Hi everyone,

Figured what better way to introduce myself to the forum than to start a thread for my WetJet restoration! I recently picked up a WetJet 428 for a price I could not pass up. It is in great condition and still has the original hood shield (but spray painted black). I have always loved the look of these machines and with winter approaching, thought it would be a neat project to complete in the off-season.

Luckily, the previous owner had a copy of the original service manual which has helped tremendously. I could tell the machine had some electrical issues in the past not only from the previously removed (and now missing) flywheel cover, but also there being a bookmark in the manual at the electrical troubleshooting..
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My first goal was to locate a flywheel cover in order to be able to ground all the electrical connections and stabilize the starter. A quick search on the internet lead me to a local contact that was parting out his old WetJet and passed along his flywheel cover. Here are some photos after bringing it home as well as what the engine compartment looked like. I quickly learned that I have the "difficult-to-source-parts" Cuyuna engine..

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After sourcing the flywheel cover it was time to tackle the electrical issue. Using an in-line spark tester, the lack of a spark was confirmed. Pulling out the Ohm meter and using the service manual for reference, I localized the issue to the black CDI box located behind the external coils. Thankfully I found a contact for the electronics who supplied me with a newer CDI unit. Viola! We have spark! The only issue now being the newer CDI unit no longer incorporates and connects a single yellow wire in the kill-circuit. In other words, the machine will start but the "stop" switch as well as lanyard are no longer functional. The yellow wire coming from the kill-switch circuit to the old CDI must be somewhat important
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In the meantime, my OCD kicked in and I decided to polish some of the metal components in the engine bay.. Much better!

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Here is a breakdown of what has been done since acquiring the WetJet:
  • New flywheel cover
  • New NGK spark plugs
  • New NGK spark plug boots (original boots were no longer reading any Ohms)
  • New cooling lines
  • New fuel lines
  • New fuel filter
  • Rebuilt/cleaned the carburetor
  • New CDI unit
  • Cleaned out the fuel tank

Still on my list of to-do:
  1. Identify how to incorporate a kill switch into the new CDI circuit
  2. After rebuilding the carb, there appears to be a fuel leak at the upper return choke line.
  3. Complete some fiberglass/gelcoat body work

Overall I am ecstatic about the build and have been finding ways to improve the overall performance and look of the machine. Coming across a couple WetJet threads on this forum have been super helpful as well. Once the mechanical side of things are dialed in, my goal is to focus on the body work. There is evidence of previous work done to the hull in certain areas. In addition, the bottom of the hull appears to be rather thin due to previous "beaching" of the machine.

I apologize for the long post, but figured it gives everyone a good read as to where I am currently in the build. Feel free to comment/post or offer suggestions. This is my first "true" restoration/rebuild so bear with me.

Rich
 
Looks like a really fun winter project. Always nice to see someone restore these forgotten pieces of watercraft history.

Thanks! I absolutely love the vintage water toys. Also have a couple WetBikes and Surfjets. We usually get stopped at least a couple times on the water by curious boaters.

Here are some photos of the flywheel cover I was able to get. As you can see it was in pretty rough shape. Decided to have it powder coated to not only improve the appearance, but to also protect it.

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After prep work. The pitting was pretty bad, but overall cleaned up well.

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And the final product. Decided to stick with the OEM-style flat black.

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Quinc

Buy a Superjet
Location
California
Very cool! I like the black windscreen. Here is the one I did a couple years ago. Lots of info as well as small things you can do to get more power out of her and keep her from overheating.


 
Very cool! I like the black windscreen. Here is the one I did a couple years ago. Lots of info as well as small things you can do to get more power out of her and keep her from overheating.



Thanks for posting! Your thread has been pinned to my favorites-tab ever since purchasing the WetJet. Love it!

I am debating upgrading the carburetor like you did. Any suggestions? Worth it? Surprisingly the cooling line to the exhaust chamber was already "T'ed-off" when I bought mine. I swapped all the cooling lines to be see-through as well. Any advice on where to purchase used/NOS parts?
 

Quinc

Buy a Superjet
Location
California
Thanks for posting! Your thread has been pinned to my favorites-tab ever since purchasing the WetJet. Love it!

I am debating upgrading the carburetor like you did. Any suggestions? Worth it? Surprisingly the cooling line to the exhaust chamber was already "T'ed-off" when I bought mine. I swapped all the cooling lines to be see-through as well. Any advice on where to purchase used/NOS parts?

