90 Optimax low voltage alarm when starting.

[bassfisher444]

90 HP Optimax serial# 1B803508 model# 1090D73HY
My boat had a D34M Optima battery last year when I got it, and I didn't have any trouble with it all last year but I wanted to upgrade to something with more capacity that met the requirements since the one I was using was technically undersized. I got Group 31 Commercial battery that's rated for 1000 CCA, used the marine terminals, put the motor leads on first and tightened everything down tight with lock nuts and the voltage often drops below 10 volts when cranking and I get a low voltage alarm, it dies the first few times I try to start it at the ramp then it does alright the rest of the day but I still get the low voltage beep when cranking and I can see my volt meter drop down below 10. I pulled the battery out and took it back to Advance and it tested just over 1000 CCA and over 1200 CA. My alternator is working fine showing between 13-14 volts on the gauge when running, I always have it fully charged with my on board charger before I go out, and I have a cutoff switch for all of my accessories to prevent any battery drain. I also took the battery connections apart, cleaned and tightened them at the motor and starter connections and it is still doing the same thing. What else could be the issue? It hasn't left me stranded yet, it always starts but I would like to figure out what the problem is.
https://shop.advanceautoparts.com/p/...p30/11968148-P

[EuropeanAM]

Is the ENGINE connected through a Battery Cutoff Switch?

[bassfisher444]

Is the ENGINE connected through a Battery Cutoff Switch?

No just the accessories, the cables for the engine run straight to the battery.

[JOE54]

starter may drawing too many amps/dragging

[bassfisher444]

How many amps should the starter pull?

[JOE54]

150 under load /60 no load

[EuropeanAM]

^^^^ Check this- many times the starter just needs to be rebuilt.

Another common item is "green wire disease" in the battery cables.

[bassfisher444]

Starter is pulling 150 amps when cranking.

[CatFan]

I’d put a meter on the battery terminals (not the wires, part of the battery) and measure your voltage while cranking. This will help narrow down whether you have a battery issue, or a wiring/load issue.

[bassfisher444]

The voltage is dropping to 11.2-11.5v at the battery when cranking.

[EuropeanAM]

That's not terrible. Now check at the starter solenoid (slave solenoid) and the engine block while cranking.

[bassfisher444]

Should it beep when the key is tuned to run then beep again when you turn it over to start it? Going though some of my old videos on my phone I noticed that it was doing that last year when I first got it as well, but it doesn't seem to do that all the time, or maybe it does but I don't always notice. What else would cause it do die 2-3 times when I first put it in the water? It doesn't do that the rest of the day and it has never done that at home when I run it on the muffs. The only thing I can think of is I always pump primer bulb a few times before I put the boat in the water, but I never do that while on the water, could pumping the primer bulb be giving it too much fuel causing it to die on startup the first couple times? I wouldn't think that would be an issue on a fuel injected motor but I could be wrong.

[EuropeanAM]

Test beep when you turn the key on. There are no other "intentional" horn signals sent unless a fault or fault condition is occurring. There were a few calibrations that had a strange low-voltage fault on cold starts: This engine should NOT be one of them.