Jetjon build

[Flightstopper]

Picked up this 1992 Seadoo XP today for $75. Suppose to of had it fire but just needed carb cleaning so we shall see. This engine is 580cc and puts out 60 HP. Turns out when they were made they were the fastest ski to date. Has twin mikuni carbs so should be able to have some fun with it.

For those interested here is the same exact motor on a 12'x36" hull. 36mph....






Was four bolts from having the carbs off when a bunch of monster bugs starting buzzing around all over the backyard. Can't see well enough what they are but could only have images of a bunch of african bee mofo's lighting my ass up. Sulking around inside right now until I can nut up and get out there.

[Duckdog]

I couldn't ever get a good read on the speed...What did he max out at? 48?

[Flightstopper]

Highest I was able to read was 36. Pretty sure I don't ever want to see 48 in my boat lol

[NuffDaddy]

That would be sketchy as hell in a little Jon. I think I would feel safer in a 1440.
Kinda a badass little rig though. It's got my wheels turning on the stuff I could do with it. Wonder how well it would push a heavy load?

[Flightstopper]

That would be sketchy as hell in a little Jon. I think I would feel safer in a 1440.
Kinda a badass little rig though. It's got my wheels turning on the stuff I could do with it. Wonder how well it would push a heavy load?

That's the size I'm holding out for or 1442. Figure pulling a tube or skier behind it could be similar to having a load in the boat. Which I've never seen one have a problem with. Might end up having to change out the impeller but I'll cross that bridge when I get there.

Got the carbs pulled off and before making it into the garage noticed the high speed needle was missing on one. Opened up the other and the pump diaphram 'float' was in backwards and both were cracked. Really hoping the cracked floats were the original culprit and someone before pulled it apart winding up with parts backwards. At this point I'm optimistic that a rebuild kit will have it fire right off.

[NuffDaddy]

That would be sketchy as hell in a little Jon. I think I would feel safer in a 1440.
Kinda a badass little rig though. It's got my wheels turning on the stuff I could do with it. Wonder how well it would push a heavy load?

That's the size I'm holding out for or 1442. Figure pulling a tube or skier behind it could be similar to having a load in the boat. Which I've never seen one have a problem with. Might end up having to change out the impeller but I'll cross that bridge when I get there.

Got the carbs pulled off and before making it into the garage noticed the high speed needle was missing on one. Opened up the other and the pump diaphram 'float' was in backwards and both were cracked. Really hoping the cracked floats were the original culprit and someone before pulled it apart winding up with parts backwards. At this point I'm optimistic that a rebuild kit will have it fire right off.

I hope it works out good.
It would be pretty sweet for running around for the bowfishing tournaments if it could plane off a pretty heavy load.

[Bufflehead]

A friend of mine has a 115 hp Yamaha jet ski motor in his 19' x 7.5' boat. It's not fast but it will run out good and is a lot better than a jet outboard.

[Flightstopper]

A friend of mine has a 115 hp Yamaha jet ski motor in his 19' x 7.5' boat. It's not fast but it will run out good and is a lot better than a jet outboard.

Know bout what speeds? That's a hell of a boat. Not real concerned with speed since we run small water.

[Bufflehead]

I'm not really sure but I would guess around 22-25. It's a homemade fiberglass over wood boat that he built for gillnetting mullets, being that wide it shoves easy.

[Flightstopper]

I'm not really sure but I would guess around 22-25. It's a homemade fiberglass over wood boat that he built for gillnetting mullets, being that wide it shoves easy.

Sounds like y'all have lots of cool rigs out there.

[jarbo03]

Those Mikuni carbs are my favorite for most of those style engines. You checked the problem areas a;ready. Typically diaphragms are the only thing that goes wrong, occasionally the floats. Polish the needles with emery cloth. That 60 should run plenty good. A friend of mine had a 60hp Yamaha on a 1672 Lowe we used to hunt out of, while not a speed demon, it ran plenty good. Anxious to see how it turns out.

[Flightstopper]

That's awesome Jerry. Figure a narrower boat will run better with that motor? I'm very anxious to get it out on the lake to put it through it's paces before I buy the boat. Found another error they made building the carb and put the clear plastic sheet in one side where not needed. Feeling pretty confident it should be up and running without too much work, hopefully.

[jarbo03]

Narrower boat will help. His boat was wide and heavy, and some years a blind on it. Should scoot a 14' good.

[FlintRiverFowler]

One of my skis went down Labor Day and I am not enthused about working on it. At least I have a looong time to get it right.

