Tuesday, January 6, 2009

Electric Bilge Pumps.........

From the West Marine Adviser; "Virtually no boat has a bilge pump system which is large enough to keep up with a leak caused by hull damage. Bilge pumps are designed for small quantities of water and are not damage control pumps like the ones Coast Guard helicopters drop." Some figures to keep in mind.

Rule 2000 = 2000 GPH, allow 50% efficiency (very generous, 25% more realistic.) due to hoses etc. = 17GPM = 1000GPH.

2" hole 3' under the waterline (tru hull hose breaks off etc.) = 136GPM = 8160GPH

4" hole 3' under the waterline (ding a container/reef etc.)= 544GPM = 32,640GPH = block the hole or its swimming stations.

Figures from Calder. Worth reading P 219 of his Cruising Handbook (as well as the rest of the book). Sobering stuff.

I will look into the following system, but I'm not sure how I can incorporate it;

Fast Flow Pumps

1 comment:

builder said...

Like that FastFlow pump product. great idea. Gotta remember that one.

Dont forget, many "typical" bilgepump ratings do not account for any, or enough, rise for the vented loop discharge that should be installed. The higher the loop, the less GPH.