Corsa Exhaust question...

[gregtay]

Hi guys. I purchased a new boat and it came with the Corsa Quick and Quiet side exhaust and i am trying to figure out how it works. I understand the basics and when the switch is off the exhaust is unmuffled (loud!) and exits out the side ports. What i can't figure out it how it works when the switch is "off"... the exhaust sound like it is still coming out the side exhaust ports, it is just muffled and quiet (sounds very nice!). When i look in the engine compartment here is what i see.... the exhaust leaves the headers to the "y" where the switch solinoids are... one side of the "Y" leads out the sides of the boat where it exits as expected... the other side of the "Y" seems to lead down to the outdrive as it if were a through prop exhaust (which i think Corsa would call "Captains Call" if that were my setup) ... but when i look at the outdrive it is missing an exhaust bellows (just nothing there) and I never have any exhaust bubble out the back of the boat (or for the prop.)

So everything is working fine... but i am an engineer and i have to know how things work.. Where does the exhaust get routed when my switch is in the off position?

Details: 2007 Crownline 240LS w/ Merc 5.7 350MAG B3 (and this is my first Merc (been a Volvo lover... so my "i don't have an exhaust bellows" is sort of a guess... but it looks similar to the volvo and there is a big cutout for the bellows... just nothing there.)

(Oh, and Don, welcome to Washington.. next time i am out your way i need to buy you a beer for all the help you have provided on my boats!)

thx!
-Greg

 

[Zackman]

Re: Corsa Exhaust question...

Greg, I'm not sure exactly what you have, but here's some additional information http://www.corsaperf.com/mcompare.htm

I have the Captains Call on a 99 350 MAG and B3 combo, which exits thru the transom when engaged. When disengaged, it exits thru the Y pipe and out thru the gimbal housing near the bottom. This is right below the bellows for the driveshaft. On mine, there is a bellows that is connected to gimbal housing but not the drive. The bellows aligns with an identical port on the gear housing and there is a passage inside the gear housing leading to the props. I think once underway, all the exhaust is supposed to go thru the props, which is helped by the flow of water behind the props.