floor replacement

[jerni21]

hi i have a '71 johnson tri-hull and the floor is starting to rot, enough so that i cant even screw the seats down without the screws pulling out, so how hard of a job is it to replace the floor and what does the floor sit on? and is there a chance for those pieces to be rotted too?? also how thick of plywood should be used? and does it have to be marine grade and where to get it? sorry for all the questions but i wanna get this done right and i figured u guys would lemme know how to do it right and its not so bad i mean u can stand on it but i wanna know whats under the plywood b4 i start it, because i dont wanna trash the hull so any responses would be greatly appreciated thanx alot

 

[2manyboats]

Re: floor replacement

You can find a boatload of info on this topics by doing a search on this site. Best way to start. Then take up the old floor, plan on finding rotten stringers needing replacement, then step back, take a deep breath and dive into a real educational project. This forum has a lot of guys either doing or have done the same. They're a lot of help, and only a little abusive .

 

[tashasdaddy]

Re: floor replacement

ok now you're in the right spot for help. you ususally have 1/2' plywood floor, under it are stringers that run from bow to stern. it's a messier job and hard. be prepare to change clothes in the garage or basement, cause she ain't gonna let you in. also wear a mask. and safety glasses.

 

[tashasdaddy]

Re: floor replacement

Oldhull is in the same process you are. he's just ahead of you, and has a trihull.

 

[JasonJ]

Re: floor replacement

Click my link, it should help a little...

 

[jerni21]

Re: floor replacement

thanx alot jason j tjis makes me realize how big of a project it really is, it might be more work than its worth so maybe ill get another season or two out of it before i start something like this, i thought all u had to do was rip out the plywood and throw some new stuff in there but if the stringers are rotted then its more work than i planned if any1 else has any tips please lemme know

 

[2manyboats]

Re: floor replacement

Sometimes ya just gotta cut and run...

 

[jerni21]

Re: floor replacement

lol yea

 

[JasonJ]

Re: floor replacement

It is a lot of work. I would not have done it unless I had the specific goal of my end result. You have to really love the boat or have a specific need that the work would be worth it. Otherwise, there are a million other hulls out there, and you may find one that still needs the work but would better suit your needs. Good luck...

 

[tashasdaddy]

Re: floor replacement

Jerni, if the floor is getting soft, and you don't want to do it now, get a pieces of 3/4 exterior plywood. cut it the width of your boat, so you hace a 4' x 5' or so, piece. bolt, not screw, your seats to it, go on until you step thru the area not covered. remember rotted wood holds more moisture and will increase the wieght of your boat and it's performance. just a shade tree sugggestion.

 

[jerni21]

Re: floor replacement

yea, i noticed a slight decrease in performance, good idea though for the meantime maybe ill just put a pieco over it

 

[blackwaterstout]

Re: floor replacement

I'm kinda in the same situation as you are. The floor in my '79 MFG is soft and I can not get the seat pedestals to hold. The floor needs replaced but I can't stand the thought of getting involved in such a repair. I have so many big plans for fishing this year that I want to put it off another year so I can relax and enjoy myself. We've been tossing around the idea of just cutting a sheet of ply to fit and bolting the rear seat to it. I know it's gonna add needless weight and will decrease performance a bit but I'm not too concerned about loosing a few MPH. It's a fishing boat not a ski boat. I don't want to do something that poses a huge safety risk so I'm trying to look at from both angles.<br /><br />Let us know what you decide to do.

 

[jerni21]

Re: floor replacement

i have a ski boat so i dont want to lose any performance but if i have to i will the thing is i wouldnt mind replacing the floor but what scares me is the thought of having to replace the stringers, i mean im good im fiberglass and all but i just never done anything like this before so im kinda scared to attempt this because i love this boat and dont wanna screw it up, still contemplating wether or not i should do it

 

[tashasdaddy]

Re: floor replacement

your first friend is cardboard from appliances boxes. cut templates out of it, if you are good w/ fiberglass you've got 80 % already beat.. you know how to work a saw, grinder, sander. educate your self here and go for it. think how proud you will be when you saved the old girl, rather than her going to the dump. good luck and be patient

 

[jerni21]

Re: floor replacement

thats the truth id really rather save it and make it good at least until the motor quits if not longer

 

[brownies]

Re: floor replacement

71 Johnson Tri Hull....wow....never thought I'd ever meet another owner.<br />Always like to call shops looking for parts. <br />"It's a Johnson engine?"...."no, it's a Johnson boat".<br /> I just took the floor out of a different boat (three days ago). It was about an 8hr job removing, pulling out all the floatation (that stuff works like a sponge) and grinding the fiberglass away from the stringers and hull to start again fresh.<br /> Installation about the same amount of time I figure, which will include re-fiberglassing over the new floor and grinding it smooth for carpet. (drying time doesn't count). <br /> Does that Johnson have fiberglass over the floor wood?

 

[jerni21]

Re: floor replacement

no it doesnt, if you could do u have any pics of the job your doing??? i wish it did have some fiberglass over the floor maybe it wouldve lasted longer...

 

[brownies]

Re: floor replacement

Not sure how to post a picture on here. Be hard to get one right now though. Boat is upside down with the top edge of the hull just a few inches above the floor.<br /> I can get one, but, it will be at least end of next week.<br /> I probably should not have flipped it without the floor being in it, but, it still has the stringers in it. (it was solid, but, it was wet). No way for it to dry unless the floor was removed. Had to get all the saturated floatation out.<br /> Turned it upside down so I could work the hull and get it ready for paint....more "air out" time for the inside.