I have a 2003 fx140 with 240 hours. I started to notice within the last 5 hours that it isn't reaching full rpm, about 700 rpm shy of redline. I noticed this crack in the rubber and opened it up a little bit to get a good look and now it will only go 30mph, and it shoots a light mist of water out of the crack.
The first picture is looking straight down the back left corner of the main engine compartment. Click image for larger version. 

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The second shot is a close up of the rubber part that joins two metal exhaust pieces together. Click image for larger version. 

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I think it is part # 31 but im not sure.
http://www.boats.net/parts/search/Ya...201/parts.html