Bilge blower piping

[ripvan1]

I'm installing bilge blower/sucker which has 3" extractor pipe. Is it feasible to reduce this down to 3/4" as this is the only spare fitting in situ in the transom.
I'm trying to avoid drilling larger hole in transom - - - but if needs must.

 

[sarabande]

3/4 would need a much higher power motor to shift the same amount of air.

I wonder if the transom is the best place to exhaust the bilge blower anyway. Perhaps higher up on the side of the vessel to avoid mixing potentially explosive gases with hot exhaust.

 

[ripvan1]

Good point, but would that be a problem if using blower only before starting engine and apparently they shouldn't be used with motor running - I do get your point though and will look for another exit.

 

[Adamastor]

3/4" is not going to work. Period.
Better practise would be to put a cowled fitting like a Vetus Scirocco with a decent drain loop right up to the coaming of the cockpit. The cowl will keep spray and mizzle out, but proper waves popping in for a visit will be actively discouraged from making the trip up the drainage loop.

 

[ripvan1]

Yes will go for one similar - but where to position it while taking in mind sarabandes warning - side deck ?