Bilge pump dilemma

[zeilfanaat]

I want to install an automatic bilge pump in my Pearson 30 and I am weighing different options…
Do I install an electric diaphragm pump "high and dry", with a pickup hose/strainer going to the bilge and separate float switch, or should I go for a smaller, self contained centrifugal unit (like the ones made by Rule).

I have a diaphragm pump ready to go, but it is bulky and hard to find a good place to install it. The cockpit locker seems a logical place, but it wouldn''t be very protected from fenders, lines, and boathooks. It also draws quite a bit of power (7A) and doesn''t have a very high capacity (4.5 gal/min = 270 gal/hr). Do diaphragm pumps perform closer to their rated capacity than centrifugal pumps?

The smaller units seem to have a higher capacity and draw less power, which seems an advantage to me (I understand that smaller boats need bigger bilge pumps). Are centrifugal pumps more prone to back siphoning or other failure? Anyone have any experience with these pumps?

Also, is there a rule of thumb on the longest hose run that a typical pump can handle? I''d like to discharge through the stern, but with a hose run of 15 ft or so, I am not sure that''s feasible. Would it be better to exit through the side (with a vented loop). By the way, would I still need a vented loop with the diaphragm pump or does its design act as a siphon break?

Thanks for your insights!

[VIEXILE]

8 years ago I installed a Rule 360gph internal switch automatic pump in my 5'' deep bilge. I also have a whale gusher (hand pump) installed in a cockpit locker that moves a lot of water, but your arm wears out after about a half hour. I put a Rule 1500 about 8" above the bottom of the bilge and wired it to a switch on the elec. panel. The 360gph draws as little amperage as you can imagine and I''ve never had to turn on the 1500. A couple times a year I dump bilge cleaner in, take the hose off the raw water intake and fill the bilge and run all three pumps to make sure everything is clear and clean. Skip float switches. One little piece of crap or a hose laying across them and they''re useless. They don''t seem to last long, either......

[clayton]

I use a diaphragm pump to vacumn out my rather shallow bilge (Pearson 10M). I use a 2,500 gpm cintrifugal pump as my main trouble pump. I would not exit a bilge pump from a side discharge - stern only, because of the chance you''ll be heeling to that side when you are pumping.

[halyardz]

IMHO Viex is basically on target. You might wish to move up to a 500gph unit. Float switches are basically trouble and finding out late that one is fouled/hung up, is not a nice thing. I carry a separate backup battery and have a switch to route the pump to that if for any reason the main banks give out (also serves other purposes)