The battered SN restoration

Hey everyone

This will be my build and restoration thread for this old 1990 Superjet I picked up mid summer. This is my first standup, and first foray into water craft and water craft/fiberglass repair etc. I've pushed this thread off a bit until I'm pretty deep into this thing, and a build thread on anything is always fun, so come along for the ride. Big thanks to @smoofers for all his help and patience in basically guiding me on this journey, been blowing up his phone with texts about this thing and he's been awesome the whole way through, thanks again man!

Little back story, a friend of mine came to me with a pair of old JS550s he got for free for me to go through. We are both avid dirt bikers/off roaders, and living in Phoenix surrounded by lots of great lakes/water, we knew this was going to be the next obsession for the summer months. Got them running and at least somewhat water worthy to get some tray time on them over the summer, fun was had and the seed was planted; I now needed one of my own. And because I am a Yamaha fan boy, cheap, and always looking for a project, it had to be a Superjet, and one that needed work at that.

Along comes this old girl for the ripe price of $700, in pieces, mostly stock aside from the RN pole and some other odds and ends, and very tired. Lots of abuse, bad paint jobs, and questionable repairs over its 30+ year existence, fate has placed it in my hands, my goal is to return it to something of its former glory, with some improvements.

The day she followed me home
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The old 550s
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Your's truly (yes, I am perpetually pale, and live in the desert, a great combo)
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Stay tuned...
 
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So it sat for pretty much the whole summer as I had a million other things going on, with me picking at it and just getting an idea of what I had in store for me. The general plan at first was to just get it cleaned up, repaired, and running on the stock 650, to just have a good all rounder ski that I can learn the ropes on. But like all things, plans change...

As does many of my projects, this one snowballed, and I started changing my plan more and more as time went on. I've been a mechanic for 20+ years, so I have the mentality of "While I'm in there". I'm not a perfectionist or purist by any means, def more of a function over form kind of guy, if theres something on a machine that can be improved on in terms of reliability and fun factor, then I am interested.

With that being said and the parts I've accumulated for it, heres where we are at;

Repair all damage to hull, hole in front, chines chewed up, bottom scraped to hell etc etc
Reinforce bilge, pole mount, and any other weak points
De-foam and re-foam, no plans for foot holds atm as I'm dont know what my future holds in terms of freestyle, buoy chasing etc, so the tray will stay stock.
Picked up a clean 701 that will replace the basket case 650, will go through the 701 but it will remain stock as well for now.
Rad dudes SN to RN exhaust conversion system, as my water box was missing, didn't want to run the SN box, and a RN box was almost as much as the rad dudes kit.
Watercraft factory smooth hood with fuel fill
Smooth the nose a bit to make it a bit more aesthetically pleasing, was missing the stock ugly bumper anyways so why not
Already had a RN pole, might shorten it if it hasn't been already.
Paint job, will be returning to white and will run the 95 Superjet scheme (I'm a sucker for 90s teal and pink neon stuff)
Hood mod
Sponsons, hadnt planned on adding these but got a good deal on a set coming so why not
Among other things as we go

With that, I got to work. The hull had its fair share of scrapes, holes, and damage. Someone had painted it this maroon color, as well as did some sort of coating with splatter style paint in the bilge that was peeling up. So first plan was to get the hull down to as bare as I could for what needed to be repaired.

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The bilge was bad, whatever this coating was, it was coming up in sheets, getting this crap out was imperative to a proper repair, so I got after it.

Scraper and a heat gun worked best
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De-truf
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Knocking down the ribs for reinforcing
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Picked up my 61X
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At this point, I found a local soda blasting place that would strip the hull for me for 250 bucks, which I thought was well worth it at this point. Would save me the hassle of sanding all the maroon off, and get the bilge as best as it could. I realize that I still have quite a bit of body work ahead of me, but the blasters still did a great job.

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My hood piece showed up so tossed it on to see, so much better then the stock hood!
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Bilge getting better!
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One of the many holes
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So now it was time to dig into the tray. All these stories of water logged foam, figured I may as well see what's up. It was indeed wet, however not as bad as some of the ones I've seen on here, mainly around the shaft tunnel, aside from that, it was pretty dry. I was surprised it was dry where the JB weld crack repair was on the back left of the tray.

