and put it in series with the (charged) battery connection. If it lights up, you have a significant leak.

But today I’d use an amp meter like this one. One of my favorite tools.

https://www.amazon.com/gp/product/B001TCWL1E
mswlogo is offline   Reply With Quote
Old 06-05-2021, 09:57 AM   #4
Garcia
Senior Member
 
Join Date: Aug 2017
Posts: 400
Thanks: 90
Thanked 188 Times in 115 Posts
Default Thanks!

The battery had enough juice to power the trim and turn the bilge on, but not enough to start the boat (didn't turn over). It's on the charger now and once it's fully charged I'll test the battery.

The two weeks it was on the slip is the longest stretch it will sit all season. From now until October someone will be using the boat every couple of weeks. I am hoping the issue was rain which caused the bilge to run and drain the battery and the battery never got charged up enough to maintain itself.
Garcia is online now   Reply With Quote
Old 06-06-2021, 02:28 PM   #5
ITD
Senior Member
 
ITD's Avatar
 
Join Date: Apr 2004
Location: Massachusetts and Moultonboro, NH
Posts: 2,388
Thanks: 358
Thanked 482 Times in 263 Posts
Default

Check the connections, make sure they are not corroded and tight. You need to put a regular charger on that battery to get it fully charged, then you can use the trickle.
ITD is online now   Reply With Quote
Sponsored Links
Old 06-06-2021, 02:37 PM   #6
Garcia
Senior Member
 
Join Date: Aug 2017
Posts: 400
Thanks: 90
Thanked 188 Times in 115 Posts
Default

I connected a battery charger and left it on all day. It showed the battery fully charged. Connections are clean and tight, the only switch I am leaving on is the automatic bilge. The jump pack if fully charged and in the boat. If its dead when I return I either have a bad battery or there is something drawing power.

Fingers crossed it starts right up when I need it!
Garcia is online now   Reply With Quote
Old 06-06-2021, 08:58 PM   #7
ApS
Senior Member
 
ApS's Avatar
 
Join Date: Jan 2005
Location: Winnipesaukee & Florida
Posts: 5,296
Thanks: 1,622
Thanked 641 Times in 454 Posts
Default

Quote:
Originally Posted by mswlogo View Post
10 min really isn’t enough, but it shouldn’t be stone dead the next time you use it. Lead Acid batteries don’t like being left discharged. I always disconnect battery for winter. “Trickle charger” may not cut it. You want a “smart charger”. It can also tell you if the battery is any good when it’s done. Chargers like these have brought batteries back that I thought were surely gone. My first battery lasted like 3 years. My 2nd battery (after buying a similar charger) lasted 14 years, and was still good when I sold the boat.

https://www.amazon.com/gp/product/B07CZG91FV
It’s also possible you have a leak in the boat. A crude old test I used to do was use a tail light bulb and put it in series with the (charged) battery connection. If it lights up, you have a significant leak.

But today I’d use an amp meter like this one. One of my favorite tools.

https://www.amazon.com/gp/product/B001TCWL1E
A check can be made without meters or bulbs. This check must be made at night, in total darkness.

Hold the removed terminal clamp against the post you just removed it from. If there's a parasitic drain, tiny sparks will jump from the post to the terminal. It must be totally dark, so cover the working area (and your head) with a thick blanket. Keep flammables well away.
ApS is offline   Reply With Quote
Old 06-07-2021, 08:53 AM   #8
mswlogo
Senior Member
 
Join Date: Jun 2014
Posts: 371
Thanks: 130
Thanked 155 Times in 92 Posts
Default

Quote:
Originally Posted by ITD View Post
Check the connections, make sure they are not corroded and tight. You need to put a regular charger on that battery to get it fully charged, then you can use the trickle.
Good point. It’s not a good idea to “trickle” charge a dead battery. Trickle is for maintaining, not charging.
mswlogo is offline   Reply With Quote
Old 06-07-2021, 08:56 AM   #9
mswlogo
Senior Member
 
Join Date: Jun 2014
Posts: 371
Thanks: 130
Thanked 155 Times in 92 Posts
Default

Quote:
Originally Posted by ApS View Post
A check can be made without meters or bulbs. This check must be made at night, in total darkness.