Yes it is very much worth it. You can pick up a new mikuni 38sbn pretty cheap on ebay and amazon.

Keep posting until you get posts and I will send you a phone number.
 
Yes it is very much worth it. You can pick up a new mikuni 38sbn pretty cheap on ebay and amazon.

Keep posting until you get posts and I will send you a phone number.
Great, thanks! I will look into it - I think I found one on Amazon for $145.38? Not sure if I am allowed to post links up here.

Surprisingly I came across an OEM ski mirror on eBay that was an accessory part for the WetJet back in the day. I snagged it as soon as I saw it. Not that I plan to pull skiers, but bringing some life to the WetJet's former glory is nice. A little mag/aluminum polish and some elbow grease and looks as good as new.

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In addition, I found that the gas cap/level float was an additional accessory. This little ski has a bunch of surprises.

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I ment to say get to 10 posts. Then I can private message you.

Will do! Working on it.

Figured I would include some more close-up photos of the bodywork I have ahead of me. You can tell that at some point, someone attempted to "repair" the gel coat in certain areas. No worries - should be a relatively straightforward fix with a lot of wet sanding. There are quite a bit of spider cracks in the gel coat.

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Ideally I would strip the entire hull of its decals, patch certain areas and re-gel coat the entire hull. But, without any replacement OEM decals I hesitate to go that route. My goal is to restore it back to its OEM style and keeping a similar color scheme. If anything, I may redo the underside of the hull.
 
Sub’d! Glad to see another part of history brought back to life like Mikidymac said

Thanks for tagging along in the restoration! I am looking forward to getting the ski out on the water come spring. Once I got it running earlier this month, I was tempted to take it out on the water. Sadly, the 30 degree temperatures are too frigid for a wetsuit!

Unless the rider and the skier are under 100lbs each there is no way this thing would get a skier up! :p

Not surprised! I can't help but laugh at the old advertisements pulling a slalom skier :eek:

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@WindyCitySki. do you know which style ignition and CDI you have? By the coil I`m guessing its a nippon denso ignition? I am more familiar with the kokusan system that was used on the late cuyuna motors (like 1989 or 90 and newer), but I think I have some wiring diagrams for multiple ignition systems. Here`s the one for the kokusan Also check post 36 for a manual http://www.pwctoday.com/showthread.php?t=357962&page=4
 

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@WindyCitySki. do you know which style ignition and CDI you have? By the coil I`m guessing its a nippon denso ignition? I am more familiar with the kokusan system that was used on the late cuyuna motors (like 1989 or 90 and newer), but I think I have some wiring diagrams for multiple ignition systems. Here`s the one for the kokusan Also check post 36 for a manual http://www.pwctoday.com/showthread.php?t=357962&page=4
Yep! The Nippon Denso CDI is what I have. It has 3 connections that come off of it. A triple plug that goes to the stator, a double that goes to the external/excitatory coils and a double that goes to the kill-circuit. Here is a photo I took a couple days ago.

Thanks for the diagram!

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I believe that diagram is for the kokusan. The link that I posted is the nippondenso. IIRC the only major difference is the kokusan is grounded to run and the nippondenso is grounded to kill.
 
I believe that diagram is for the kokusan. The link that I posted is the nippondenso. IIRC the only major difference is the kokusan is grounded to run and the nippondenso is grounded to kill.

Interesting - thanks! Would the solution to my problem be simply to install a kill switch from the single red wire coming from the CDI? I have never installed a kill-switch before, but assume that it just interrupts the series circuit.
 
Page 4 of this pdf should have your diagram. The yellow/black wire should be the kill wire, it is grounded to kill the engine.

Thanks G-Body, that definitely helps me visualize things. I figured I would post a photo of the diagram. I highlighted the wires of interest. The yellow/black kill-wire is no longer present on the new CDI. Only the red/black is.

Where should a new kill wire be installed in this case? From my understanding, it is best to have it kill to the spark plugs rather than the stator? Can I wire in the existing yellow/black kill-wire directly to the red/black wire or elsewhere?

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Electrical has never been my strong point :rolleyes:
 

Moto360

Torrent Pumps
Location
Pennellville, NY
Just an observation. But those electrical components look just like the Vintage Arctic Cat snowmobile components!
 
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