Starting a 1974 Tri-Hull Restoration, it's a Stryker Mark IV model. Need help with any information or an owners manual.

MikeSchinlaub

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Wow. Are you sure you want to take this on? Just getting the body and wood back in shape is probably going to run $20k easy.
 

Scott Danforth

Grumpy Vintage Moderator still playing with boats
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owners manuals for boats of that era were simply a 4-page safety brochure that stated dont swim with the motor running, had a picture of the boat and pointed to things like the pointy end and motor end, then had a list of servicing dealers.

the boat appears to have had all the useable items stripped off of it.

Hull restoration ~ $3500-$5000
Upholstery ~$1500-$2000
Missing rub rail and deck hardware ~$2000
Missing Rigging ~ $1000
Missing outboard ~$5000-10,000

about 2 years of weekends

I agree with Mike that a restoration will cost you a whole lot more money and time than if you drove to a boat dealer, bought a 10 year old boat and could be boating today. Not to mention, there is no resale value on a 52 year old tri-hull. so any money you put into it would have no return value
 

Pvaughan23

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I knew these comments would come in, and I knew what I signed up for with this boat. I plan on learning to do fiberglass, any wood I'll replace and seal myself, I've got a plan, the resources, and the 70HP Evinrude Hustler Outboard is next to it on the ground. Just got the stand built for it to keep it vertical and cover it. And this will be my own boat for the foreseeable future.
 

todhunter

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Well, as stated there is no manual with any useful info for the rebuild. Make Scott eat crow and finish the project, and post lots of pics here. He's not far off on pricing and timing, though. It looks really rough with huge patches of missing gelcoat, so you're going to have your work cut out for you if you do it all correctly. As someone who spent 18 months and several hundred hours on a boat resto, I wish you luck and the passion to finish.
 

redneck joe

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I knew these comments would come in, and I knew what I signed up for with this boat. I plan on learning to do fiberglass, any wood I'll replace and seal myself, I've got a plan, the resources, and the 70HP Evinrude Hustler Outboard is next to it on the ground. Just got the stand built for it to keep it vertical and cover it. And this will be my own boat for the foreseeable future.
If yer in, yer in.

Enjoy the journey.
 

redneck joe

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I'll take exception to one line item cost that Scott laid out, age appropriate working outboards can be had for less that $2000 at least around here. I'm still able to get most parts for my 82 merc 50. Picked up an 87 merc 70 recently for $400 and while not had it running, compression is good and very confident i know the steps to get it running for minimal dollars. Couple years ago bought and old rotten boat with a great 84 evinrude 70 for $1200. Cost me $21 to scrap the boat, sold the trailer for $200 so net less than a grand.
 

Pvaughan23

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I was told the Evinrude I have still runs, but I'm not focused on that for right now, my biggest thing this weekend is removing the cap once more, drilling the old rivets out, Re-Fiberglass the both edges that'll meet to strengthen them and then Re-drill for the new rivets and seal anything exposed on the outside as well as fixing any crack made from attempting to remove the cap the first go around. The Stringers and Transom have already been fiberglassed and resined in, so that part is done for me, I've just gotta do the electrical, getting a new ignition, flooring, which I have a solid plan for. Flex seal on the bottom touching the Stringers to add for more of a seal, then Raptor lining on top where the carpet will go and for any hatches I create I'll use an underlining Raptor spray for those. I had planned on using the pouring foam to make things a bit easier on me as one of my bosses, who's redone about 5 different Seasons Nymphs, suggested. I've got a lot of people willing to step in and help me get this done and honestly I foresee myself being on the water by next spring. And I'm determined and willing to learn all the steps I need to in order to get there. The seats and stuff I can slowly purchase over time, the only thing I'll have some difficulty getting are the batteries. I'm already ahead a few steps with having the bilge pump and new switchboard for all my lights, live well, radio and such. And if there's anything I get stumped on I'll come here for extra help
 

redneck joe

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I would be think the already done below deck stuff would be sus. And unless the fiberglass is sanded and cleaned to perfection the flex seal will not adhere and if you think it needs it that would tend to tell me the previous work is even more sus.

All that said, de capping is the best first step to see what you have.
 

Pmt133

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So my 84 was 68 working days to get on the water. That was from removal off trailer to moving under its own power. Only help I got was someone to hold my clamps when laminating the transom to the hull and getting it on/off the trailer. So it can be not as bad as people think. Though I didn't finish the upholstery in the cabin in that time period and I have a water drip from the Y pipe so the engine needs to come out again. But that was removal and rebuild of every single piece of wood in the boat. And that includes days where I just went and took measurements and left to brainstorm. That also included the time the engine spent at the machine shop and the time I spent getting it.

