Please, I have a problem which I do not manage to solve.<br />My engine is a Mercury 90 HP fourstrokes (2004).<br />When the engine turns at neutral, idle speed, we can hear an unpleasant whistle.<br />This whistle becomes stronger if I accelerate with the accelerator with hand.<br />The noise is not more for if I raise the cap of the engine.<br />However, the noise stops immediately if I engage FORWARD!!!!!<br />The dealer had replaced the gear case without any result.<br />Now he says to me that this noise is normal!!! <br />I am desperate because I like my engine (I have 3 mercury before) but I think that the dealers are not very qualified.<br />Please help me.