12’ Mini Jet build

iceman5689

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It’s been a interesting and challenging build. Started with gutting the 2009 Seadoo RXT. Pulled just about everything from it other then fuel tank. Most parts will concert straight over. Other then control/throttle cables.
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neilsleder

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Fun project. However they are time consuming, and costly. I understand why Jetstream doesn’t sell turn key boats. No profit margin

Yah they would be almost the same price as a full-size boat. It’s the labor that cost the most.
 

iceman5689

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Id say the fact you have to buy a Seadoo for the running gear and toss the rest. Not too many salvage title pwc kicking around
 

ABMax24

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Id say the fact you have to buy a Seadoo for the running gear and toss the rest. Not too many salvage title pwc kicking around

That's a small part of it, but I paid $8700 for my donor seadoo, that's less than half of any comparable motor/pump combo for a full sized boat.

A lot of it is the helm, grate, intake all cost almost the same as a full sized boat. My hull wasn't much cheaper either, I paid about $7k for my 13ft hull, a few months later firefish had a couple bare 16ft piranha hulls for just over $10k.
 

neilsleder

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Id say the fact you have to buy a Seadoo for the running gear and toss the rest. Not too many salvage title pwc kicking around

I would still look into the Scott 612 pump. The biggest downfall to pwc pump is the impeller being weak. But there is a lot of companies now making thicker impellers for pwc pumps.
 

ABMax24

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I would still look into the Scott 612 pump. The biggest downfall to pwc pump is the impeller being weak. But there is a lot of companies now making thicker impellers for pwc pumps.

The problem with the 612 is you need a custom driveshaft made to fit it.

Seadoo pumps are actually pretty tough assuming the intake grate has small enough openings, I've run the stock impeller for over 75hrs and it is still usable. I switched to an even lighter solas impeller with a steeper pitch to pull the RPM down a little for fuel economy. These pumps spin fast and as such nick the leading edge of the impeller easily, the key is to keep the junk out of the pump in the first place, not build a tougher impeller. I also run a plastic wear ring with the theory being I will wreck the $40 ring instead of the $400 impeller.
 

neilsleder

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The problem with the 612 is you need a custom driveshaft made to fit it.

Seadoo pumps are actually pretty tough assuming the intake grate has small enough openings, I've run the stock impeller for over 75hrs and it is still usable. I switched to an even lighter solas impeller with a steeper pitch to pull the RPM down a little for fuel economy. These pumps spin fast and as such nick the leading edge of the impeller easily, the key is to keep the junk out of the pump in the first place, not build a tougher impeller. I also run a plastic wear ring with the theory being I will wreck the $40 ring instead of the $400 impeller.

Yah the driveshaft would be a pain. But I had a Yamaha motor and pump in my old boat. Impellers were crazy weak! Good to here the sea doos are tougher.
 

ABMax24

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Yah the driveshaft would be a pain. But I had a Yamaha motor and pump in my old boat. Impellers were crazy weak! Good to here the sea doos are tougher.

A big part of it is in how you drive it too, being light and over-powered I'm afforded the luxury of speeding up before hitting shallow spots and pulling back on the RPM's while crossing them. Impact energy increases by a factor of 4 with a doubling in velocity, if I can pull back the rpm's to 3000 from 6000 when sucking stuff into the pump the pebbles hit the impeller with 1/4 the energy, this makes a tremendous difference on impeller wear. Now heavier boats with less power may not have this luxury as they need to keep the power on to get across.
 

ABMax24

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One thing you might want to look into is the length of that seadoo drive shaft, I used an RXP donor, but IIRC the RXP shaft is 2" shorter than the RXT shaft you have, would give a little bit more interior room but of course moves the weight back.

EDIT: disregard the above, the RXT shaft is the shorter one.
 
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NoBrakes!

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I don't like the mechanical seal setup on the doo pump. ive seen them leak after a big rock hit and the bottom bends up messing with the driveshaft angle. the splined shaft is tiny too.
 
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