Severe electrical issues Please Help!

[Dam0007]

I definitely wouldn’t like the alternator results at all. Possibly bad diodes? A northstar 31 agm should be able to handle 8 hours of fishing no problem with 2 9s and a 12. A northstar has 220 RC Minutes at 25 amps. You are probably consuming 8 amps with those graphs which should give you about 600 min or 10 hours of use. 12 gauge wire is still pretty small but it should work, I’d recommend 10 gauge at a minimum. What I learned is that once an alternator goes bad the battery dies extremely quick when running the engine. Try fishing without running your engine or just power up all the graphs in the driveway all day long and consistently measure voltage. You said it reads 12.8 v after a full charge. You should be able to let the graphs run all day long and see the voltage drop by the hour but it should drop gradually. After 10 hours if you see something like 12.2 volts then I would say the battery is ok. If your trolling motor batteries are fine than the charger isn’t to blame. You have been running the top of the line agm battery as well so it’s hard to believe you have had this many bad batteries. This guy had similar results with his alternator amperage. http://www.bbcboards.net/showthread.php?t=23017

dude is almost verbatim my situation except my voltage spikes. My shop said they got the alt to put out 50amps. Idk, when I tested it with merc on phone I got 19.1 at 2k. Vessel view is right on the motor and you gotta be wot to get over 13V. Let’s see what this switch elimination does. Fingers crossed.

[Dam0007]

I had Mr. Dam007 eliminate the switch completely and xfer the hot wires to the battery. The talons went to the graph switch. Not seeing much (if any really) parasitic draw aside from .02 or so with graph switch on. Somebody doesn't carry a spare key in his boat so we couldn't verify the alternator output yet. His wife is taking him fishing tomorrow so after she out fishes him, he'll let you know how it goes.

I went home and got my key lmao didn’t have my ears.

[haus9393]

dude is almost verbatim my situation except my voltage spikes. My shop said they got the alt to put out 50amps. Idk, when I tested it with merc on phone I got 19.1 at 2k. Vessel view is right on the motor and you gotta be wot to get over 13V. Let’s see what this switch elimination does. Fingers crossed.

I was googling the output amperage of the alternator and came across that thread just minutes before posting it here. I read that it’s supposed to be 50 amps and I wanted to see if it was sufficient enough to charge 2 large agm batteries like I’m using for my cranking setup. I have a northstar 31 agm that would die after 8 hours with my current gps setup in my signature. This year I added another Duracell group 31 agm in parallel and it’s been awesome having that much power. I can fish all day (12 hours so far) and still have 50-60% of battery left. My batteries appear to be charging correctly via the alternator and see 14 volts sometimes and always over 13 when running but I wanted to see how close to the limit I actually was if there even is a limit. Anyway that’s besides the point but I had read that entire thread from 2010 how the guy thought his alternator was bad and they kept saying it was good. Then I come on here and read your post and said holy crap I literally just read a similar situation a few minutes ago. Definetly hook the motor leads directly to the battery first like you said you did. Then go from there. But like I said before run your graphs all day in the driveway or garage and just see how the battery holds up. I don’t trust many mechanics. Don knows what he’s doing so is listen to him but in my days in northern ny most of them have no idea what they are doing. I had a cracked exhaust housing causing my boat to run about 20 mph and feel like only 1 cylinder was working and my mechanic said he fixed it by replacing spark plugs and a loose battery connection. My connection wasn’t loose and my plugs were fine but oh well they could have probably used a new set. Then they said they water tested it and it ran wide open. I got the boat back the next day and I couldn’t even get on plane. They even charged me 180 bucks for the water testing on an engine under factory warranty when it obviously never happened or they would have found that the motor still didn’t run right. Plus it’s pretty hard to just dump a Phoenix bass boat in the water and run it wide open first time behind the wheel. That was the last time my engine went to them. Anyway point I’m trying to make is just because they work at a dealership doesn’t mean they know what they are doing. And I’ve got a whole plethora of stories on top of that one.

[Dam0007]

Todays results with no battery switch. For some reason vessel view wasn’t working got it to work on my girls phone, idk Bluetooth wasn’t working so going by gauge and graph.

