How much Float does my 1979 19-6 have in it?

[imonna 19 6]

Hello all,

I am looking adding a an automatic bilge pump to compliment my manual one and that has me wondering...

Just how much float capability does my  hull have if it did get ruptured, assuming it is still in factory condition?


I know that when I look into the inspection hatches forward and aft on both the port and starboard sided I see foam.    I was told these boats  where pretty well unsinkable.

Anyone have any experience or comments.

Bill

[GoneFission]

If the foam is dry, you could cut an Aquasport in half and the halves would float on their own.  If the foam is waterlogged, as the EPA might say, your mileage may vary...  Aquasports are pretty unsinkable in general, and will float if filled with water or capsized.

[Capt. Bob]

http://www.classicaquasport.com/gallery ... 575/page/1

[imonna 19 6]

So assuming dry foam and all follow up question would seem to answer itself.

This boat will be in a rack storage style system, where if periods as long as 24 hours it will be docked and unattanded (between when I am  done using it and when the marina opens back up and pulls it).  I currently do not have am auto bilge and was considering putting one if to ensure my boat doesnt sink at the dock if there is a problem.

Sounds like this may not be necessary.   any thoughts.

[fitz73222]

Bilge pumps are like seatbelts; you don't need them till you need them... Is it worth $150 investment to save an outboard powerhead and electrical system? Boats get hung under docks during a rising tide all the time. Because our boats are "self bailing" the reverse occurs rather quickly when the scuppers are only a couple of inches above the waterline. So a five inch rise in tide puts the scuppers underwater and she starts going down as the tide comes up. Contrary to popular debate, once the process starts it won't stop. On our older open transom boats its all she wrote once the water clears the transom. Since Aquasport did such a fantastic job of keeping the bilge sealed from the upper deck; that huge "bubble" wants to rise to the top as the water fills the upper deck causing the boat to roll over. I've seen it twice with the same 22-2 years ago because the owner would neglect to make sure that the tilted up outboard lower unit didn't drift under an overhanging dock he had along his bulkhead wall. The first time we didnt figure it out; the second time we did.

[MarshMarlowe196]

Bilge pumps are like seatbelts; you don't need them till you need them... Is it worth $150 investment to save an outboard powerhead and electrical system? Boats get hung under docks during a rising tide all the time. Because our boats are "self bailing" the reverse occurs rather quickly when the scuppers are only a couple of inches above the waterline. So a five inch rise in tide puts the scuppers underwater and she starts going down as the tide comes up. Contrary to popular debate, once the process starts it won't stop. On our older open transom boats its all she wrote once the water clears the transom. Since Aquasport did such a fantastic job of keeping the bilge sealed from the upper deck; that huge "bubble" wants to rise to the top as the water fills the upper deck causing the boat to roll over. I've seen it twice with the same 22-2 years ago because the owner would neglect to make sure that the tilted up outboard lower unit didn't drift under an overhanging dock he had along his bulkhead wall. The first time we didnt figure it out; the second time we did.

My thinking- Given that the bilge is completely sealed, how would a bilge pump prevent the scenario you're describing?  Even if the bilge wasn't completely sealed, seems like a bilge pump, unless it was installed on the deck (which I guess would make it a "deck" pump at that point), would only exacerbate the tendency of the boat to roll over by means of a "bilge bubble".  

Seems that any boat, self bailing or no, would have a hard time staying afloat right-side-up while its pinned under a dock during rising tide.  You'd have to have some serious bilge pumps.

Buoyancy plays a role in whether or not a boat will sink.  It would seem that with more of the boat under the waterline, the more apt it would be to sink.  Not always true-

Any body of arbitrary shape which is immersed, partly or fully, in a fluid will experience the action of a net positive vertical force originating from the depth-dependent liquid pressure. This vertical force is termed buoyancy or buoyant force and is equal in magnitude, but opposite in direction, to the weight of the displaced fluid.

By that logic, the more the boat is submerged, the "lighter" it becomes.  BUT- since the bilges of Aquas are generally sealed, the foam doesn't really play a part in keeping the boat afloat until it becomes submerged as well (ie- the bilge takes on water).


My Dad sold a 19-6 to some young guys (well-they were young in the 70's) and they took the boat offshore.  The boat began taking on water because of a faulty drain-plug, and they abandoned the boat.  The boat was found 3 days later, floating right side up and full of water.

http://www.classicaquasport.com/gallery/showphoto.php/photo/2876/sort/1/cat/575/page/1

Proof in the puddin'.

[gran398]

Miss Marco's hull was "sealed." Except for the chaise run. It was supposed to be sealed, but had a hidden hole at the rear the size of a golf ball.

Bottom line the hull was FULL of water. Dumped it off the trailer. Good thing it was still hooked to the trailer...it was basically sunk.

Will never again own a boat without a bilge pump. A good, BIG auto bilge pump. Or two.

[fitz73222]

My definition of sunk is when my powerheads are underwater, whether upside down or right side up. I would be less concerned about what physics law has been endorced or violated. Archimedes didn't have scuppers in his theory.... You make a good point about the pump located on deck which is exactly why we installed a 2000 gph pump and float switch on the deck and made a pretty little box for it so you didn't have to look at it all the time.

[MarshMarlowe196]

I would be less concerned about what physics law has been endorced or violated. Archimedes didn't have scuppers in his theory....

A "Law", used in this context, is like the "law" of gravity- it doesn't matter how you feel about it, the law applies in all situations.  Archimedes may not have used Scuppers in his test, but Aquasport did-



This test shows that below-waterline scuppers alone (even in combination with an open bilge drain hole) will not make a 19-6/200 "sunk", even the powerhead would still be above the water, as shown in the picture.  Now- pinning a boat beneath a dock would definitely change the results.  Once the water spilled over the transom, as stated earlier, that's all she wrote, with the bilge/deck pumps probably having little effect on whether or not the boat capsized due to the upward force of the air pocket in the bilge.

... which is exactly why we installed a 2000 gph pump and float switch on the deck and made a pretty little box for it so you didn't have to look at it all the time.

Not a bad idea.  I'd like to see that  :)


To avoid censoring, and to answer the OP's question-  A bilge pump in your boat is always a good idea.  Like Gran said, it keeps your stringers dry and keeps your mind at ease.  I wouldn't run a boat without one.

[gran398]

Good thinking by all, good discussion.

Censoring? Just checking...do we reside "en Chine" ?


No thank goodness...its the good 'ol USA.

 

[imonna 19 6]

ok.  Sounds like a second bilge pump, one that is auto is on the list for my April tasks.

Thanks all for the comments.  

PS.  I hit 40 yesterday and the admiral got me abirthday present in the form of a new gas tank, so that project should start in the next few weeks

[Capt. Bob]

Well you've heard it all but my only experience with a "sink" /"scuttle" was caused by a leaking bait well thru hull supply hose. You're on the right track with an auto bilge but if you have any hull penatrations below the water line, I'd worry more about them than the scuppers.

Just my thoughts.

[John Jones]

but if you have any hull penatrations below the water line, I'd worry more about them than the scuppers.

You mean like my scupper drain thru-hulls that the hose clamps had completely rusted away and did not exist anymore?

[Capt. Bob]

Only if the hoses fell off.

[marco]

Long story short .........pumps are cheap.........powerheads on the other hand are not..........take everyones best advice, put in a pump and a big one at that and a damn good float switch :study: with 100% stainless hose clamps!!!!!!!