Hold the removed terminal clamp against the post you just removed it from. If there's a parasitic drain, tiny sparks will jump from the post to the terminal. It must be totally dark, so cover the working area (and your head) with a thick blanket. Keep flammables well away.
LOL, sometimes you can hear the tiny sparks too
mswlogo is offline   Reply With Quote
Old 06-07-2021, 05:15 PM   #10
gwhite13
Senior Member
 
Join Date: Aug 2013
Location: Hanover and Moultonborough
Posts: 78
Thanks: 7
Thanked 14 Times in 10 Posts
Default

Even Interstate batteries are now lasting 1-3 yrs. Just changed one out under warranty. Less than one yr. old.
gwhite13 is offline   Reply With Quote
Old 06-07-2021, 09:38 PM   #11
ApS
Senior Member
 
ApS's Avatar
 
Join Date: Jan 2005
Location: Winnipesaukee & Florida
Posts: 5,296
Thanks: 1,622
Thanked 641 Times in 454 Posts
Question Hearing Sparks?

Quote:
Originally Posted by mswlogo View Post
LOL, sometimes you can hear the tiny sparks too
The tiny sparks I've got experience with couldn't be heard--only seen. Sparks you can hear indicate a major drain, not an overnight loss.

Also, keep the top of your battery clean. Loss of charge can travel across dust and dirt. Keep the rag you use. Watch accumulated acid eat holes through it after a few days!
ApS is offline   Reply With Quote
Old 06-07-2021, 09:54 PM   #12
Downeast
Senior Member
 
Downeast's Avatar
 
Join Date: May 2015
Location: lakes region
Posts: 86
Thanks: 1
Thanked 26 Times in 16 Posts
Default

Quote:
Originally Posted by mswlogo View Post
Good point. It’s not a good idea to “trickle” charge a dead battery. Trickle is for maintaining, not charging.


correct.

under rating is as damaging as over rating.

charge rates at 15-25% of AH capacity is recommended. 10% is borderline. ie, 100ah , round numbers here, such as a group 31 deep cycle would rather be charged between 15-25amps than it would at 10 amps. Anything less will not only take forever, time-out a charger but will simply not be aggressive enough of a rate to prevent/break up sulfation
__________________
www.nwmarineindustries.com
@nwmarineindustries

Last edited by Downeast; 06-08-2021 at 07:44 PM.
Downeast is offline   Reply With Quote
Old 06-08-2021, 07:27 AM   #13
XCR-700
Senior Member
 
XCR-700's Avatar
 
Join Date: Sep 2008
Location: Andover, MA
Posts: 907
Thanks: 503
Thanked 326 Times in 191 Posts
Default

The answer to the original questions about how long to recharge a battery thats dead (assuming is is not more than 3 years old and/or has other problems) is that it will take hours of driving your boat to recharge it to a near full charge.

Outboard motors dont throw a lot of current, and what it generates must power all the electrical devices on the boat when its running.

AND, batteries dont charge in minutes, its hours.

The advice about a "smart charger is very good, they are much better then trickle chargers, but dont waste your money on a 1 amp or 2 amp model if you do many 10 minute runs in the boat, you will really need something more powerful.

