"Capt. JG" wrote in message
easolutions...
"Wayne.B" wrote in message
...
On Mon, 5 Oct 2009 16:41:19 +0200, "Edgar"
wrote:

Anybody have diverters to suck the bilge on their engine and genset
water intakes?

--Vic

This facility is available on some small boat inlet strainers that I have
seen but I think it is a bad idea as you do not want to put dirty bilge
water through your engine, as a modern engine has very small cooling
water
passages and any blockage there means big trouble..
Moreover, the capacity of an engine cooling pump is pretty small in
comparison with a decent bilge pump, which is another reason against such
an
arrangement.
If you want to use the engine to pump your bilge, rig a belt driven high
capacity low head pump that will really shift some water.

I don't have that but know of others who do. The raw water pump on a
large engine will typically pump 30 to 40 gallons per minute or more.
Raw water circulation on large salt water engines is almost always
through a heat exchanger instead of the engine block. If the boat is
sinking you do what you have to do.



I have a Westerbeke 13. It uses raw water to the heat exchanger. I don't
think the 13 is considered a big engine. I've been thinking about making
this sort of connection. I believe I first heard about it in a mag.
article... SAIL or Cruising World.. can't remember. Seems like a good idea
for a last-resort situation.

If you don't have it and the boat sinks, the boat sinks. If you have it,
and it works, the boat doesn't sink. If you have it, and it clogs up the
engine, which then quits, the boat sinks, but you might buy yourself some
time.


Another point worth mentioning is that you must be very careful to watch
progress.
Should the bypass manage to suck the bilge dry you will be running your
engine without cooling water