transom and floor replacement

made in china

Seaman
Joined
Aug 19, 2009
Messages
51
Re: transom and floor replacement

Wow, so glad I found this thread.
I just acquired a 1986 Larson 175 OB, and it has a soft floor near the fuel tank access and the ski pole.
My main concern is the stringers, however seeing that your stringers survived gives me a glimmer of hope. I plan on doing exactly as you did, patching the soft spot for this up coming summer and replacing any rotted stuff this coming fall. But, I won't repaint my boat, my garage and wife won't allow it!

I have a few comments/ideas/questions:

1. Regarding the transom: I saw you used Seacast. I had an idea, what if someone who need a transom replaced used plywood as usual, but bored large holes around every area that bolts/drains/hardware penetrate the transom, and filled those large holes with Seacast to make a composite transom that would resist rot, but would be mostly a traditional type plywood install? Reason I ask, if I have a good transom, I would like to modify the areas where hardware/drain passes through. My idea would be a depth limited hole saw that could hog out the plywood around each hole, and back-filled with Seacast and re-drilled. Basically to buy more time for the transom. Of course, this is only if my transom is OK.

2.Speaking of transom, I did bang on my transom with a wrench tonight, around the drain hole and other bits, and it sounded like hitting concrete, it sounds real solid. Would a rotted transom sound different? Just curious if this is a reasonable way to detect advanced rot.

3. Whats the process involved for removing the "cap"? Is it glassed on? Or just hardware?

4. My fuel tank is in the floor, and it has an access cover. Is that normal? It rotted, as it almost looks like someone added the access door at a later time? Is that how Larson usually installs their gas tank? I'd like to seriously beef up this area next time around as the rot basically started here, I don't think the plywood was ever protected.

Thanks for posting your work, I am now subscribed and looking forward to your outcome!

-Jason
 

SKIBUM1M

Chief Petty Officer
Joined
Jul 17, 2009
Messages
604
Re: transom and floor replacement

Jason,
congrats on the Larson, I really like mine alot
1 The seacast Idea may be a possibility but the reason mine failed was larson did not seal the plywood around the drainplug hole. Make sure to seal this. Also they didn't cover the inside of the plywood very well. Put a few layers of fiberglass on the inside of the whole transom. These two repairs should keep your transom in good shape.
2 check post 339 of this thread to see how to do a core sample.
3 To remove the cap just pull out the rubber strip in the rub rail, remove the screws in the rubrail, then pull off the rubrail. Remove the screws under the rubrail, then use a putty knife to break the silicone and lift off the cap. Oh yeah remove the splashwell drains first(I didn't and they broke)
4 My fuel tank sits on the deck under the back seat but when you redo the deck just make sure you seal the edges of the plywood around the hole.
Good luck with it, have fun, and feel free to ask me anything.
 

made in china

Seaman
Joined
Aug 19, 2009
Messages
51
Re: transom and floor replacement

Skibum, a quick couple questions for ya:

1. How did you make the temp repair to your floor to get you through the first season?

2. Why remove the cap? Just to make things go easier, or a absolute necessity?
 

SKIBUM1M

Chief Petty Officer
Joined
Jul 17, 2009
Messages
604
Re: transom and floor replacement

1 The center was rotted but the sides were supported by the foam, so I cut a piece of plywood that fit between the seatbases from the fiberglass floor in the bow to the back seat. Then I wrapped it in indoor outdoor carpet and laid it down over the remains of the old floor.
2 To do it right I took the cap off because the floor runs up under the bow floor. You could patch it together at that point but I wanted it watertight and done right. Also if your stringers are rotted you will have to remove the whole floor.
 

micks110

Master Chief Petty Officer
Joined
Sep 14, 2009
Messages
879
Re: transom and floor replacement

Skibum- I just went back and read your first pages in your thread. When I first started I was back and forth between you, Bob, and Arch. I know Bob is working and traveling alot but we have come a long way since a few months ago! A LONNNNNGGGGG way! We'll see if we finish by spring time- me, summer time:)
 

archbuilder

Vice Admiral
Joined
Sep 12, 2009
Messages
5,697
Re: transom and floor replacement