ProMariner mages some good ones; https://www.overtons.com/promariner-...er-706694.html

Also the BatteryMINDer brand is really good and will extend the life of well used batterys better than most other brands; https://www.northerntool.com/shop/to...1886_200661886

Good luck!
XCR-700 is offline   Reply With Quote
Old 06-08-2021, 08:58 AM   #14
swnoel
Senior Member
 
Join Date: Jan 2007
Posts: 435
Thanks: 69
Thanked 155 Times in 94 Posts
Default

As some have said your alternator is not designed to charge the battery. The battery is probably fine and needs to be recharged do it with a decent charger until fully charged. If you have a automatic bilge without some sort of trickle charger hooked up it will eventually drain the battery. If you don't have power to the area where your boat is located you may want to look into a solar charger.
swnoel is online now   Reply With Quote
Old 06-08-2021, 09:23 AM   #15
Garcia
Senior Member
 
Join Date: Aug 2017
Posts: 400
Thanks: 90
Thanked 188 Times in 115 Posts
Default

Quote:
Originally Posted by swnoel View Post
As some have said your alternator is not designed to charge the battery. The battery is probably fine and needs to be recharged do it with a decent charger until fully charged. If you have a automatic bilge without some sort of trickle charger hooked up it will eventually drain the battery. If you don't have power to the area where your boat is located you may want to look into a solar charger.
Appreciate all the responses. As I said in the original post, first time I can remember a dead battery in a boat - and that goes back decades! Hopefully leaving it on the charger did the trick. I'll find out on Friday!
Garcia is online now   Reply With Quote
Old 06-09-2021, 07:24 AM   #16
BroadHopper
Senior Member
 
BroadHopper's Avatar
 
Join Date: Oct 2004
Location: Laconia NH
Posts: 5,118
Thanks: 2,678
Thanked 967 Times in 680 Posts
Default Spring launch

It's a habit of mine to check the batteries in the spring. I always find the batteries need water and a full charge. I use distilled water and fill to the rings, then charge the battery to full on a smart charger. Trouble-free for the summer!
This is when I find battery troubles such as the battery won't hold a charge, bulging battery, or corrosion around the post. The best time to take care of this is at the beginning of the season.
__________________
Someday may never be an actual day.
BroadHopper is offline   Reply With Quote
The Following User Says Thank You to BroadHopper For This Useful Post:
XCR-700 (06-09-2021)
Old 06-09-2021, 08:39 AM   #17
mswlogo
Senior Member
 
Join Date: Jun 2014
Posts: 371
Thanks: 130
Thanked 155 Times in 92 Posts
Default

Quote:
Originally Posted by ApS View Post
The tiny sparks I've got experience with couldn't be heard--only seen. Sparks you can hear indicate a major drain, not an overnight loss.

Also, keep the top of your battery clean. Loss of charge can travel across dust and dirt. Keep the rag you use. Watch accumulated acid eat holes through it after a few days!
I *could* hear sparks from 1.5V AA battery. Maybe not today though ;(

I could hear sparks low enough on car battery that the drainage is “normal”.

I could hear it better than I could see it.

But again, an amp meter is the best because a little drainage is normal.

Also you can get a little inrush, like from charging caps in a radio that can be misleading. You want to see the settled current. And a little is common depending on the setup.
mswlogo is offline   Reply With Quote
The Following User Says Thank You to mswlogo For This Useful Post:
XCR-700 (06-09-2021)
Old 06-09-2021, 08:41 AM   #18
XCR-700
Senior Member
 
XCR-700's Avatar
 
Join Date: Sep 2008
Location: Andover, MA
Posts: 907
Thanks: 503
Thanked 326 Times in 191 Posts
Default

Quote:
Originally Posted by BroadHopper View Post
It's a habit of mine to check the batteries in the spring. I always find the batteries need water and a full charge. I use distilled water and fill to the rings, then charge the battery to full on a smart charger. Trouble-free for the summer!
This is when I find battery troubles such as the battery won't hold a charge, bulging battery, or corrosion around the post. The best time to take care of this is at the beginning of the season.
OUTSTANDING advice.
XCR-700 is offline   Reply With Quote
The Following User Says Thank You to XCR-700 For This Useful Post:
BroadHopper (06-10-2021)
Old 06-09-2021, 02:12 PM   #19
Descant
Senior Member
 
