"Bruce" wrote in message
...
On Fri, 18 May 2012 22:20:08 -0400, WaIIy wrote:

On Fri, 18 May 2012 13:01:51 -0400, "Wilbur Hubbard"
wrote:

"barret bondon" wrote in message
...
Why did the engine run at all ?
Atomic 4 in a 1977 27 foot Columbia. Boat had sat all last summer.
Engine started and ran fine for half an hour, got us 200 yards
outside
the breakwater ( not a rough sea, but more motion than in the harbor)
where it quit. I pulled a fuel line; lots of water in the gas.
Q: Why did it work at all ? Assuming the fuel/ water mix homogenized
out of the harbor and got drawn into the pump doesn't tell me how to
prevent this on the next boat. Where is the intake on most tanks ?
Water sinks to the bottom of course, and I assume the intake is at
the
bottom of most tanks; in that case I never would have left the dock.

(not my boat, BTW !)




Water in fuel tanks is a common problem. It would seem to me that
built-in
tanks should all have a small sump at the lowest part with a drain
valve
to check for and get rid of any water that collects from condensation
or
water in the fuel from dubious sources.

It's a gas tank, not a water heater.



In lieu of that, you should install a large fuel/water separator filter
in
the intake line and check and drain it frequently. Your theory of
'frothing' or mixing is probably why the motor ran OK for a while but
when
things got a little rougher the engine quit because enough water got
into
the carburetor so fill the float bowl.

Wilbur Hubbard

This is not an uncommon happening at all. You have an engine with fuel
throughout the system, at least back to the tank. You start the engine
and it begins to use fuel and eventually it begins to draw fuel from
the tank. Except that it isn't fuel, it is water - water being heavier
then fuel collects in the bottom of the tank where the fuel line inlet
is located. When this water from the tank reaches the carburetor or
injection pump, as the case may be, and the carbie or injectors start
to deliver water to the engine the engine quits.

Finally water does not mix with gasoline or diesel fuel in any
significant manner. Try it, put some fuel and water in a mayonnaise
jar and shake it up. as soon as you stop shaking the water settles out
of the fuel.

And before someone corrects me, yes, it is possible for fuel and water
to form an emulsion, but not by pouring water into a fuel tank.
--
Cheers,

Bruce



Hey, I'm amazed, Bruce. This is perhaps the very first time I have noted
you contributing something that made sense.

I still would have a sump and a drain valve in any internal tank on my
yacht (if I had fuel tanks in the yacht.) It's so dumb to NOT have them
just because there's a miniscule chance the valve might leak a little fuel
into the bilge. Only a dumbass would neglect to close and secure the valve
with a wire or a tie-wrap. etc. This is a case where insurance companies
can impose their will on sailors and boat builders because of catering to
the lowest common denominator dummy who would allow fuel to leak into the
bilge because he was too stupid to close and secure a simple valve.


Wilbur Hubbard