1991 ski nautique : start only with booster pack

[Yvan52]

Like i said in the title , boat start only with a booster pack or a little bit of time with charger.
once the motor running, everything seems fine : battery between 13-14Volts then , when
i turn off the switch , turn it on it wont start and i have about 11volts on my gauge and 12.50Volts on
battery ?!?!? I have seen similar problems and it was starter relay ( at the back of the motor )
Any idea ???
Yvan

[gary s]

Possible bad battery could have condition known as surface charge. Make sure it’s charged and have a load test done. If it passes that test then suspect battery connections and or cables. Also could be starter drawing to many amps but start at the basics first and have a load test

[Yvan52]

Well i brought my battery for a check-up ( load test ) and ....right on !!!
battery is dead, even if i have 12.50v on my multimeter. I learned
something today ! Thank you Gary S !