Join Date: Mar 2006
Location: Merrimack and Welch Island
Posts: 2,866
Thanks: 833
Thanked 1,066 Times in 666 Posts
Default Address the cause, not the symptoms

Quote:
Originally Posted by Garcia View Post
Appreciate all the responses. As I said in the original post, first time I can remember a dead battery in a boat - and that goes back decades! Hopefully leaving it on the charger did the trick. I'll find out on Friday!
First started reading this thread today. Lots of good info about batteries and chargers but little concern about what drained the battery, since this was a first. The OP mentioned rain, but surely there have been other deluges when the bilge pump ran and the boat still started. I'm reminded of two instances with similar symptoms (drained battery) on two different boats. In one, the grand kids were playing in the cuddy and left a light on. Not noticed until days later when: no start. Simple solution: turn off the master switch when the boat was not in use. Second instance: several weeks into the season, the boat sunk at the dock. We had been using it frequently, no problems. Then stopped using it for a couple of weeks. Turns out there was a leak in the bellows through hull. The bilge pump kept up when the boat was being used and mostly wasn't noticed as water ran to the stern and was pumped when under way. Changed oil a couple of times, new bellows. No other problems. Point is, it appears to me that the OP may not have a battery problem; replacing, charging the battery etc. may simply mask symptoms of another issue.
Descant is offline   Reply With Quote
The Following 3 Users Say Thank You to Descant For This Useful Post:
ApS (06-09-2021), BroadHopper (06-13-2021), XCR-700 (06-09-2021)
Old 06-09-2021, 03:57 PM   #20
XCR-700
Senior Member
 
XCR-700's Avatar
 
Join Date: Sep 2008
Location: Andover, MA
Posts: 907
Thanks: 503
Thanked 326 Times in 191 Posts
Default

Quote:
Originally Posted by Descant View Post
First started reading this thread today. Lots of good info about batteries and chargers but little concern about what drained the battery, since this was a first. The OP mentioned rain, but surely there have been other deluges when the bilge pump ran and the boat still started. I'm reminded of two instances with similar symptoms (drained battery) on two different boats. In one, the grand kids were playing in the cuddy and left a light on. Not noticed until days later when: no start. Simple solution: turn off the master switch when the boat was not in use. Second instance: several weeks into the season, the boat sunk at the dock. We had been using it frequently, no problems. Then stopped using it for a couple of weeks. Turns out there was a leak in the bellows through hull. The bilge pump kept up when the boat was being used and mostly wasn't noticed as water ran to the stern and was pumped when under way. Changed oil a couple of times, new bellows. No other problems. Point is, it appears to me that the OP may not have a battery problem; replacing, charging the battery etc. may simply mask symptoms of another issue.
Again, outstanding advice.
XCR-700 is offline   Reply With Quote
The Following User Says Thank You to XCR-700 For This Useful Post:
BroadHopper (06-10-2021)
Old 06-12-2021, 02:54 PM   #21
Garcia
Senior Member
 
Join Date: Aug 2017
Posts: 400
Thanks: 90
Thanked 188 Times in 115 Posts
Default Problem resolved, I hope

After charging the battery fully last weekend, I arrived on Friday night and the boat started without an issue.

My guess (and hope) is that the battery was never fully charged at the start of the season and it drained during the two week rainy period it sat on the slip. While the jump pack got it started, the battery did not get fully charged until I left it on the charger overnight.
Garcia is online now   Reply With Quote
The Following User Says Thank You to Garcia For This Useful Post:
mswlogo (06-16-2021)
Reply

Bookmarks

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is On

Forum Jump


All times are GMT -4. The time now is 09:08 AM.


Powered by vBulletin® Version 3.8.11
Copyright ©2000 - 2021, vBulletin Solutions Inc.

This page was generated in 0.66494 seconds