Nytro Powered Mini Jet Boat Build

[LEE337]

Probably as low as you can go I think. OR it would be damn tempting to turbo that bad boy put the aggressive one on and see high 80's mph

Found a decent deal on a 12/18 so we will start there.

Turbo yes! That would be a riot but im about tapped out for $$ on this thing for this year need to spend some on my sled coming up here. So the boat needs a sponser for that to happen.

 

[Turtle]

Sailboats typically use a small paddle wheel that is used to measure speed. Since the Yamaha speed sensor works off a spinning gear, maybe you could rig something up and actually make the speedometer work.

 

[MrSled]

Not sure, i have had it unplugged completely so i think ill start by just plugging it in.

I would definaty plug in the sensor if you have the sensor. I'm sure the error code will go away.

 

[kinger]

If there are error codes on the nytro ecu will it restrict the rpms? Yes plugging it in should show 0 all the time and probably get the error to go away.

 

[LEE337]

If there are error codes on the nytro ecu will it restrict the rpms? Yes plugging it in should show 0 all the time and probably get the error to go away.

I dont think so because it redlines when the impeller pops out the water.

Got the new 12/18 imp to try out. Maybe tonight most likely tomorrow.

I will also plug the sensor back in. I do like the flap wheel idea to make it functional.

 

[LEE337]

Gave the 12/18 imp a whirl this weekend was still only able to pull 5800. I think the final 18 is still too aggresive. So i ordered an 11/14 ugh its only money right, this is as low as i can go with this pump. If this doesnt work i will be seriously considering turbo, but i have never dove into that world yet so i will need some education if i go that route. Or i will try to re pitch one of these myself.

I also plugged the senosr back in with still the same warning. I disconnected the battery now to hopefully reset the alarm.

 

[snobill]

Awesome !!

 

[LEE337]

Got the alarm to go away.

Next issue- I am getting a vibration up around 6000 rpms with the pump in or out and the engine only connected to the mid shaft of the pump. It seems like it is comming from the stub shaft on the engine. Would this be the same like we get with our clutch rattles? Should i pull it just to check it? Or it is what it is?

 

[OVR4D]

First, great build Lee. You have skills, that's for sure. As for the vibration you're noticing, it looks like your using a lovejoy style coupler to mate the engine to the pump shaft ... correct? If so, what have you done to ensure good engine alignment with the PTO shaft and the pump shaft? Are your motor mounts adjustable? I would start by checking the alignment and making adjustments if needed.

Not sure what to say about the pitch of your impeller. That's beyond my knowledge. But I have nothing but respect for you if you think you can machine the impeller to change its pitch. I would think that you would need a 5-axis mill to do something like that!

 

[LEE337]

Thanks OVRD. I made double dure based on your comments that the engine was aligned properly after i replaced the stub shaft bearing on the engine. It was shot, which definitely added to the vibrations.

https://www.youtube.com/watch?v=cHzhNg5Usls

Here is the 1st time on a river from last weekend. Still have some hull sdjusments to do. It has a slight hook to the bottom, but all in all very staisfied with handling.

 

[OVR4D]

Great video ... love where you mounted the camera! What River is that? Looks like a lot fun. You two are a modern day version of Lewis & Clark!

 

[moab11]

Man that looks fun!!!

 

[snobill]

That would be awesome !!

 

[sxr70001]

Very nice. So when do you start taking orders?

 

[LEE337]

Thanks guys. Got the hook pressed out this weekend she planes out much nicer now.