So I get a call from a guy who owns a 24' center console and he's having charging issues. The boat is only three years old and the batteries are having trouble starting the motor. Like many of these small fishing boats they isolate the motor starting from house loads so they can shut down the motor and start it multiple times per day without dropping instruments, fish finders etc. to low voltage. This boat was no exception. It had two on/off switches and the owner had been using "combine" to start the motor..
So the marina diagnoses this as the need for a new alternator! "Alternators toast, you need a new one."....The alternator on a Yamaha 250HP four stroke is NOT cheap. Last night at about 8:00 I got to his boat for a second opinion. Well one battery was dead for sure but only because the marina forgot to connect the ground wire. The other one was at 12.1 volts. The ground wire was pinched under a piece of fiberglass and appeared to go to something but really it was supposed to tie to the second battery. Marina guy "assumed" the bank was connected but never tested it. Problem one solved, connect battery 2 ground wire, marina never caught it.
I then proceeded to test the batteries and they were literally toast. The boat has no shore charger or means of charging other than the engine. The batteries installed were also starting only batteries and one was being asked to do some deep cycling running radar, 10" plotter and a myriad of bait well pumps.
So I fire up the motor put my clamp meter on and the alt is putting out just 4 amps into two completely dead group 27 batteries. Here's where the marine made a mistake. The problem was not the alternator but rather HEAVILY sulfated batteries that would simply not accept any charge due to the massive sulfation on the plates.
So in went two new Sam's Club / Duracell group 27 batteries and miraculously the "dead" alternator is pumping out 26 amps at idle!!!!!
The marina's "estimate" was $1300.00 more than my entire bill and did not even include new batteries!!!! I am sure it would have once they realized the new alternator still pumped nothing into the batteries...
Batteries not accepting much current, when they should, is a sure sign they are heavily sulfated and toast...
Please always try to get a second opinion......
So the marina diagnoses this as the need for a new alternator! "Alternators toast, you need a new one."....The alternator on a Yamaha 250HP four stroke is NOT cheap. Last night at about 8:00 I got to his boat for a second opinion. Well one battery was dead for sure but only because the marina forgot to connect the ground wire. The other one was at 12.1 volts. The ground wire was pinched under a piece of fiberglass and appeared to go to something but really it was supposed to tie to the second battery. Marina guy "assumed" the bank was connected but never tested it. Problem one solved, connect battery 2 ground wire, marina never caught it.
I then proceeded to test the batteries and they were literally toast. The boat has no shore charger or means of charging other than the engine. The batteries installed were also starting only batteries and one was being asked to do some deep cycling running radar, 10" plotter and a myriad of bait well pumps.
So I fire up the motor put my clamp meter on and the alt is putting out just 4 amps into two completely dead group 27 batteries. Here's where the marine made a mistake. The problem was not the alternator but rather HEAVILY sulfated batteries that would simply not accept any charge due to the massive sulfation on the plates.
So in went two new Sam's Club / Duracell group 27 batteries and miraculously the "dead" alternator is pumping out 26 amps at idle!!!!!
The marina's "estimate" was $1300.00 more than my entire bill and did not even include new batteries!!!!
I am sure it would have once they realized the new alternator still pumped nothing into the batteries...Batteries not accepting much current, when they should, is a sure sign they are heavily sulfated and toast...
Please always try to get a second opinion......
