Topic: Thru hulls - how many is enough...

8 through holes on my boat- all on the starboard side like swiss cheese.  i plan to patch all from the inside before installation of the interior.  (i don't have an inboard engine).

for an emergency bilge pump you can install a Y valve on your engine intake with a hose running in the bilge, as advised by donald street and others.

why not try the head intake off the engine intake?  you could always turn off the head intake while running the engine if you're concerned, provided the valve is easily accessible.

Re: Thru hulls - how many is enough...

I have 8 underwater thru hulls(2 head, sink, engine intake, knotmeter, 2 cockpit drains, prop shaft) on my contessa and to be honest i do not worry about them.  They used to be all bronze with ball valves but i have been replacing them with marlon thru hulls and valves if they have showen any wear or corrosion.  Marlon = no corrosion.  Thru hulls should not worry you if u carry emergency plugs and ensure that the valves are not seized, there are many other things that are more worrisome to me for instance teeing of the engine intake for the head.  I would much rather have 2 seperate throughull fittings rather than a 4 meter hose snaking its way through my boat under the floor from the engine intake to the head and the extra joints at the tee fitting.

For the emergency bilge pump, i carry a bucket which is much cheaper, simpler and faster than using the engine(which i estimate only moves a couple of liters of water per minute).  I only plan to use the bucket if my electric pump and manual pump both fail, which would suggest there is something clogging them down in the deep dark cavern so i wouldn't want to risk my engine's pump anyways.

Re: Thru hulls - how many is enough...

If you had a 4 cyliner honking away, you might move some water.  But the engines typically found in the cramped "engine room" on these Contessa's don't move all that much water.  Realistically, my Wilcox Crittendon Imperial 51 head will move more water.  A 5 gallon bucket will run the engine for a few minutes (testing in the driveway....)  Better to set yourself up with a double redundant electric setup (no I'm not crazy, what else are you going to put in the bilge, besides the rum tank) and a big manual sucker.

Re: Thru hulls - how many is enough...

Great discussion!  I have no speed log, hole is glassed up, so I have seven actually underwater: two head, one sink, engine intake, two cockpit, depth sounder.  Just above waterline: bilge and engine exhaust.  If I was going to get rid of one...hmmm, not sure I would, I like them all! Maybe get rid of the depthsounder, change to one that does not need a hole (the transom mounted...and I thought I read in Practical Sailor about one that just sticks on inside of hull, will look for that issue1)
All mine are proper thru-hulls, with wooden plugs tied to them, I keep them greased and operated them every week at least...if you ever get a hole in your cockpit drain hose or bilgepump hose, you will want to be able to close them off to quickly make a repair and then want to be able to re-open them! ;-)

Re: the engine ones: I installed a y-valve on my raw water engine intake, and I use it to flush the saltwater out after a sail, or yes, to run it on the hard and watch the little propeller spinning in the air as I put it in gear...and a five quart (or approx. five litre for you metric people) takes about a minute and a half to empty...so one could use it to help rid water out of bilge if bilgepump is cloggged, but I agree, however, I believe that's where my raw water strainer will help, as it will prevent crap from trying to unseat the impeller, which you certainly don't want at that time!  I didn't have a strainer, but re-installed the old one (Vetus) old owner had removed, and find it works very well.  Engine runs at a perfect temperature, stays on the cooler side, if my temp guage is even accurate!  I go by feel of the engine hatch under my bare feet!

“You get a boat for only one reason, because you want one.  If you’re worried about being practical, forget boats.”

Re: Thru hulls - how many is enough...

Eight ? I know things are bigger in the US but that sounds like a lot, I have three:

Speed/log impellor
Engine seawater intake
Cockpit drainer

Apparantly one of my previous owners had a phobia about holes in the boat and glassed over the others, hence porti-potti and bowl inside; basic but safe I guess.

Cheers
Andrew

www.contessa26moonshine.me.uk

----------
If the memories are better than the dreams then it's all over.....
www.contessa26moonshine.me.uk

Re: Thru hulls - how many is enough...

Yes, us Canadians waste our water! ;-)  I too would get rid of the head if I could, but being a girl, well...
and if no sink, yes, there're three you could eliminate right there, but aren't your cockpit drains two holes/hoses?  I don't think you over there like to hang on to your water that much?!  You do have the teak grate and the higher sill, mind you! ;-)

How long have you had Moonshine?!

“You get a boat for only one reason, because you want one.  If you’re worried about being practical, forget boats.”

Re: Thru hulls - how many is enough...

Opps, no insult intended :-)

I've only had Moonshine since August of this year and currently working through a long list of winter jobs to get the boat back into the water for next sping and hopefully make the Contessa 26, 40 year anniversery get together in Lymingtopn later in the year.

Hopefully will get the Yanmar 2GM20 engine back in with new engine mounts before Christmas into the reglassed engine beds.

I have to admit that I've dressed up as Santa and made a trip down to the local chandlers for two Lewmar self tailing winches, new autopilot and NASA instruments.....well Christmas only comes once a year.

Cheers
Andrew

----------
If the memories are better than the dreams then it's all over.....
www.contessa26moonshine.me.uk

Re: Thru hulls - how many is enough...

I told the fellow who runs the group there I am going to do the Jester Challenge in 2010...so I'll see all you Rogers' boats then! ;-)
Good luck on your list!  By the way, the list never ends...did anyone tell you that before you bought your boat?! No one told me!  hee hee!
Merry Christmas to our boats...that's a good idea!

“You get a boat for only one reason, because you want one.  If you’re worried about being practical, forget boats.”

Re: Thru hulls - how many is enough...

OK, here's a question to generate discussion...  how many thru-hulls does your boat have below the waterline? 

My project currently has 8, as follows:
Head intake, stbd fwd
Head discharge, stbd fwd
Speed log, port fwd
Depth sounder transducer, stbd midships
Sink drain, port midships
Engine water intake, port midships
Cockpit drains port & stbd aft
... plus the engine exhaust and bilge pump discharge within 6" of the waterline...

This is alot of holes in a small boat (I had fewer in my last boat, a 37' trimaran!)  I'd like to get rid of a few if possible - here's a few ideas I'm kicking around:

- Replace the depth sounder transducer with an inside the hull hockey-puck style transducer.  (The current unit is shot and needs to be replaced anyways).

- Chuck the speed log (also currently shot).  I don't race so don't need 0.01 kt precision.  While GPS only gives speed over ground (as opposed to speed thru the water) and so can't replace a log, I find that once I get to know a boat I can usually estimate speed thru the water pretty accurately.

- Tee the head intake off the engine raw water intake.  My concern here is drawing air into the engine water pump at high RPMs.  Is this a valid concern?  Would a check valve in the head intake line after the Tee solve the problem?

- I have also thought about switching to a porta-potti, as the current marine head isn't set up with a holding tank anyhow, but have mixed feelings on this one (a whole separate topic which I won't get into now...) 

Anyhow, I'm curious to hear other's thoughts and solutions!  Thanks!