When I start my DF140 right after I launch the boat (starting it for the first time that day), I can hear what sounds like valves rattling for a couple of seconds. I took it to the dealer to have the valve clearance checked, but he said that the valves don't need to be checked until there is over 400 hours on the motor. I didn't get to talk to the tech when I picked the boat up, and on the phone he mentioned it was normal! Well, the engine never did this before, so how can it be normal now??? I have at least 200 hours on the engine with no problems...can anyone give me any hints to as what this noise could be??<br /><br />Thanks,<br />H Ahart