90 seadoo gt help please

[maxfam09]

i have a 1990 seadoo gt that will run in the driveway all day.it will fire rite up when i launch it and will run near perfect while im on my initial ride but when i come back to the dock to take a break or change riders it does not want to start back up.usually takes about 20 minutes and will only start with full throttle and usually ends up over heating the starter or killing the battery.i dont think that this is a serious problem as when i am riding it it runs very well.thanks in advance for any help.