Low System Voltage warning

[dennis41]

This is regarding my 2016 Cutwater 30 CB. So.......upon starting the engine for the first time after changing oil,fluids & filters, I got the dreaded "Low System voltage" message. Never happened before. The little battery symbol on the Garmin was also glowing red. Not knowing what to do, I simply clicked the "OK" button & the message went away & stayed away all the way to Blakely Hbr. It reappeared however, the next day upon starting. Clicked OK & went home.
House batteries are starting their 3rd year & thruster battery is new (all Universal). Engine battery is a Northstar & is going on its 4th year. Can't believe it's a battery issue. Our use of house batteries is very minimal (former sailboat habits).That leaves the alternator as prime suspect. How to check alternator output with my multimeter? Suggestions for a simple fix??
Discovered the Northstar company went away. A good replacement would be the Odyssey G31 Extreme, a powerful battery. But I think my Northstar still has lots of life left in it.

 

[scross]

The NorthStar brand is gone since acquired by Odyssey. But you can get the same battery at BatteriesPlus called the X2Power AGM. Bought the Group 31T version on sale for under $400 each.

https://www.batteriesplus.com/search?ca ... 20agm%2031

Needed a terminal adapter for my existing battery cables though. If you don’t want to use a terminal adapter for $60 more you can get the RV/marine terminal version.
Using as both engine and thruster batteries. Can’t beat 1150 CCA.

 

[watson1987]

When batteries are connected in parallel but with different voltages, the higher voltage battery will dump current/charge to the lower voltage battery to equalize the voltage in the system.

I had the same alarm go off in my boat when one battery was bad in the system, it would also happen after starting, or sometimes after briefly using the thrusters after startup. I suspect it was the bad battery would go from 100% after being on shore power to 'zero' and briefly the alternator was not able to keep up the demand, meaning the bad battery will surge the good ones in the system while trying to equalize. Remember that when starting the engine, the alternator will open up all the ACRs.

I haven't heard one good thing about the Universal Power Group batteries that came with the boat, except them being cheap. Is that what you meant by the batteries being Universal?

 

[dbsea]

I have a 2016 C30CB and I had the same issue. This is a result of the UBG batteries not being the appropriate CCA (cold cranking amps) for the engine. The UBG batteries are a deep cycle and have a CCA of 550. The Volvo recommendation is 950CCA at minimum, so way undersized. I replaced my start and thruster both with the Optima Group 31 Blue Top, got them at fisheries and I have not seen the issue ever again. Another thing to check is if anything is leeching your engine battery that's on your engine fuse block if what I described above doesn't sound like it matches your issue.

 

[dennis41]

SCROSS -Thanks for the battery alternative. Better price than Fisheries. Will disconnect the engine battery & load test it, although I feel it is good. A real pain, but will also individually test each house battery also. And yes, the UPG batteries are cheap - for a reason.

 

[dennis41]

dbsea - Thanks for the clue on the Optima blue top batteries. I will check them out.

 

[piglet 2013]

One other thing to look at is on the Volvo engine monitor look at the engine voltage to see when it comes up to around 14 volts after starting that should give you an idea of alternator output
Darin

 

[dennis41]

Thanks for that reminder. Will pay attention on next startup.

 

[Cutwater28GG]

i just swapped out my batteries again.

While they may not be the best AGM's for CCA I went with the universal AGM's. They are almost half the price of the northstar and lifelines. These start my volvo 260 D4 no problem.

best prices I found were home depot. https://www.homedepot.com/p/UPG-12-Volt ... /203770533

 

[DesignDay]

The NorthStar brand is gone since acquired by Odyssey. But you can get the same battery at BatteriesPlus called the X2Power AGM. Bought the Group 31T version on sale for under $400 each.

https://www.batteriesplus.com/search?ca ... 20agm%2031

Needed a terminal adapter for my existing battery cables though. If you don’t want to use a terminal adapter for $60 more you can get the RV/marine terminal version.
Using as both engine and thruster batteries. Can’t beat 1150 CCA.

The 31M verson of the X2Power lists the terminals as DT, SAE/M8 Stud, SAE/M8 Threaded Post, WNT. Are you saying that this would not require any sort of adapter for the way the batteries come from the factory? I am slightly concerned that the post will get in the way of all the leads on each battery.

https://bpb001produe1cdne.azureedge.net ... 3747_5.jpg

 

[dennis41]

Just to put this thread to rest, my problem, sadly, turned out to be the alternator. Bobby, from PPG, replaced the alternator. He had to do a lot of boat yoga to get to it. He is my new hero. Very difficult job.