Decking Repair Experience
 

I am posting this information for reference and comparison if it might help out someone. --- I have a ’93 Shabah 212Z. It had been uncovered and exposed to weather for at least a period of time so I decided to work on upholstery and carpet.

In removing the old carpet, and examining the plywood floor – I discovered concerns—

 The plywood deck floor surface had originally been coated with a layer of fiberglass to protect it from water—this fiberglass coating had mostly cracked and checked and no longer protected the plywood. As a result- I found the plywood from behind the pedestal seats to about the front of the motor had some surface damage and some minor degree of warping. I decided to replace that portion of the floor. This is also the area where the under-floor fuel tank is located.

 I removed the ¾” plywood over the fuel tank (the tank lays flat in the center of the floor, just in front of the engine). The fuel tank is held in place by 4 aluminum angles which are screwed into the subfloor. The factory did not use stainless-steel screws for these angels, the screws had rusted, and as such, the angle brackets were mostly loose.

 I found the plywood stringers under the plywood deck flooring to be of great quality marine redwood-type plywood and this plywood was all in wonderful condition. I also discovered the plywood decking, on top of the stringers, had been stapled by the factory to the stringers- but again, they did not use stainless-steel staples. The staples used to attach the flooring to these stringers had mostly rusted and as a result, the floor was now only partially attached to the subfloor stringers.

 Where the plywood decking joined against the hull, fiberglass was used to attach it. I found the attaching fiberglass had completely broken and the floor was no longer attached to the left side of the hull from the bow for 2/3’s of the boat's length. I believe the cause was due to the flooring moving because of the rusted-out floor to stringer attaching staples.

Repair was not that hard, in all I spent about 8 to 10 hours on it. - I replaced the damaged plywood (3/4” over the tank and ½” for the left and right floors beside the fuel tank location). I reattached the left floor to the hull by re-glassing and matting. I then installed 200 stainless steel screws (2” #8) and thoroughly reattached the decking to the under-floor support stringers (be careful near the hull so you don’t run a screw through it). I used a grinder (5” electric”) to clean off the old floor fiberglass coating and then I poured a new coating over the entire floor, reinforcing with fiberglass matting at the plywood junction locations. The work turned out fine and the deck will be secure and again protected from water.

Another observation-- the factory descriptions shows the sub-flooring completely filled with foam. It is not completely filled. The factory originally injected it through multiple holes in the floor decking, There are big “patties” of foam under the floor and the fill average is about 60%.. This foam looks the same as the Home Depot type available in the spray cans.

Gas tank replacement
 

Rick,

I have to replace my tank in my 94 Talari. I've gotten down to the top layer of plywood, but it appears it's glued to the secondary piece of plywood under it. I can't find any screws in the deck piece. How did you remove the deck piece of plywood over the tank?

Deck repair
 

My experience was with the Shabah-- The plywwood over the tank was a seperate piece. It was screwed into the support frame under it. The flooring was also covered with a layer of fiberglass which required some cutting at the junctions of where the plywood meet. I do not know if yours is similar (I would expect it to be), but if there is an obvious seperate piece of wood over the tank, it may require some cutting and prying to remove. Once it was out, repair was obvious