I was thinking the same thing the other day. It seems like I have been working on it longer than I have! I have just over 3 months before summer boating season will be here......guess I should quit reading this and start working! :D
 

micks110

Master Chief Petty Officer
Joined
Sep 14, 2009
Messages
879
Re: transom and floor replacement

Skibum- What's up? Haven't heard anything in a while. Did you decide on a design for the side of the boat? Are you planning on vinyl or paint for the side graphics?

Hope all is well and we here from you soon:)
 

SKIBUM1M

Chief Petty Officer
Joined
Jul 17, 2009
Messages
604
Re: transom and floor replacement

sorry it has been so long. I have been working on the house lately. I got a new 50"plasma so wanted to make the living room look better. I repaired alot of screwholes and other defects in the drywall, repainted, then built window and door casings. The new wall mount will be here today. I have not really made any decisions on the graphix for the boat. I am still trying to put together things for reupholstery.
 

BobsGlasstream

Commander
Joined
Sep 11, 2009
Messages
2,128
Re: transom and floor replacement

Now, why didn't I think of that, Mount an satellite dish on the light pole and sell tickets at night on the lake like a drive-in theater. :p
Bob
 

micks110

Master Chief Petty Officer
Joined
Sep 14, 2009
Messages
879
Re: transom and floor replacement

I bet the 50" is going in the floor covered in plexi:D

That would be sweet!
 

SKIBUM1M

Chief Petty Officer
Joined
Jul 17, 2009
Messages
604
Re: transom and floor replacement

Hmmm there is an idea. But the tv is very heavy and i dont want it to slow the boat down so I guess I will have to leave it hanging in my living room. By the way I got a blue ray player today and it is great. Especially with 7.1 surround. I dont know If I will ever be able to pry myself away from it to go finish the boat.
 

micks110

Master Chief Petty Officer
Joined
Sep 14, 2009
Messages
879
Re: transom and floor replacement

Hey, common now! I thought we all have a date this summer once we wrap things up on the boats:D Stay focused man!!!
 

BobsGlasstream

Commander
Joined
Sep 11, 2009
Messages
2,128
Re: transom and floor replacement

Nothing with ever replace the sight and sound of the clear water and pretty girls. :p
Bob
 

SKIBUM1M

Chief Petty Officer
Joined
Jul 17, 2009
Messages
604
Re: transom and floor replacement

ok ok i will order the vinyl today. Still no luck on seats but looking. I have the boat outside under a cover and the garage is setup as a woodshop from the moldings. (Crown molding router bits save a fortune) So I guess I can start pulling staples and buy a sheet of plywood to start the upholstery. I know I can do all the side panels by simply stapeling the vinyl on but I will have to see if the sewing machine can penetrate the vinyl to do the seats.
Here are a couple of pics of what I have been up to:
DSC00617.jpg

A door and window casing
DSC00618.jpg

another door casing and the new 50" plasma
 

archbuilder

Vice Admiral
Joined
Sep 12, 2009
Messages
5,697
Re: transom and floor replacement

The door casings look really good Skibum! I can't wait to see the interior go in the boat!
 

BobsGlasstream

Commander
Joined
Sep 11, 2009
Messages
2,128
Re: transom and floor replacement

SKIBUM1M,
The woodwork does look good and the dog really looks comfy too. The TV looks pretty nice too.
Bob
 

SKIBUM1M

Chief Petty Officer
Joined
Jul 17, 2009
Messages
604
Re: transom and floor replacement

the vinyl is on its way. in about a week I will be making the inside pretty
 

micks110

Master Chief Petty Officer
Joined
Sep 14, 2009
Messages
879
Re: transom and floor replacement

Nice work on the trim. Can't wait to see the boat with the seats in it. So I guess the plasma isn't going in the boat:mad:
 
Top