TOPIC: New member intro

Hello all,
New member here. My name is Ron, I live in Orange County, Ca., married, 2 kids, 2 dogs, 3 tortoises, 6 chickens,... and too many projects.
One of which is my '72 Larson Shark (model 165, I think),I/O 120hp, trihull.
I've just completed a full top end rebuild, replaced the outdrive, new impeller, new prop, serviced the trim system, and (almost) all is well.

to my great dismay, I have discovered that the small "Soft spot" in the floor/deck, is larger than expected, and it looks like I will need to replace the deck. Bummer!, but that's the joys of restoring an old boat I guess !!!

I started to tear out the rotted areas today, and could use any help or suggestions you have. Not quite sure what all of the structure is that I am finding, and I'm sure this will be a fairly involved project.
I'd be glad to post pics once I figure out how to do that using my photobucket pics, so this is my first attempt to post the pics. I hope they work properly....









If you could refer me to any links of past threads showing a floor replacement, I would greatly appreciate it.
(especially if someone has done a floor replacement in a old Larson trihull)

This is what I started with...











Heres what I've got it to now...











I've had it on the water a few times, and enjoy the boat with my family. We even did a week long trip to Havasu in it 1 1/2 years ago, and had a blast.









Now the kids are pushing me to "go camping again with the boat", and I'm faced with replacing the floor/deck. I could use any help finding info and pics on how to do this.
thanks in advance for any replies, and I'll do my best to post pics as I make progress.
Ron

Welcome to FG Ron, glad to have you aboard. I can't think of any good "floor" threads right off hand, (not to say there aren't any, I just can't think of any right now). Looks like you've done a good job bringing the Larson back, thanks for sharing the pics.

If you'll look in the upper left corner of the screen under the header there is a "Research - Restoration" button. Click that and you will find several tutorials written on proper techniques. The one you (and many of us) are looking for on floors is currently being written, hopefully to appear soon. You can also use the Search Forum box in the upper right corner, type in floor or plywood, it will bring up many threads on any subject.

OK here goes.
1 Before pic even though it is an outboard and a Starcraft.


2 Remove entire floor.


3 Build new pieces and water proof the underside and glass it to the hull on top.

4 My bow seats rebuilt, but you may be able to stop at the helm and not replace the bow seats.

5 Recarpet after glassing the entire top surface.

6 Carpet up the sides and reinstall the seats.


A lot depends on the framing underneath. I did not replace the wood in mine. I simply went over the old forms with a second layer of 1.5 oz. woven roving.
I used the same thickness plywood, good exterior grade.
I screwed and glued the new floor down with stainless #8 flat heads, and poly resin.

well, it's worse than I had originally expected.
Not only is the entire port side half of the deck completely dry rotted, but also, the port side half of the transom, and approximately the aft 4' of the port side hull stringer.
I now find myself in need of questioning if it is going to be worth trying to save.

For now,I will continue to remove the rotted wood, consider the practicality of attempting to splice in replacement structure, and try to determine the potential of restoring structural integrity.

Here are some pics of the progressive removal.
Please feel free to share your thoughts.

Whoa stop removing that inner fiberglass skin. You will need that if you go with Seacast or the other one, Nidabond I think.
Is there a way you can grind the cap of the transom and remove all the wood. For removing all the wood, the more rotted the better. Removing decent wood I found difficult, and I actually cut the back of my boat off.
Check out the Seacast website. The have specific instructions for I/O motors.

actually, there is no inner fiberglass skin on the transom. Yes, it was glassed in around the perimeter, but it was never completely covered/encapsulated with glass cloth/resin. kind of strange they did it that way.