Dammit. I hit send.
Anyways what I was gonna say was that you might look into different pitch aftermarket impellers for it once you get it built bc you may be be able to find one that carries a load better. Just like changing prop pitches.

[Flightstopper]

One of my skis went down Labor Day and I am not enthused about working on it. At least I have a looong time to get it right.

Dammit. I hit send.
Anyways what I was gonna say was that you might look into different pitch aftermarket impellers for it once you get it built bc you may be be able to find one that carries a load better. Just like changing prop pitches.

Yeah I plan on that. What model ski you have? Have been reading up a lot with this one to figure it all out and this one at least is pretty simple.

[FlintRiverFowler]

One of my skis went down Labor Day and I am not enthused about working on it. At least I have a looong time to get it right.

Dammit. I hit send.
Anyways what I was gonna say was that you might look into different pitch aftermarket impellers for it once you get it built bc you may be be able to find one that carries a load better. Just like changing prop pitches.

Yeah I plan on that. What model ski you have? Have been reading up a lot with this one to figure it all out and this one at least is pretty simple.

Got a pair of 96 polaris sl750s not real fast maybe 50 mph but they spin like a top when you cut them sharp. Tons of fun. That's why I don't wana make a jet Jon out of one of them lol

[Flightstopper]

Luckily this one looks like hell but I have looked at it a couple times thinking it's a shame to cut up a perfectly good ski. Then I think about blowing past other boats pushing over gravel bars and the thought disappears.

[FlintRiverFowler]

Luckily this one looks like hell but I have looked at it a couple times thinking it's a shame to cut up a perfectly good ski. Then I think about blowing past other boats pushing over gravel bars and the thought disappears.

Here's some more rationale to cutting it up... Having one ski sucks if you don't have a lake house. Way more fun to ride with someone, and have another ski to pull you in if you break down. Cut away. I'm ready too see this project come to life. You already have a boat to drop it in?

[Flightstopper]

No boat yet but working on it. Trying to trade my old reloading press for one bit have seen plenty for $200-350. Had some been closer I might have already dropped the cash. But if I can trade for a hull and only have $100 in the ski, that includes the dual carb rebuild kit, I'll be that much further ahead.

[FlintRiverFowler]

No boat yet but working on it. Trying to trade my old reloading press for one bit have seen plenty for $200-350. Had some been closer I might have already dropped the cash. But if I can trade for a hull and only have $100 in the ski, that includes the dual carb rebuild kit, I'll be that much further ahead.

Damn boats are cheap around there.
What size you lookin to go with?

[Flightstopper]

Wide 14 to 16'. We have many lakes around here and now is the time to buy the boats never used. Not hard to find just have to find the deal I want

[Flightstopper]

If the guy will meet up this weekend I have a deal on a wide 14' even trade for an old canoe that's been used about 5 times. Don't know hull measurement but it is 67"at the gunnels. Carb kit will be here tomorrow. This may just fall together sooner than I thought.

[NuffDaddy]

If the guy will meet up this weekend I have a deal on a wide 14' even trade for an old canoe that's been used about 5 times. Don't know hull measurement but it is 67"at the gunnels. Carb kit will be here tomorrow. This may just fall together sooner than I thought.

Probably 48 at the bottom then.

[Flightstopper]

If the guy will meet up this weekend I have a deal on a wide 14' even trade for an old canoe that's been used about 5 times. Don't know hull measurement but it is 67"at the gunnels. Carb kit will be here tomorrow. This may just fall together sooner than I thought.

Probably 48 at the bottom then.

Sounds about right. Looking at the pics the sides were pretty tall. Should be perfect for this build. So far this one has been cheap enough where I'm kicking around the idea of flipping it and going bigger. Who knows, but it is killing me right now waiting on parts to get this ski running. Figure after I finally get to put it through its paces to make sure it's good it shouldn't be too hard from there.

[Flightstopper]

Hurdle #1 cleared and the biggest one to overcome in my opinion.

Re-built carbs today get it all hooked up and can't get fuel. Dig around and find out that the vent line from the tank is nowhere to be found and end up actually finding it sitting inside the oil tank. Hook it up and find out the pick-up filters are locked up solid. Fix that and she's fires up at the touch of the button.

[FlintRiverFowler]

Isn't it fun working down in that tiny engine compartment. I lose it every time I have to work on mine

[Flightstopper]

Really wasn't bad in this one.

[FlintRiverFowler]

Mine are terrible. Taking the battery in and out is the worst part of it

[Flightstopper]

Was able to easily cruise at 36mph. Supposed to run 46 but imagine the old impeller is the culprit. Needs a little tuning but ran like a top

[Duckdog]

You forgot to post the video...