Project Sea Sprite

[Cougar_15]

Hi All, After doing a lot reading here on the forum I've decided to take the plunge and start a project of my own. My project boat is a 1976 Sea Sprite Cougar 15 tri-hull with a 1977 70hp Evinrude outboard. This was my first boat, I used it for a couple of seasons then it was retired to the backyard but I could never bring myself to get rid of it.

When I got the boat it had a piece of 3/4 plywood over the floor and as I suspected, the floor underneath was rotten.

I started removing the floor at it looks like there is only one stringer down the center. I'm not sure if it is structural or just there to hold up the floor...

 

[DJ]

Re: Project Sea Sprite

The sringer is structural and it does hold up the floor.

That will be a nice boat, when completed.

 

[Cougar_15]

Re: Project Sea Sprite

Here is another pic of the stringer:

There are 2 rails (for lack of a better word) down each side of the floor that I originally thought were attached to the hull but it now appears that they are part of the floor, the first pic is at the stern and the second is the end closest to the bow :

Does anyone have any idea what these would be for? I thought they were part of the structure but now I don't know what they are. I guess a better question is, would it be safe to eliminate them or will I need to glass in new ones?

 

[maxum247]

Re: Project Sea Sprite

Nice boat you have there, I'm generally not a tri hull fan, but I do like that one.
Stowage area probably carpeted over at one time, possibly there to keep the hull from twisting and flexing too much when under way serving a dual purpose, but I think I would leave them and deck around them and use them as side pocket stowage for paddles, line, etc. It appears the deck is at the correct height as best I can tell in the pictures, an overall shot of the interior will show the interior lay out better and make it easier to judge where things may have been originally.
Nice project, good luck with it!

 

[Cougar_15]

Re: Project Sea Sprite

Yeah Maxum I was thinking storage too and yes they were covered with carpet. My only concern if I leave them in place and deck around them is that I won't be able to remove all of the old deck (which appears to go under the rails). If I do leave them should I wrap new glass around the rails and through the channel on the other side? I don't have a good pic showing the entire interior, I'll need to get my ladder out I think, but these two show it a little better (I'll try to get a better shot when time permits...):

I realized this weekend that I haven't done a real through examination of the transom, I guess I should probably do that next before I get too far along. Before I started on the floor I tried the simple test of pushing down on the outboard and looking for movement. I could not see any flex at all in the transom (it just made the trailer rock). I'm thinking to try drilling a couple holes from inside to get a better idea of where things stand. I'm hoping that I won't have to replace it (although I know there's a good chance I will) because I really don't want to have to remove the top and I don't think it would be possible to do it from the inside because of the splash well...

 

[ezmobee]

Re: Project Sea Sprite

Looks like a good project. The 3 cylinder Evinrude 70 is bulletproof. Think of all the weight you'll be saving by replacing a wet, rotted, 2 layer floor with 1 new dry one! It will probably perform much better than you remember.

 

[Cougar_15]

Re: Project Sea Sprite

Thanks for the replies and suggestions, this site and it's members are really great.

I am trying to determine if I will need to replace the transom but I'm having a hard time trying to figure it out. I drilled a few holes into the transom from the inside to take a core sample but I'm not sure what the samples mean... The wood that came out with the drill bit was a medium brown and seemed like it was a little damp (I think). I'm not sure what damp or rotten wood is supposed to look like on a drill bit. If I pressed it together it would clump and it would also crumble easily. No water leaked from the holes and all 4 sample (from different parts of the transom) had the same color and consistency. I'm not sure how much help they will be but I took a few pics of the cores:

Does this look and or sound like rot has set in? Is there anything else I can try to determine for sure if the transom will need to be replaced?

If replacement is in order I have another question, if I separate the top section how do I reattach it? The aluminum extrusion is attached with rivets and none of the rivets in the bow are accessible from the inside of the hull. Here is a pic with the rubber rub rail pulled out and another showing the bow area:

The only way I can think of to reattach the top would be to use blind rivets, would this work? I'm also thinking about SeaCast but that may be to expensive for the project budget...

 

[zach103]

Re: Project Sea Sprite

it looks wet to me.. usually when you drill wood out like that it wont stick to the drill bit.. just my opinion. could be wrong

 

[ezmobee]

Re: Project Sea Sprite

I've never done it so my opinion may be worthless but.....it seems to me that once you've got the boat as stripped down as you've got it, and you're going to go to all the effort to do the stringer and floor....you may as well, pop the top and do the transom as well. You'll have all new wood, properly encapsulated and you'll be dead before you have to worry about rot again anywhere.

 

[Labman]

Re: Project Sea Sprite

Sorry, that's definitely wet wood on your drill bit. I know, as that has the same look as mine. Dry wood, would curl off of the bit, and still show signs of the wood grain. In the spots I drilled, the wet looked like that, the dry rotted came out as a powdery substance, and the good wood showed light brown/wood grain.

Looks like it needs a transom replacement, But with ALL the experts on this site, it won't be that painful.

 

[Cougar_15]

Re: Project Sea Sprite

Thanks guys, that's the conclusion I came to as well. So, I'm adding a new transom to the project list.​

Looks like it needs a transom replacement, But with ALL the experts on this site, it won't be that painful.

