Sea Rayder: Can I convert Ultra 150 motor in it?

[skoolball23]

I have found a Sea Rayder jet boat for sale for cheap w/ no motor. I happen to have an Ultra 150 motor laying around. Can I do it and how hard would it be to convert it in this boat? Can the stock pump hold this power and what will I have to do to get the driveshaft to hook up?

 

[buckeye_paul]

Those ski motors rev a lot higher. I don't think the pump was designed for that. Besides, you would have to reinvent the wheel to mate them together.

 

[Dr Honda]

Anything is possible.

I don't know if I would go as far as saying, you would have to re-invent the wheel to make it work... but nothing will "Bolt up". You will have to make adapters to fit the shaft, the mounts, and exhaust. Also... none of the electronics are compatible, so you will have to get creative with that too.

It's true that the ski engines are meant to rev higher... but the Merc racing guys spin lower ends upward of 10K... so a little more RPM shouldn't be an issue. BUT... what can be an issue is the impeller. The Merc impellers are CRAZY steep!!! (39 degrees) They were meant for the torque of a 2.5 or 3 liter engine.


With that said... I was seriously considering a 260 HP Rotax 4-tec conversion for my islandia. I may still do it if I find a good donor ski.

 

[buckeye_paul]

Agreed. However, not all of us own a machine shop