1980’s Superjet?

Joined
Jan 28, 2018
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341
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California
#1
So this escalated quickly.

I have my Project Boat Anchor going but I wanted to start looking for a cheap ski for my second cousin. She turns 16 in August which is when you can operate a ski in California. She already rides dirt bikes and what better way to spend time than dirt bikes and skis.

That and I can’t move forward on mine until it warms up enough to shoot paint.

So off to Craigslist....

Tuesday morning a 1991 SN pops up and I immediately called on it. We met on Wednesday at lunch. Ski was dusty and hadn’t been in the water since 2013. The guy was the second owner but was best friends with the original owner. Guess they bought 2 brand new in 1991 and painted them to match the family boat.

This explains the 1980’s paint job.


Battery was dead obviously so I brought my own as usual.
Compression was a perfect 150 each cylinder. Nice hot spark but really old stinky gas so I didn’t try to fire it.

The ski is clean and even has the original mats. The only thing missing is the yellow container under the hood and it’s all stock and never been apart. The only thing it has is a bilge pump, R&D scoop grate and Skat 9-17 impeller.

So for under $1K and a stand I loaded her up.
 
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Joined
Jan 28, 2018
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341
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California
#2
Got her home and a good bath cleaned her up.


Being a 25+ year old paint job it’s actually in pretty good shape. The battery acid did a number down the side but it be what it be.

Actually the more I see it the paint is starting to grow on me and at least it isn’t another all white SN.

So like always I can’t leave a new ski alone. I like to take any new to me ski completely apart and rebuild it back up just so there are no surprises. I like to wrench once, make sure everything is good and spend my summer riding not fixing broken skis.

Engine out? Check.


Midshaft has some slop so rebuild kit is on order. The 9/17 impeller is getting replaced by a 14/18 Super Slimline I have from the donor B1 based on Skat’s recommendation.

I wanted to check the little 650 over so it was completely torn down.

Cylinders and pistons look great and there is even still factory crosshatching. Little surface rust spots but nothing I’m going to worry about. This people is why I fog my engines after every ride.

The crank looks mint, if I didn’t know better I would say it’s brand new.

The pump and bearings look great but I’m getting rid of the funky early bilge thing.

And making it into the newer siphon style.


I sent the head to Group K to be cut for 91 octane.

The engine is going back together with OEM Gaskets and seals. I just want this to be a fun reliable loaner so nothing fancy.

Stay tuned as I wait for parts from Yamaha and Jet Maniac.
 
Joined
Jan 28, 2018
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341
Location
California
#4
Great find! To answer your thread title they did make a 1989 SJ.
Thanks.
I was just joking about the 80's because of the paint job.

Where is this 89' superjet? Everything I see says they only made the WR and WJ in 89'

Alos, are you going to the Pismo Freeride? I might actually have something to ride this year instead of just watching like and idiot.
 
Joined
Feb 19, 2013
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4,730
Location
Chico California
#5
Thanks.
I was just joking about the 80's because of the paint job.

Where is this 89' superjet? Everything I see says they only made the WR and WJ in 89'

Alos, are you going to the Pismo Freeride? I might actually have something to ride this year instead of just watching like and idiot.
My buddy @SVTPete83 has an 89 SJ. Has 89 as the last numbers in the VIN.

Bought camp passes for the freeride yesterday. Will be at the freeride! 20-24th. Make sure and say hey if you see me.
 
Joined
Jan 28, 2018
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California
#6
My buddy @SVTPete83 has an 89 SJ. Has 89 as the last numbers in the VIN.

Bought camp passes for the freeride yesterday. Will be at the freeride! 20-24th. Make sure and say hey if you see me.
Hopefully I’ll see you there and put a face to the name. Also let me know if you guys need anything since I’m only 30 minutes away. Hard to get motivated to camp in the cold when home is so close. I’ll also have tools and things like carb kits if you need emergency repairs.
 
Joined
Jan 28, 2018
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341
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California
#7
Got a little done this weekend.
New oem seals and Gaskets and Torpedo for the little 650, nothing but the best.


And a little 1184 for the cases.

Like I said earlier the crank looks mint.


