[C320-list] Battery Woes

[Jack Brennan]

Hi Dean:

If it is your system, it is in the ground cable. Make sure you didn’t forget to hook up one of the ground cables and that all of them are securely tightened. 

In addition, there is a ground buss behind the circuit breaker panel. (Black wires) Poke around there with the 110 volt off, for obvious reasons, and make sure the large cable that runs from the buss back to the batteries is securely tightened.

You could charge the batteries for several hours with an auto store charger (only while you’re there and watching) and your boat electrics turned off. Then put a load on the batteries with a 12-volt fan or something similar connected directly to the batteries, not through the boat system.

 If the voltage drops to 11 or so, it’s the batteries. If the batteries keep their charge, it’s the ground in your boat system.

My 320 was a repo that had been sabotaged somewhere along the way. One of the tricks was loosening the main ground cable at the buss.  I went on a short trip, and all of the electrical went out, with the system showing 11 volts or so. (The diesel and start battery were wired separately and worked fine.)

I accidentally found the loose screw, tightened it and charged the batteries. Everything was fine after that.

Jack Brennan
Sonas, 1998 Catalina 320
Tierra Verde, Fl.






Sent from Mail for Windows 10

From: Dean Vermeire
Sent: Tuesday, June 16, 2020 10:44 AM
To: C320-List at Catalina320.com
Subject: [C320-list] Battery Woes

Ahoy,

I recently had two new batteries installed.  I will say up front that 
they are not the greatest batteries or brand (Continental 
maintenance-free 4Ds), but there are not as many choices here in 
Kansas.  I also mostly daysail, and, if I do stay on the boat overnight, 
I stay in the marina.  So, I basically need to start the engine and be 
able to run the bilge pump, refrigerator, stereo, and instruments.

The first time I went out to the boat after installing the batteries 
(about 4 days), the engine would not turn over.  I shut everything off 
to let the batteries charge as much as possible for about 15 minutes.  
When I tried again, I was able to start the engine.  I went sailing and 
left the engine running the whole time.

Two days later, I went back out to the boat and took along a volt meter 
and a battery tester.  With the charger on, I was seeing about 13.4 
volts to the terminals.  I turned off the charger and waited 30 
minutes.  When I hooked up the tester, it showed both batteries as bad 
(less than 40% of the capacity).  I tried to start the engine, but it 
would not turn over.  The voltage of both batteries then showed around 
11 volts.

So, in all likelihood I got two bad batteries.  But, what are the chances?

My real question to all of you battery wizards out there is what in my 
wiring could kill two batteries?  I get the idea that something could 
run them down, but kill them?

Our boat is #847, a 2001, with the original 2-battery configuration.  
The batteries are dual-purpose, rated for 1200 CCA.  It was about 80 
degrees when I tested.  The boat was out of the water for 18 months 
before replacing the batteries.

Thoughts?

Thanks,

Dean Vermeire

Moonstruck II (#847)