Good to know Sir. If the boat is out of the water I'd recommend looking at the intake grates in the bottom to ensure they are not cracked/broken. Not a show stopper by any means but if they are cracked or broken then it would be wise to look at replacing them down the road. Lift the jet buckets (throttle up/throttle down) and feel for sticking or hesitation. Also if the boat is out of the water, lift the buckets (either by hand or have someone push the throttle forward) and take a good look at the impeller blades. Pay close attention to nicks, dings and or rounded edges. 300 hours on a 2015 I dont believe is a bad or high ratio of hours at all but it clearly indicates that boat has been utilized a lot.
Open the aft Clean Out Plug cover and check out hte clean out plugs as well. Ensure they go in and out easily. If I'm not mistaken this boat (2015) should have the twist to lock in place type clean out plugs. Check down in the holes on both once you get a chance to pop them out and feel around for any thing down in there. Better to check/ get familiar "out of the water so you can see from the back sides with the buckets raised as well but you can pop them out with the boat in the water as well. Great addition by Yamaha for that amazing instance when you suck up a rope (and you will eventually suck up a rope) or ingest a piece of wood or other garbage that impedes your impeller rotation. Make it a habit, should you take this boat home, to pop those plugs out once you get out of the water and do not lock them back in until you get back in the water. Not a good idea for the clean out plugs to stay locked in all the time due to the fact they can swell and get lodged in the clean out ports. Hopefully your seller has been consistent with removals. Not a big deal once again, but once they get stuck in there, they are a pain to get out.
Once out on the water run it through its paces. Ensure that once the boat is started that water is coming out of the two small ports on the right aft side of the boat. In general, if your boats not peeing, there is an issue that needs to be resolved. Either the clean out plugs are not installed correctly (or at all) or there is an obstruction in one of the lines. One other thing to be aware of, once you turn on the motors, this boat is moving forward. Neutral is not Neutral in the sense you may know it to be now. The buckets can be adjusted to somewhat counter effect this forward motion, but I don't think it has ever been completely resolved. Its just the nature of the jet boat as I understand it.
I'd recommend ensuring that all of your switches (mainly the fan and bilge pump) kick on when you hit the switches. I picked my boat up from a dealership and it had been sitting in the water for three days getting rained on HEAVILY. The bilge never kicked on and my ski locker was close to being half full of water and there was a hefty amount of water in the eng compartment as well. Make sure the bilge works!
Of course you are going to look in the engine comp so as always, look for the obvious. Oil leaks, how clean it is etc.
Once out on the water, get a good feel for the steering at speed, left and right turns, and ensure you dont feel any sticking or hesitation as well. Then, slow speed steering... If this is your first jet, you're in for some adjustment time because slow speed steering on these things is a real hoot!
I'm not well acquainted with the 2015 electronics package so I will allow the other members to chime in on that aspect. All in all if you have been around boats you will be good to go. We thrive on pictures as well so once you get that beast home share share share.