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Cut the hood liner out, pain in the ass, I def messed up and went a little deep in areas, but nothing that can't be fixed.
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Sanded down the bilge one last time to get ready for bond line filling and reinforcing.
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Now I was getting ready to finally do some glass work. I've had some experience building seat pans for motorcycles and what not, but never anything water craft related. Put in an order to US composites, and dove in.

Sad that this was almost 1k in supplies and parts :eek:
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Some shots of the damage
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Will be filling the exhaust holes to position the new pipe better
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The nose hole
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Duct tape works great as a mold/release
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Had to get creative with positioning
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First repair done, not bad!
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More repair work

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Filling the exhaust holes and old extinguisher mount (I realized later that the outer mounts were for the ebox, drilled those back out)
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layed up the outside of the nose for further strength
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Thickened epoxy to smooth the old bilge exhaust hole
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Same on the rear
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Finally began reinforcing the bilge by laying some thickened epoxy in the bond line. This took some time, as I had 4 pours I needed to do and position the ski as such to make sure it got in the bond line properly. While that was curing I started working on other things like my hood and what not.

Cut all my forms to get ready to go
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Before laying the epoxy, I beefed up the pole mount front and back, and laid some epoxy in the hood seal area as my ski had the infamous "Squarenose Sag"
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Epoxy spread into the bond line
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Filled the hood vents with thickened epoxy, as well as all the cracks and holes on it
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Waxed a piece of plywood and laid up a liner
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First part of the liner in, I wanted to keep the factory extinguisher mounts, and used them to hold the liner where I wanted it while I glassed it all in
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2nd part of liner, this wans't the original plan as I wanted it to be all one piece, but screwed up and trimmed it too far back, oh well.
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Hood liner done, have four holes for intake/water drainage at the rear of the hood, will drill holes and run intake tubes later on

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Getting the mat laid in on the sides of the bilge, filled all the old pisser/bilge holes, I will drill my own holes later
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Reinforced bilge, ready for paint
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Cut my exhaust in, I will be painting the bottom hull black, and I want my exhaust black as well, so this was part of the plan. Also sealed up the tray and bilge with 5200, went crazy with 2 bottles of it, will test here in about a week when it cures (takes 7 days according to the bottle). I will be using expanding foam in the tray so I will be making sure the tray is as sealed up as it can get. Yes I have read all the foam threads on here and how you can never really get these things sealed up, but for me its fine.

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Positioned it a bit lower for possible future foot holds, and just ease of install etc
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And with that were up to the present, I will update this thread as I go along, hope you guys enjoy!
 
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Thanks fellas!

Actually, wanted to see what you guys think, eventually I will be upgrading the motor with a B pipe and a head, I'm still a little new to all that but I think I need to run dual cooling for that setup no? Should I run a 3rd line while I have the tray open? Or should I just use the siphon line? I'm planning on running bilge pump (s) and this ski MAY see surf once or twice in its life if at all. I know it's good to keep the siphon as its pretty fail proof, but I'm also keeping the nose foam and running foam in the tray, so if I DO sink it it should still bob and not sink to the bottom of the lake I thought? May even shove some pool noodles in the bilge just to be safe
 
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smoofers

Rockin' the SQUARE!!!!
Site Supporter
Location
Granbury, TX
I'd run dual cooling using the siphon line. A bilge pump is cheap and works great with the boat sitting still or full throttle. I haven't run a siphon bilge on my SN ever and I don't miss it.
 
Thanks fellas!

Actually, wanted to see what you guys think, eventually I will be upgrading the motor with a B pipe and a head, I'm still a little new to all that but I think I need to run dual cooling for that setup no? Should I run a 3rd line while I have the tray open? Or should I just use the siphon line? I'm planning on running bilge pump (s) and this ski MAY see surf once or twice in its life if at all. I know it's good to keep the siphon as its pretty fail proof, but I'm also keeping the nose foam and running foam in the tray, so if I DO sink it it should still bob and not sink to the bottom of the lake I thought? May even shove some pool noodles in the bilge just to be safe
My square goes in 60’s on stock single cooling line and stock exhaust tube.
 
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