2017 Phoenix 921PHX having cranking battery issue. (HELP)

[ewelch]

My set up is a 2017 Phoenix 921 PHX/ Mercury 250 PRO XS and 8' Power Poles, with 1 Helix 12" SI at console and 1 12" Helix DI at bow. On March 2019 I replaced the Intimidator 8a31TM cranking battery that came with my boat, with a Academy Exide 31 series battery because I had fished multipe days and forgot to plug the charger up that night and next day went to back the boat in at Chickamauga and it would not crank the motor. Exide worked great had no problems till this January, went to Dale Hollow fished for 4 days and on 3rd day was fishing in Horse Creek where we was staying it was almost dark and went to crank the boat and the Helix at the console cut off and the motor would barely turn over, so we had to use the trolling motor to get back to the dock. Pluged the 4 bank charger up and showed all 4 batteries charging, next morning when we started out to fish I had all 4 green lights on the charger. 4th day fishing battery gets week on me again, when fishing I'm not running any live well pumps, you can hear nothing running. So the Exide had a 2yr replacement and I returned it to Academy and they know longer sold them, so they give me a Optima blue top 31. It went low enough for the unit at console to cut off but the motor still cranked. charger is still showing green lights after a over night charge. So I disconnect the onboard charger for the cranking battery and plug the cranking battery up to my 12v portable charger for two days. I go fishing today and fish 8hrs and my Helix at the console cuts off, I turn it back on and turn on the volt reading that shows on the graph and it's reading 10volts when I cranked the motor the voltage went down to 7v, when I was runing back to the ramp it was showing 11v. Should it not be showing 13 to 14 volt when the boats running down the lake at 50 mph. Sorry this is so long, it's about to run me bat S#@$ crazy.

[haus9393]

So you fished multiple days in a row and never plugged your batteries in at night?

[ewelch]

No, I fished multiple days and pluged it up every night except that one night

[TYvII]

If you were fishing a while without using the big motor much the issue could just be those big graphs use a ton of juice. I had this happen to me before. That’s why I used to carry jumper cables in the boat so I could jump it off a trolling battery. I know have a jump pack that I’ll throw in the boat. I also saw drewtek is selling a cool jump starter that connects to the battery. It will jump your battery by through your phone or a push of a button on the unit.

[fishin couillon]

Showing 11v is pretty low....but mybe it wasn't showing 13-14 while running cause the voltage was to low and needs time to get to 13v....

[kry29]

Did it start normal or did it seem weak? Birds are REALLY volt sensitive. I would check the voltage at the battery, then at the fuse block in the rod box, then at the back of the graph and see how much voltage drop your getting. If your not getting a good voltage on the battery get it tested which might not be a bad idea anyway

[haus9393]

If you fished 2 full days in a row without charging your batteries while running 2 helix 12 units all day that makes sense for a dead battery. That battery will probably only run for about 14 hours before it dies. It’s simple math. That group 31 probably has about 70ah or usable power even though it’s a 100ah battery. 70ah divided by about 5 amps per hour which is me being generous on your graph power consumption. I think each helix 12 draws between 2-3amps per hour. 70/5 is 14 hours of run time.

[haus9393]

Also in the past when I’ve killed batteries on the water and jump started the motor the cranking battery is so dead that it will read about 11v even with the alternator running. It doesn’t just jump to 14 unless the battery is well charged.

[Hooked247]

Haus9393 is hitting it on the mark. Unless your running lithiums, with today's electronics your not getting two days out of any single AGM cranker. Heck not even a day and a half with "normal" fishing conditions. Any of the pro's not running lithiums are running dual 31 AGM's for a reason. I was one of those guys who scratched my head for the longest time because I had an Odyssey 31, and I thought I knew..... I had the same exact 11 volts issue on my 920 after 4 - 5 hours of fishing. I was fed up, rewired with 6 guage switched power and ground from the battery, to a dedicated fuse block, and running 10 gauge from the block to each unit, 3 12" units and a livescope box, and I see 12.8 - 13.2 all day long on the same exact batteries. My units no longer cut off or work randomly. And getting back on topic, of course I have to recharge and plug up after each outing or I would not expect to get very far from the ramp.

[ewelch]

I understand the 12" graphs pull more power. But yesterday I was running around a lot on the lake, plus the problem just started last month I've never had issue with it before.

[MichPhoenix77]

https://www.amazon.com/NorthStar-NSB.../dp/B00QJ6RUYI


I run 2 - 12” Solix, a 12” Helix and 360 and have zero issues with this battery. Not cheap but money well spent.

[haus9393]

If you mean you have been having issues with the optima for the last month then it is the optima. Optima is the worst.

[Tom Edwards]

load test the optima battery, all of them.

[Hooked247]

Optima's are not the battery to have, and the Blue top 31 only has a 155 minute reserve capacity. You want at least 200 minutes on the cranker. The NorthStar battery MichSkeeter77 mentions has a 220 minute reserve and is one incredible battery. I would load test your current batteries. I've purchased new batteries that didn't last 6 months, don't let cost fool you.

[km9e]

My set up is a 2017 Phoenix 921 PHX/ Mercury 250 PRO XS and 8' Power Poles, with 1 Helix 12" SI at console and 1 12" Helix DI at bow. On March 2019 I replaced the Intimidator 8a31TM cranking battery that came with my boat, with a Academy Exide 31 series battery because I had fished multipe days and forgot to plug the charger up that night and next day went to back the boat in at Chickamauga and it would not crank the motor. Exide worked great had no problems till this January, went to Dale Hollow fished for 4 days and on 3rd day was fishing in Horse Creek where we was staying it was almost dark and went to crank the boat and the Helix at the console cut off and the motor would barely turn over, so we had to use the trolling motor to get back to the dock. Pluged the 4 bank charger up and showed all 4 batteries charging, next morning when we started out to fish I had all 4 green lights on the charger. 4th day fishing battery gets week on me again, when fishing I'm not running any live well pumps, you can hear nothing running. So the Exide had a 2yr replacement and I returned it to Academy and they know longer sold them, so they give me a Optima blue top 31. It went low enough for the unit at console to cut off but the motor still cranked. charger is still showing green lights after a over night charge. So I disconnect the onboard charger for the cranking battery and plug the cranking battery up to my 12v portable charger for two days. I go fishing today and fish 8hrs and my Helix at the console cuts off, I turn it back on and turn on the volt reading that shows on the graph and it's reading 10volts when I cranked the motor the voltage went down to 7v, when I was runing back to the ramp it was showing 11v. Should it not be showing 13 to 14 volt when the boats running down the lake at 50 mph. Sorry this is so long, it's about to run me bat S#@$ crazy.

I run a Solix 15 & 12 and have similar issues. When I ran the Ranger Z520C, I had to put in a second starting battery in parallel. Just too much current draw with these new electronics, as others have stated. After buying the Phoenix, I didn’t want the extra weight of a 5th battery. installed the Tournament Saver Pro. It is a simple system which connects to your starting battery & your 1st trolling motor battery. There is a button at the console that activates a relay in the small unit to the trolling motor battery, and your good to go. I always carry jumper cables on the boat for the “other” guy who is dead on the water as a backup. The TSP runs $99 at TH Marine!