[Public-list] Cockpit drains above water line

J Bergquist jbergqui at gmail.com
Wed Mar 14 08:59:39 PDT 2007


Rachel-

One problem I have observed on my boat is that my cockpit drains
sometimes get clogged from leaves in the fall. Given that I don't live
on my boat and it's tough for me to get there every day, it's tough to
keep all the leaves out of the cockpit.

Now, my cockpit drains have a pretty fair and vertical lead angle. I
assume they are in the originally design locations. I replaced the
ball valves last spring with new ones. Getting the hoses on the new
valves was a bear of a job. Not one I considered fun. I do not have 90
degree elbows on my valves.

How far outboard or aft do you have to go in order to put your
thru-hulls at the waterline? If you did this, would the thru-hulls
even still be in the engine compartment? What would the lead angle of
the hose look like? I'm guessing it would be much less vertical and
much more horizontal, resulting in a much less fair lead for drainage,
higher frictional losses in the plumbing, and as a result a slower
draining cockpit. I'm also guessing you'd need 90 degree elbows on the
thru-hull in order to even get the hose to connect to them. These
hoses don't bend easily. At least not the ones I used...

If you check out that triton site I sent earlier, you'll see that he
used 90 degree elbows. And he still kept the thru-hulls more or less
in the same place. I would hate to try and clean or plunge leaves out
of those cockpit drains with that plumbing angle.

One of the main positives on having a more-or-less vertical lead on
the cockpit drains for an oceangoing boat is that if you do get
swamped by a big wave and have a cockpit full of water, speed of
drainage becomes important. Having a direct, vertical lead angle for
your drains will make a significant difference over having a 2 90
degree bends and a more-or-less horizontal run of hose in terms of
friction in your plumbing.

I haven't heard of an Alberg 30 sinking because of a busted cockpit
drain thru-hull. I HAVE heard of one sinking (or filling up with water
on the hard) because of clogged cockpit drains (tragically, this
happened last fall/winter to one of our Chesapeake Bay members...) So
I would be REAL careful about changing that lead angle if I were you.

My guess is that ease of drainage is the main reason why Alberg drains
are where they are. The boat was designed as a coastal and sometimes
bluewater cruising design. The main purpose of cockpit drains is to
drain the cockpit. The faster and easier that happens, the better. So
the lead angle was kept vertical.

That's just my guess.

I'm interested to hear what you finally decide.

Later,

J Bergquist

On 3/14/07, penokee at cheqnet.net <penokee at cheqnet.net> wrote:
>
>
> On Wed Mar 14  8:15 , 'Mike Lehman' <sail_505 at hotmail.com> sent:
>
> >Rachel,
> >
> >I do not know why you would go to all of the effort to do this. I have never
> >seen an A30 with cockpit drains above the waterline. Gate valves are a bad
> >thing and should be replaced. Moving the thru-hull fittings makes no sense.
> >These boats have survived, without problems, for 40 years. If the thru-hull
> >fittings are bad replace them. If the plywood backing plates are bad,
> >replace them too.
>
> Mike,
>
> As I mentioned, I am in the process of replacing the gate valves, backing plates,
> and through-hulls, which is why I'm posting about it now.  While I agree that the
> A-30 is a great boat, and has survived for 40 years as is, there are certainly
> things that I would do differently (and the manufacturers might too, given
> hindsight).  Now that I have the whole set-up out, I see no need to slavishly
> duplicate it without considering changes or improvements.  I mean, I'm not
> putting gate valves back in, so I'm already changing it from original.  I'm also
> not changing just for the sake of change, or without forethought and research.
>
> I hope this helps to explain why I might go to the effort of asking about a
> potential change, and might even make a change in the end.
>
> Rachel
> _______________________________________________
> These businesses support your Association:
> http://www.alberg30.org/store/A30supporters.html
> Please support them.
> _______________________________________________
> public-list mailing list
> public-list at lists.alberg30.org
> http://lists.alberg30.org/listinfo.cgi/public-list-alberg30.org
>

 1173887979.0


More information about the Public-List mailing list