1978 sea nymph resto

[kino986]

Hi guys been long time since my last post. I acquired a 1978 sea nymph 17 foot deep V hull recently and decided to do a full restore due to transom holding a johnson 115hp was completely rotted out.
i pulled motor and got what was left of the transom out and noticed the floor was also soft so i pulled that out as well.
My main question is there was not a single trace of flotation under the floor. I have got to the point now where i am ready to install new floor and deck but the flotation has me stumped. Pouring 2 part foam doesn't seem practical to me due to being a V hull therefore how does it fill every void between stringers. Any experience with these old tin cans and flotation under deck? Since no flotation was under floor do i lay new floor down in hopes under cavity is "air tight" and deal with the loud noise if it pertains to draw a lot of noise or what?
im stuck please help. Im trying very hard to upload pictures but having trouble.
boat looks similar to a starcraft 17ss

 

[kino986]

[No message]

 

[kino986]

[No message]

 

[Scott06]

Is it possible due to age of boat you are replacing the floor for the second time? It's unlikely there was no foam under there from the factory, thinking floor was done before and foam not replaced.

Two part foam foam expands to fill voids, just need to drill hole in floor into each large cavity , glass plugs back into floor after foam work is done

 

[kcassells]

In any event the foam will provide a quieter ride and keep the boat afloat in the event of an accident. No brainer.

 

[kino986]

thank guys, yes I do believe that the floor was redone at some point and foam was not added back. I understand foam has it benefits in sound deadening and structurtal support. I will have to just bite the fact that I need to drill holes in a brand new floor to get foam inside. I will move thread over to see if anyone

 

[kcassells]

2 lb foam is all you need. It does not have any structural benefits until you move up to 4 lb and higher.
Foam will keep the boat afloat.
So as far as drilling holes in the new deck is a brain twister and I get it.
You will need to drill 2 holes per compartment, hopefully you know what they are.
Put your boat on the trailer on a tilt as best you can. 1 hole at end of compartment lets the air vent the other hole is the fill hole for the pour in foam.
Keep posting pics and asking questions.

 

[jbcurt00]

Lots of Starcraft (Sea Nymph cousin) have detailed their rehabs. Most used rigid insulation to avoid drilling holes in a new deck, and allow water that gets below decks to get out...

Look thru some of their rehabs
https://forums.iboats.com/forum/owners-groups-by-manufacturer/s/starcraft-boats

And here
http://forums.iboats.com/forum/owne...ft-rebuilds-and-restorations-they-re-all-here

 

[kcassells]

Good man JB!

 

[kcassells]

You can save the plug from the hole saw and reuse it. the hole should be @ 1.25 or 1.50 large. The foam will come up out of the vent hole. You can cut it off then use a drill with a wire brush attachment to bring down to height for the saved plug to go back in.
In any event once closed cell foam is cut it then become open cell, which will absorb water. That being said you need to wet out the new exposed ply and foam with poly or EEEpppoooxxy What ever you used on the new deck will be best.
If reusing the plug turns out to be a pia, then simply fill the recess with glass enforced poly peanut butter to deck level and sand smooth.