Charge Issue

[dljohnson69]

I recently purchased a 2006 BassTracker Pro Team.  Good shape, great rig.    After a few weeks the trolling motor peters out about an hour into use.  Checked it at the auto parts store, battery done.....replaced it.   Worked all day the first couple of times and then it got about 2-3 hours after a charge, now gets about an hour of use after an overnight charge.   My assumption is the on board charger.  It looks like it's a 8 amp 2 bank Guest charger, assuming it's around the same age as the boat but not privy to that info.   In Googling for a replacement, I don't see an 8 amp and not experienced enough to know the next closest replacement.  I've never had any issues with the outboard, charging or starting.  Can someone give me the skinny on suitable replacement in terms of performance and cost?    Does the higher the amp (I've seen 10 amp, 15, 20) just charge it faster?    I've noticed they are a bit pricier but I always have mine charge overnight at least, so if that is the case then I don't really need that and prefer something similar.  Let me know if you have any feedback or another way to test this charger...thanks. 

 

 

[slonezp]

Dual Pro or MinnKota. Higher the amps, quicker the charge, better for the battery. Also, charge after each use rather than before each use

[Way2slow]

Make sure you understand how most multi bank on board chargers are rated.   You have to look at the amp rating per bank, many give the total capacity.  Meaning that a two bank, eight amp charger is only four amps per bank.  That means it would take it well over 12 hours to charge a 50% discharged, 100Ah battery because as a battery starts receiving a charge, the charger starts lowering the charge rate.  You should be looking at a charger rated at 10-15 amps per bank if you want to properly charge your battery.

 

 

[Maggiesmaster]

On 6/7/2017 at 6:33 AM, Way2slow said:

Make sure you understand how most multi bank on board chargers are rated.   You have to look at the amp rating per bank, many give the total capacity.  Meaning that a two bank, eight amp charger is only four amps per bank.  That means it would take it well over 12 hours to charge a 50% discharged, 100Ah battery because as a battery starts receiving a charge, the charger starts lowering the charge rate.  You should be looking at a charger rated at 10-15 amps per bank if you want to properly charge your battery.

 

 

Before you get a new charger, pick up a good quality voltmeter ($30-$50) and check the trolling motor voltage when it's charging. It should read 13-14 volts. If it does, the charger's ok & you have other problems.  If not, it needs replacing.

Most modern onboard chargers are configured to send the total output to the uncharged battery.  For example, a modern two bank eight amp charger would charge each battery at 4 amps until one is fully charged, then all 8 amps would be directed to the uncharged battery. Starter batteries are recharged by the outboard, and generally don't need much recharging by the onboard charger. The the trolling motor battery should get 8 amps, which should be sufficient. Of course, as in anything, the larger the better.

[WIGuide]

If it does turn out that it's your charger, I'd look into Dual Pro. My dad's is 18 years old and has never had an issue. I'm not sure on the age of mine as it wasn't original equipment on my boat, but I purchased it used as the original owner added a battery so they moved to a 4 bank charger instead of a 3, but mine has been in 2 of my boats and is at least 10 years old. I've never had an issue either. 

[Way2slow]

I would suggest someone read up on charger technology, I think they have a whole lot of miss information

[Maggiesmaster]

5 hours ago, Way2slow said:

I would suggest someone read up on charger technology, I think they have a whole lot of miss information

Is this not how most modern onboard chargers work? My BassPro model is about 4 yrs. old & this is what the owner's manual says. Also, my voltmeter shows a charge of around 13.6 volts at maintenance charge. 

[Way2slow]

There are only a couple chargers that use that technology.  Pro Mariner uses it and since they make the BPS brand, it's also in the BPS chargers.  However, it does not work as you described.  I think you will find your eight amps charger, generally charges at full power (Bulk rate), four amps per bank into each battery until they reach 80% charge, then the charger starts reducing the current (Absorption rate) until the battery reaches charge, plus and additional amount for approximately 20 minutes of over charge.  This is basically an equalization charge that is required for the battery to be fully charged.  Then the charger goes into the Maintenance Mode, which is approximately 13.2V for flooded cells and 13.4-13.6 for AGM.  Once a cell reaches approximately 90% charge, the charger will start shifting any available excess current from that bank to another bank if that battery is still below 80%.   So, if you connected a battery discharged below 80% to one bank and fully charged battery to the other bank, then it would charge the discharged battery at eight amps until it reaches 80% charge. 

There is no reasonable sized charger that should charge any battery at full rate once the battery has reached 80% charge.  Doing this would cause the battery to start over heating and damage the battery. 

Also, to properly charge a battery, the charger should be approximately 10% the batteries capacity, so if you are charging anything much larger than lawn and garden battery four amps is too small.  Typical group 27 batteries are over 100Ah, and group 29's over 120Ah so you should use a 10-15 amps per bank to charge them.

which means they should be charged with a 10-15 amp charger 

 

As for not charging the cranking battery, that's wrong.  Modern motors with 60Amp charging systems have helped but generally speaking, unless you are doing more running than fishing, the power your electronics and pumps are pulling is more than the motors charging system has put back into the battery by the end of a full days fishing.  Several studies have been done on tournament fishermen and their cranking batteries were only at 80% charge level at weigh-in.

[PECo]

46 minutes ago, Way2slow said:

As for not charging the cranking battery, that's wrong.  Modern motors with 60Amp charging systems have helped but generally speaking, unless you are doing more running than fishing, the power your electronics and pumps are pulling is more than the motors charging system has put back into the battery by the end of a full days fishing.  Several studies have been done on tournament fishermen and their cranking batteries were only at 80% charge level at weigh-in.

 

I agree with this. Get a charger that has enough banks to also charge your cranking battery. If you use your electronics AND your pumps (i.e., livewell or bilge), it puts a lot of demand on the cranking battery.