Started her up 12.8V at the graph
idled for a bit held 12.8 trimmed down dropped to 12.1 then climbed back to 12.8..

wot 13.3 came off plane 12.8

fished for a half hour dropped 11.7

wot 13.3 at graph, see gauge pic below

number cycles like this throughout the day

got home checked V at battery, 12.57v everything off

so today
- graphs never dimmed starting motor
- graphs never went below 12.1 while motor running
- graphs never dimmed while using Talons andbtheyre on same switch
- had enough power in battery to start motor every time (7hrs on the water)

[Dam0007]

I would recommend that you remove the Engine Cable from the Battery Switch, and connect it DIRECTLY to the Cranking Battery. Engine cable FIRST, remaining lugs Largest to Smallest and finish off with a Nut or Stainless Locknut.

I know- you want a battery switch. Maybe later... let's rule it out, and for GOOD REASON.

If you lose connection to the battery while the engine is running (or have intermittent loss of connection) the Alternator goes to FULL OUTPUT, and voltage will climb FAR HIGHER than intended.

While most will check cables and connections- SWITCHES are often the weakest link in the system. Especially since they really can't carry anywhere near the capacity of the battery itself.

Be sure to report back...

forgot to reply to you ^^

[Savage]

Todays results with no battery switch. For some reason vessel view wasn’t working got it to work on my girls phone, idk Bluetooth wasn’t working so going by gauge and graph.

Started her up 12.8V at the graph
idled for a bit held 12.8 trimmed down dropped to 12.1 then climbed back to 12.8..

wot 13.3 came off plane 12.8

fished for a half hour dropped 11.7

wot 13.3 at graph, see gauge pic below

number cycles like this throughout the day

got home checked V at battery, 12.57v everything off

so today
- graphs never dimmed starting motor
- graphs never went below 12.1 while motor running
- graphs never dimmed while using Talons andbtheyre on same switch
- had enough power in battery to start motor every time (7hrs on the water)

Battery should not read 11.7 volts @ 1/2 hour into a outing......Battery.

[Dam0007]

Battery should not read 11.7 volts @ 1/2 hour into a outing......Battery.

[haus9393]

Graph readings on voltage are terrible. Yesterday I read 11.1 on by Lowrance unit and 12.4 at the battery with a meter. But it’s a good guide line to use it. Usually once I start seeing my graphs get into the low 10v range it means I’m about to start having some problems on the water. 12.57 volts is very good after a 7 hour trip that means you battery was somewhat only 20% drained.

[SilverFox579]

13.3v @ WOT is not good either.

[Dam0007]

Graph readings on voltage are terrible. Yesterday I read 11.1 on by Lowrance unit and 12.4 at the battery with a meter. But it’s a good guide line to use it. Usually once I start seeing my graphs get into the low 10v range it means I’m about to start having some problems on the water. 12.57 volts is very good after a 7 hour trip that means you battery was somewhat only 20% drained.

Charged battery last night, let sit over night to settle. Just checked With a multi meter, 12.88v

[Savage]

Load test required now......past load test are meaningless.

[EuropeanAM]

Roger that. Be sure to report back.

[Dam0007]

Roger that. Be sure to report back.

Got a toaster from a co worker. On call this week for work and don’t keep my boat at my house so hopefully this weekend if not Monday I’ll do the test. Everything ran great last weekend as I had an away tourney. Tops 3 hours each night for the charger to top off the battery. I believe the switch was the root of all the issues. I’ll still do this test tho as I have yet to see 14V

[Dam0007]

Roger that. Be sure to report back.

Finally able to do it. Here’s the results

[Dam0007]

Results^

Load test required now......past load test are meaningless.

[Savage]

Results^

I wouldn't trust the results from that unit. Looks like it's just barely in the green.My local battery shop uses a large, high quality tester. The results are always very accurate.

[Dam0007]

I wouldn't trust the results from that unit. Looks like it's just barely in the green.My local battery shop uses a large, high quality tester. The results are always very accurate.

Was on the money with the multimeter

[Savage]

Multimeter can't test a batteries condition.
Need a large amp load also.

[CatFan]

I wouldn't trust the results from that unit. Looks like it's just barely in the green.My local battery shop uses a large, high quality tester. The results are always very accurate.

It’s above green for just a battery. The last two ranges are for testing the charging system.

[Dam0007]

It’s above green for just a battery. The last two ranges are for testing the charging system.

Top pic was just the tester connected bottom pic is the tester at about 12 seconds when it stopped moving