T&T: A/C pump - intake - problems/Remedy?

[Robert Phillips]

< Install a back flush fitting to the AC raw water inlet so that a raw
   water
   washdown hose can be fitted when needed. >

If only the yachting world would do what the commercial world does, 
which is have intakes that are clearable from the inside of the boat.  
I installed "sea chests" six years ago and haven't been under my boat 
since.  These are 12" square fiberglass boxes that are glassed through 
the bottom of the boat, one starboard and one port.  The tops of these 
boxes are clear Lexan with a screw in inspection port in the center, 
allowing access into the boxes, the bottom just open.  The port one is 
where all of my through hulls are located so clearing a clog is just 
unscrewing the inspection port and reaching down.  The top of this box 
is 6" above static waterline with the lowest through hull down about 
20", so you have to roll a sleeve to not get your shirt wet, but much 
easier than going diving.

I made them 12" square at the suggestion of my mechanic, so they can be 
painted with a regular roller, but would make them smaller if doing it 
again, probably 8".  There was no discernible change in boat speed 
although there is a fair amount of turbulence in the boxes underway.  
They require venting and while I have had 5/8" vents, these will be 
changed out to 1" vents as there is just too much pressure in the boxes 
in heavy seas.

One added benefit, as if being able to see each through hull and 
clearing them without getting wet isn't enough, it gives a nice view of 
what's under the boat.  Our galley sink drains into the starboard box, 
where all of my exits are located above the waterline -  AC, bilge, 
sink, washer - and there is usually a small school of fish waiting for 
us to do the dishes.

It is possible to do the same thing with a large through hull, 3"-4", 
and T'ee a number of valves off of it and have a pipe that extends 
above waterline on the top, with a pipe cap.  You would then be able to 
push something through to clear it.

Bob Phillips,
Another Asylum. Tortola, BVI