All ready for cylinders and pistons.
 
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Joined
Jan 28, 2018
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California
#10
So I got a little more done this week.

The poll bushings were sloppy so I ordered new oem ones and used some JB Quick Weld as suggested here.

Also a new spring from Jet Maniac.


I got the head back from Group K for a 91 octane cut but I forgot to take a picture of it. It did look perfect as usual from Harry.

So I got it installed with a factory head gasket and put my circa 1990 Group K leak down kit to work.


Now this engine was air tight before I tore it down and now it was leaking like crazy. First leak I found was a loose spark plug. Nope, still leaking. Next was the intake manifold and it was bad. I used all oem Gaskets dry as usual so this was a surprise to me. But nothing a little 1211 couldn’t fix. So after drying over night it held 8 psi and didn’t drop a pound over 30 minutes.


So that’s about it for today.
 
Joined
Feb 24, 2014
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Los Gatos, CA
#11
I saw you noted dry intake gaskets, I thought it would be good to apply a light coat of grease on each side to help the gasket seal and get compressed into place? Wondering because I'll be installing an intake soon.

When you removed the intake were you able to tell why it wasn't sealing?
 
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#13
Don’t use grease on any gaskets, only O-rings.

If the gasket have the silicone printing they should go on dry, if they are special coated like the factory exhaust and head gaskets again dry.

All other ones can benefit from 1211.

I don’t know why it didn’t seal as every surface was prepped and clean and I typically put intake gaskets on dry.

This was a NOS kit from Yamaha so the gaskets could be a little dry from being old but like I said a coat of 1211 on all the intake surfaces fixed it.
 

Roseand

Ready to RIP
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Dec 31, 2012
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Wisconsin
#14
Don’t use grease on any gaskets, only O-rings.

If the gasket have the silicone printing they should go on dry, if they are special coated like the factory exhaust and head gaskets again dry.

All other ones can benefit from 1211.

I don’t know why it didn’t seal as every surface was prepped and clean and I typically put intake gaskets on dry.

This was a NOS kit from Yamaha so the gaskets could be a little dry from being old but like I said a coat of 1211 on all the intake surfaces fixed it.
Had the same thing happen with a 61x intake. Cleaned everything perfectly, torqued correctly etc, still leaked out of the intake mani. Always sealed intakes with sealant ever since.. Permatex high tack sealant works good too! Less of a mess to work with.
 
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Feb 24, 2014
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Los Gatos, CA
#15
Hmm ok. I have Yamabond 5 I can use on the two intake to case gaskets around the Reed cages.
The carb to intake gasket has the white silicone bead built into the gasket so that will go on dry.
 
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Jan 28, 2018
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California
#16
Hmm ok. I have Yamabond 5 I can use on the two intake to case gaskets around the Reed cages.
The carb to intake gasket has the white silicone bead built into the gasket so that will go on dry.
Pretty sure that sealant is only for metal to metal like the cases. I would get some 1211.
 
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Feb 24, 2014
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Los Gatos, CA
#17
Pretty sure that sealant is only for metal to metal like the cases. I would get some 1211.
Thanks, yes I see Yamabond 5 is full hardening.
Yamabond 4 is equivalent to threebond 1184/1194 and semi hardening.
Threebond 1211 is full hardening for metal to metal bonds.

Edit: I ordered 1211 for the gaskets.
 
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Joined
Jan 28, 2018
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341
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California
#18
Thanks, yes I see Yamabond 5 is full hardening.
Yamabond 4 is equivalent to threebond 1184/1194 and semi hardening.
Threebond 1211 is full hardening for metal to metal bonds.
I’m not sure about the 5 but 1184 is used for the cases and 1211 for everything else. I know some use 1211 for cases too though.
 
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Feb 24, 2014
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Location
Los Gatos, CA
#19
I now have a tube of 1211. I did a test application on a small section with the old gasket to see how it works. Seems like most of it squeezed out when I applied and assembled, but it did bond well. Do you let it tack up a bit first or apply and immediately assemble?

And I will apply to both sides of both gaskets for the intake manifold to case? Since there are two gaskets with a steel plate in-between.
 
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