Starter issues

[Gvellia]

I have a 2021 Cutwater 30CB. I keep the boat at a slip with shore power. The last 2 times we went out for a little cruise then spent time on a mooring with the large refrigerator running and the radio on for about 2 hours. Went to start the boat and it would not turn over, had to use the parallel switch to start. I am new to this boat and it’s systems, would appreciate any input. Thanks in advance.

 

[knotflying]

The engine battery should be designated for the engine only. Check to make sure this is the case on your boat. Sometimes things are not wired as they should be and something that is connected to the engine battery may be causing the drain. If that checks out, make sure all you battery connections for the engine are clean and making good contact. If all that checks out, I would then make sure the battery is fully charged and has rested for 30 minutes or longer and then do a load test with your own load tester or take the battery out and have it tested at an auto parts store.

 

[BB marine]

Engine battery ? What battery is installed? What is the Cranking amp capacity? The D6 requires a minimum of 750CCA and 88Ah @ 41F or higher, 1150CCA and 120Ah @ 23F or higher. This is not Marine MCCA. MCCA 975 = 750 CCA, 1494 MCCA= 1150 CCA. Theses are minimum ratings. A battery that is at 90% charge that is rated at 750 CCA will not start a D6 engine. Check to confirm your batteries are above the minimum requirement and are fully charged. I personally like to have a battery rated at a minimum of 20% above minimum CCA for a start battery.

 

[Gvellia]

Thanks for the reply’s, very good info to put to use.

 

[davidr]

We had similar start issues on our 2017 30CB. This winter had the mechanics dig into the issue. The factory spec battery really struggles so we had a second engine start battery installed in parallel. Problem solved! Mechanic also thought the factory wiring from battery ti starter was sized too small.

 

[Cutwater28GG]

It’s also possible your battery is just old and needs to be replaced. As the universals (typical factory option) don’t have huge CCA as they age they struggle to start once they have been left to sit for a while without being charged. (Per Brian’s note)

Check the connections to make sure they are not corroded.
do a load test
Or bite the bullet and just install a new one as it’s 3 years old.