Warning horn beeps while cranking

[jeffadams]

I have a 2010, 175 HP regular optimax, serial number 1B789623. When i turn the ignition on, the horn beeps one time, like it should. When I crank the engine, the horn quickly beeps again while the starter is turning the engine over. When the engine starts, it runs fine and no horn sounds occur.

This all happens only once and it occurs when the engine has not been run for a day or two. After the engine has run a while, I'll get the regular one beep when the ignition is energized, but no horn while the starter is turning the engine over. Why would the horn go off while the starter is turning the engine over, and why does it only occur after the engine has not been run for a day or two? Is there some kind of low voltage situation that only occurs after the engine has set a while? What could I check to verify?

The battery is 1000 cranking amps and I've swapped batteries thinking that that was the problem, but that was not the problem.

[EuropeanAM]

Really need a battery that is 950 or higher COLD Cranking Amps (CCA) for a fishing application. If yours is 1000 CA, that would be about the absolute bare minimum for your engine (alone), with no boat accessories.

What you have described has all the earmarks of a "low voltage" condition on initial startup. Strongly suggest an upgrade to higher capacity battery, with clean/clamp style terminals.

For more info, see the FAQ Section for "Batteries that Meet the Requirements".

[jeffadams]

Both batteries I tried were 1000 CCA, so respectfully, I believe the batteries are sufficient. Does the optimax warning system have a warning horn that indicates low voltage?

[lpugh]

Believing is not good enough, test them on a quality battery tester to be positive, 950 cca and at least 175 minutes reserve

[leonreno]

Do you charge your batteries between uses? If batteries are fine check the voltage with VOM before starting, will give you some indication of wether it’s low voltage.

[JOE54]

^^^^^^ +1 to both

[SilverFox579]

Jeff you're using cold cranking and cranking amps interchangeably and they are not the same.

MCA (marine cranking amps) and CA (cranking amps) are the same capacity specification at 32° but neither are the same as CCA (cold cranking amps) which is capacity at 0°. A typical battery with 800CCA will have 1000MCA/CA, and regardless of how capacity is stated, that is the absolute minimum for an Optimax, engine only, and no accessories.

There is an excellent battery topic in the FAQ that covers which batteries are best for an Optimax.

BATTERIES THAT MEET THE REQUIREMENTS