Lower Exhaust System

The lower exhaust system is in!

Center cockpit designed sailboats with auxiliary propulsion engines amidships tend to share a common design constraint. That is, how to lead mechanical bits aft without interfering with the aft cabin living spaces. Example bits are the engine exhaust and rudder steering.

Waterlift muffler with input hose from the engine room

Here I have chosen to run the engine exhaust under the floor. The cramped spaces coupled with the inflexibility of rubber exhaust hose meant that I had to put in a few elbow joints. A few more than I would prefer as the more joints, the greater the chance of leakage. But, it is what it is.

The vertical piece of hose leading up from the waterlift muffler, clears the prop shaft and coupler, but it is still a bit too close for comfort. We don’t want the hose chafing on a spinning prop shaft. I need to devise something to tie it out of the way for an extra inch or two clearance.

Vertical rise of exhaust up the the gooseneck (not pictured)

The exhaust hose rises up to join with the gooseneck and will ultimately exit the stern.

With the hose fitted I can now frame in the remaining cabinetry and floor pedestals for the aft-head.

5 comments for “Lower Exhaust System

  1. January 27, 2013 at 3:00 pm

    I read to many Blogs to know if you are aware of this zip tie holder or not.


    My thought was to hold the exhaust hose away from the shaft.

    The other thing is that I see you found the hose clamp end covers.
    I think they are one of the best thing I have bought for the boat. :))

    Bill Kelleher

  2. January 27, 2013 at 6:56 pm

    Thanks for the tip Bill. Yeah, I have a WeldMount kit and some bits. Not sure if I would use it for the exhaust hose. But I am still thinking on it.

  3. January 27, 2013 at 8:55 pm

    How about, get rid of the hose and form a fiberglass tube up past the shaft that is wider and flatter at the point nearest the shaft. You could make the inner mold from foam scraps and then burn it out with a blow torch after the fiberglass has hardened up. If you made it to follow the shape of the hull,you could tab or bolt it to the side.

  4. January 28, 2013 at 1:44 pm

    Thanks Colin. Yeah, thats an idea. I would need high temp fire resistant resin, but it could be done. I got some time to think on this one.

  5. January 28, 2013 at 11:24 pm

    You could also form it around a thin layer of SS sheet metal if you know the way of the tin knocker!

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