My boat is a 2008 Hydra Sport with 2 Yamaha 250's . One has started making a noise like a loose alternator belt under the hood of a car . One dealer says I need the belts checked and possibly replaced . Another tells me it is normal and nothing to worry about . They say it is an engine bushing near the water pump and can wait until fall for lubrication . Does anyone know anything about this ? The motors are under 700 hours . Thanks !