The biggest thing with a project like this is knowing when to take a step back. That'll save you a lot of headache. Much like my day job, the hardest part was getting there. Once I was there it was easy to mentally get in the zone and find something to do. Having the ability to work on it completely indoors helped too. Though we went through the driest 6 months on record while I was building it. Could've spent all that time boating.
 

Pvaughan23

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I have a hangar to put it in and work on it under dry/warm conditions all winter, don't have any sort of relationship to keep me distracted and from 8am to 8pm every weekend I'll be using to work on the boat. After this weekend I should have the fiberglass and flooring completely done or at least most of the way
 

Pvaughan23

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I have a hangar to put it in and work on it under dry/warm conditions all winter, don't have any sort of relationship to keep me distracted and from 8am to 8pm every weekend I'll be using to work on the boat. After this weekend I should have the fiberglass and flooring completely done or at least most of the way
Between my passion for this restoration, and the fact that I've got knowledgeable experts as my next door neighbors, I'm pretty much set for any problems that may occur and will have help getting any parts I may need. A lot of the seats will come from FB marketplace or somewhere, but I've been trying to find a brochure or manual just to see what they used to look like so I can plan out where I'll put the front decking over the bow and things of that nature. I've dealt with a lot of stress and things not going the way I'd want the last 3 years so with this boat, I've found a new motivation and have a goal to reach which is just having this boat water-ready next spring. But with the repainting and all that I'd do more research into it when I get to that part but I was originally planning to just use marine paint specifically for fiberglass. People have suggested the gel-coating but I see that as unnecessary for a boat that'll be mine for the next 50 years or whatever I get out of it
 

MikeSchinlaub

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How long ago were the stringers and transom done? If the floor is rotten, they most likely they need redone too.

You're in for a lot of grinding, get a tyvek with a hood and a full face respirator with P100 filters for dust and organic vapor filters for the resin fumes. Use the full face for glassing too, that much will burn your eyes and make it really hard to finish.

Don't use flex seal for an undercoating. You want a good epoxy bottom paint or anti fouling if you put anything on the bottom.

Leave the cap off for now, at least until you're sure you don't have to redo any of the wood. It'll make that part way easier. Just use some ratchet straps to hold the hull in the position it would be in with the cap on.
 

Pvaughan23

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I would be think the already done below deck stuff would be sus. And unless the fiberglass is sanded and cleaned to perfection the flex seal will not adhere and if you think it needs it that would tend to tell me the previous work is even more sus.

All that said, de capping is the best first step to see what you have.
So, I would've been suspicious of it, but honestly it looks great and held up this far with keeping things sealed up down there, and the guy I bought it from already specialized in doing work like that and I trust his work
 

redneck joe

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Sounds like you are gtg.

I am just about done with my aluminum restoration and I'm old, not trying to pick up any chicks, don't care what it looks like so didn't not work on the pretty but i know for sure it is way more solid now and will outlast me and then whichever boy gets it should be gtg as well.

Speaking of chicks.... we had a guy from Finland basically built his boat, great thread for a couple years then disappeared on us before the splash, came back about year and a half later to tell us he was getting married the coming weekend. Not been back since. Left us all hanging. So, no dating until complete.....
 

MikeSchinlaub

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I've dealt with a lot of stress and things not going the way I'd want the last 3 years
Yeah, I know the feeling. Pretty much every day for like 20 years or so. Just don't place too much importance on this being the thing that needs to go right. If it gets to be more than you expected, or you screw up and have to do something over, no big deal. Take a break for a bit, it'll still be there.

You can do it, it just might take a bit longer than expected. 👍
 

Pvaughan23

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I've got a full face respirator and such to do any of the fiberglass and things of that nature. But I've got a lot of plans and ideas for things I'd like to do with this boat
 

Pvaughan23

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Don't use flex seal for an undercoating. You want a good epoxy bottom paint or anti fouling if you put anything on the bottom.
I'm just coating the plywood underneath that'll be touching the stringers with flex seal, I'm thinking since it settles tacky it would create a better seal around the edging and such. The top of the plywood will have raptor Lining, then carpeting on top of that. The original floors were gone when I got it. And the listing was only 24 days old when I bought it so I can assume about a month to a year
 

Pvaughan23

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Tonight I'll be setting up the outboard on the stand I had help building, I'll post a pic of that when I'm done, then more detailed ones this weekend when I get to actually working on the boat just to see if they need touch ups
 
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