'82 H30 exhaust in cockpit

[malyea]

Due to the near co-location - on the port aft stern under section - of the diesel exhaust thru-hull and the starboard scupper drain thru-hull....engine exhaust will seep up thru the cockpit drain hose into the cockpit and will discolor/deposit onto the white fiberglass about ankle high in the aft area of the cockpit.....

Engines smokes very little so it takes a while but would like to fix a 'flapper' over the scupper drain thru-hull that would block inflow of exhaust but allow outflow of draining water....

Ideas?

 

[Jimmy Jenkins]

Sounds like an "S" shaped trap(like under your kitchen sink at home) mounted under deck would do it. PVC or rubber.
Jimmy

 

[Dalliance]

Interesting. Same set up on Dalliance, but I have never observed any exhaust or soot in the cockpit. I get soot on the transom though, and oddly, more to the starboard side away from the port side exhaust discharge. Your drain hoses cross to the opposite side like mine too. So I don't know... Could it just be dirt? Do you smell exhaust in the cockpit while motoring?

Either way, I think my solution would be a sponge and some boat soap now and then rather than modifying the scupper and potentially creating new unforeseen problems.

Scupper flaps work on a vertical transom, closing by gravity, but will just hang open if installed in a horizontal position on the aft hull. Plus it would drag below the waterline on starboard tack. An S-trap could fill with dirt and debris that settles in the trap and water in the trap could freeze and rupture in cold weather.