The other day a yamaha 90 Hp 2 stroke passed me and it seemed very quite compared to my 60 Hp yamaha 2 stroke of same style (year 2005, TLRD family). Can I do something to channel my exhaust completely out of the propeller? I took off the lower unit and there is no sealed tube coming from the power head down to the lower unit. The exhaust just comes down from the engine through the midsection and out the lower unit, but there is no specific tube routing the exhaust. Should it be this way? I remember on my Johnson that there was some sort of tube/channeling mechanism for the exhaust.