Re-doing a floor in a 1986 bayliner Capri 1750 bowrider

[Nbo]

Does anybody know what size of flooring that Bayliner used in an 86 1750 Capri bow rider would it be 3/4” or 1/2” Marine grade plywood

[ken51k]

1/2 " plywood, for the floor you don't need marine grade.

[Nbo]

Thank you so much

[TX H210 SS]

When I replaced flooring I used 1/2 treated, not marine grade. I also coated with Behr sealer and let dry well before installing. I treat the hell out of edges on precut pieces and inserted silicone in all screw holes before inserting stainless screws.

[swilson]

Just curious here, how come yall say not to use marine grade? I too am going to have to replace the floor in mine. I was dreading the price difference between treated and marine grade.

[Pcpete]

Imo, and having built boat as part of a misspent youth, marine grade plywood period. It has to due with the glue, species of wood and number of plies. Marine grade Fir is my preferred. To be extreme, you probably wouldn’t use pressboard because you know what happens if it gets wet. It’s kind of the same thing. There are some who will point out that exterior plywood, like CDX (C grade ply on one side, D grade on the other and exterior glue), is just fine. However, half inch CDX isn’t ment fo walking on and will break down over time.
Once you have dry fit each piece, soak the plywood in a mix of 50/50 catalized resin and acetone and keep it going as long as the wood absorbs it, especially the edges. When you install it use a bedding compound like lifecaulk or 4200 but not, no way a silicon on every screw. Do not use stainless steel screws where they will not have access to air, they will rot out, use bronze. Once you have the deck in, glassed and whatever surface, like marine outdoor carpet (Perfectfit.com is a great source) Then use stainless steel screws to fasten the upholstery but, use bedding compound on every one because each fastener is a path for moisture to get inside the plies of that deck.
Be sure to check out the other reinforcement structure like the stringers and transom. The area around the drain hole is a common issue. While you are there, assuming everything is solid, take a piece of pvc and fit it so it goes through the wood to the fiberglass transom then install it with either 5200 or 4200 and eliminate the risk of a soft transom starting there.

[driz]

Just curious here, how come yall say not to use marine grade? I too am going to have to replace the floor in mine. I was dreading the price difference between treated and marine grade.

I know it doesn’t mean much with a glass boat but treated wood today ain’t the same stuff your father used. The formulation changed back in the 80s to suit the tree huggers. The end result is that if it’s left in contact with aluminum it well eat the aluminum. Worth knowing right? Also have you looked at the quality of that stuff? It doesn’t inspire much confidence, like they looked for the crappiest stuff to use they could find.
Also while you got that deck off it’s the time to take a piece of scrap pvc , something like 1/2” and pgunch a few cores down to the center bilge of the hull. If it comes up wet and heavy now the time to make it go away if it’s wet. Pool noodles make a decent substitute which many use. Hopefully you don’t need to do that though.

[Pcpete]

Do not, under any circumstances, use treated plywood or lumber. It may sound like a logical choice but it isn’t “sound” for boat use.

[swilson]

Great information presented. Thank you.