Labman, I totally agree. If it wasn't for the wealth of information on this site and all the members willing to offer advice and encouragement, I would never have dreamed of taking on a project like this. ​

Last night I went to the home store to get the lumber to build a motor stand using the plans from the outboard non-repair forum. Once the outboard is off, I'll start separating the top section.​

I'm still a little concerned about how to re-attach the top to the hull after the floor and transom are done. The only way I can see how to do it would be to use blind rivets, does that sound right? I've never used rivets before but from what I read blind rivets are not as strong as other types...​

 

[Cougar_15]

Re: Project Sea Sprite

I've started working on building a stand to hold the outboard once it's off the boat but I won't get to finish it until some time next week at the earliest, we're going up to the lake for the weekend. It's going to be kind of rough not having a boat though...

Anyway, once the stand is built I need to find a way to get the 223 lb. motor off the transom and onto the stand. I've read that some motors have a lifting point attached to the top of the motor that can be attached to a winch. I think this motor has one but I thought it might be a good idea to get a second opinion before I attach a winch and start cranking... I took a couple of pics of what I think is a lifting point:

Does this look like a suitable location to attach a winch too?

I'm hoping to attach a brace across 2 or 3 beams in my garage ceiling to spread the weight and then attach a winch to that, still need to find/rent/buy a winch though...

 

[Joe_the_boatman]

Re: Project Sea Sprite

Just get a "come-along" - what we down here call a cable and hooks with a winch on it. They're around $10-$15 at Harbor Freight. Used one for my jetski, exactly as you described - brace between a few joists and lift from there.

Get some chain also, in case the comealong's not long enough.

 

[ezmobee]

Re: Project Sea Sprite

Yep, that's your lifting point and I did exactly as Joey described.

 

[zach103]

Re: Project Sea Sprite

http://www.youtube.com/watch?v=lh6RkYNxiHw&feature=related

here jonesg posted this in another forum. ive watched it like 4 times already its good and it will help.. like jones said its easier to do it when you can see it being done

 

[redfury]

Re: Project Sea Sprite

More than one way to kill that bird with a stone.... if you can enlist help from a friend, you can use the trailer to your advantage to get the motor off.

Remove the bolts, and then have someone lift the front of the boat up while you and a buddy hold the engine upright. The skeg will hit the floor, the boat will drop down past the engine mount, and you and your buddy just swivel the motor on the skeg onto the engine mount you built. No hanging hundreds of pound motors by a 2x4 in your garage...installing is the reverse. Takes 3 guys to do it effectively with a boat that sized. 2 for the motor, one for the tongue. My friend did it with an old electric shift 100hp with his 2 boys.

BTW, you can reattach the cap of the boat with either blind rivets or stainless steel screws ( my glastron was screwed together with them and then the aluminum rail was attached over that with more screws ).

 

[jcsercsa]

Re: Project Sea Sprite

Hi Cougar_15, and welcome !!! really nice ride !!! I just got dome with the transom and the stringers and the beck on mine !! One thing on the side storage if you leave them in [ i did on mine ] when you put the deck back in you will have to cut it , I did on mine , had to cut it in 4 peices instead of 2 , I think if i had to do it again, I think i would cut them out and just reglass them in after!! It took more glass to do it the way i did , cause I double glassed the joints !!
Putting the top back on mine was the same as redfurys went with the screws !!
the motor I agree with redfury , and thats the way I did it , I have a 100hp merc 1962, me and my two kids got it off and put it on a saw horse I made for it !! lifting the boat was so easy !! I just held it and then all three of use lifted it !! mine is just over 3 hundred !! getting it off of the saw horse, me and my boy did it , it was a little bit ruffer , with 3 people it would have been a lot easyer!!
Ok well keep use posted on how its going and keep them pics comming !!! and again welcome !!! John

 

[Driven1]

Re: Project Sea Sprite

On popping the top, if it's riveted down all the way around, you can just drill out (or grind the heads off the old pop-rivets from the outside of the rubrail. Just replace with new rivets when you go to put it back on.

If anything is using screws to hold the top on, especially in the bow area, the job will be harder but not impossible. If there are any screws that aren't easily accessible with your hands, you may have to cut access holes from the inside of the boat to get at them.

Good Luck with your project!

 

[oops!]

Re: Project Sea Sprite

There are 2 rails (for lack of a better word) down each side of the floor that I originally thought were attached to the hull but it now appears that they are part of the floor

Does anyone have any idea what these would be for? I thought they were part of the structure

there to keep the hull from twisting and flexing !

as far as the wet wood...you caught it before it rotted.......replace it

Remove the bolts, and then have someone lift the front of the boat up while you and a buddy hold the engine upright. The skeg will hit the floor, the boat will drop down past the engine mount, and you and your buddy just swivel the motor on the skeg onto the engine mount you built. No hanging hundreds of pound motors by a 2x4 in your garage...installing is the reverse. Takes 3 guys to do it effectively with a boat that sized. 2 for the motor, one for the tongue. My friend did it with an old electric shift 100hp with his 2 boys.

BTW, you can reattach the cap of the boat with either blind rivets or stainless steel screws ( my glastron was screwed together with them and then the aluminum rail was attached over that with more screws ).

if you choose this method........make sure your toe is not UNDER the skeg........BAAA HAAA HAAA

my bud john is right about the two side hull braces

i would cut them out and just reglass them in after!!

real nice boat.....your gonna have fun......lots of work....but well worth it

cheers
oops

 

[oops!]

Re: Project Sea Sprite

btw......3/8 drill bit on the rivets......dont wreck the alum extrusion on the rub rail.......


and.....welcome to i boats