The Waternut Stunt hull build

[Waternut]

I've contemplated ditching the scoop grate but I don't know on that yet. I would think that might hurt hook up considerably. I'll cut the rideplate flush with the hull tomorrow and see if that helps first.

If I can get the nose down, I think the hull will handle like a dream. I have a sneaky feeling that cruising around or high speed runs to catch a boat may be out of the question though. Time will tell for sure though...

No backflip, roll, or nose stab attempts because I'm still trying to get it riding the way I want. I also haven't installed the trim nozzle yet either. It's still sitting on downstairs the kitchen counter.

 

[chips]

yea let me know how changing the ride plate affects it because maybe i need to extend mine a little.?

 

[Big Kahuna]

The way it was nosing down so bad is from one of two things. Either the ride plate has to much positive deflection (it is sticking down farther at the rear than the front) or the pump is actually pointing down. Cutting the plate some may negate this. But I would check both of these things out.

 

[WFO Speedracer]

I actually ended up with some amount of downforce when I put the 650 pump in the 300SX,that is defiantly a possibility .On these short hulls engine placement and handlepole length is critical to get it to ride even and not nose high, much more so than on a standard length hull. I ended up with virtually the same engine placement I had with the 550 engine but I went -3 on the handlepole and added about two inches to the ride plate length with a cut down Westcoast X2 plate, I will be riding it Sunday hopefully so we will see how it goes.

 

[Waternut]

Well I chopped the rideplate flush with the back of the hull. Only the center went past the hull so the section I cut was a 3.25"x7" rectangle. Hopefully that is enough because the steering nozzle is completely exposed now.

I checked the pump orientation as BK mentioned and the pump was actually pointing a couple degrees further up than the chines on the hull. The rideplate may have a slight downward deflection but it's hard to tell.

I had another thread going about the "cavitation" problem that looks more like it was due to some grinding. You can see the intake grate was ground down by the driveshaft some. After cutting the rideplate, I also noticed that the outside of the steering nozzle was contacting the rideplate a little so I took care of that as well. I wasn't using that outer hole anyway. Hopefully between those two things, this grinding noise will disappear.

 

[chips]

yea I had to trim that part of my noxzle too. When are you going to test it out?

 

[Waternut]

Later today... It's supposed to be 75° today so there's no sense going out when it's 60°.

 

[chips]

nice. It's snowing here today. Well hopefully that'll fix your problem.

 

[McDog]

that was a big jump on the rideplate. i hope it wasn't too much!

 

[Waternut]

that was a big jump on the rideplate. i hope it wasn't too much!

The way I saw was this... A stock SJ rides "normal" and I took 3" off the back of the hull and shortened the rideplate and still liked it. This hull doesn't ride normal and the surface area I took off the rideplate is roughly equivalent to 1" off the back of the hull. I'm actually hoping that this is enough but the rideplate is composite so I can add some back if necessary.

 

[ADDict]

I would try an open grate for sure. That is a BIG scoop. I ran without an intake grate and a busted up pump shoe recently when I ripped a pump shoe out. I was amazed at how well it hooked up. I run a two bar grate anyway now though because I really like it to be loose, and they are relatively cheap.

 

[Waternut]

Here is today's video. The ride is better with the shortened rideplate but still not exactly where I want it. Before I take any more off the rideplate, I'm going to try a different turn plate and bars. That should extend the pole a couple inches. I was getting decent air off my own wake but I still can't hit a boat wake worth poo.

 

[chips]

nice. well it handles way better then mine. im going to try the shorter turnplate on mine and hopefully take a test ride on tuesday to see if the levels it out a little bit.

 

[nokfir]

your ski looks like it rides pretty good. ive been watchin all these stunt hull builds. your getting pretty high off of your own wake. are you using trim to make your setup wake? do u think its flatwater backflipp-able?

 

[Waternut]

Trim isn't hooked up on my ski yet. I think it could be a backflip hull with some nuts and some trim. You can certainly expect me to try before summer is over for sure. Can't say when I'll try though since not everything is working the way I want it to yet.

 

[ncbrock]

i think you and chips should trade steering setups!

 

[Waternut]

I've gotta say that this hull is starting to get on my nerves a bit. I can't track down this grinding issue and I can't get to anything or see anything without pulling the engine which I'm trying very hard NOT to have to do. If the hood was made even 6 inches longer, I can't see that much structural loss and everything would be SOOOO much easier to get to. I would've been able to put the limited chamber in without pulling the head pipe and exhaust manifold. I would be able to pull the gas tank without pulling the engine and I would be able to inspect the waterbox without pulling the tank and the engine.

 

[Big Kahuna]

check your couplers, they may be rubbing together. (motor pushed to far back will cause this)

 

[chad]

I was wondering ... Are you sure your aligned? the drive shaft mid bearing and motor?

can you remove your coupler cover and check the spaceing ?

if you get a bolt and a nut and sit it on top of the coupler,then snug the nut so your trying to pinch the coupler tight . then rotate the bolt around the coupler .. if your about the same distance all the way around then your good .. if not space it accordingly.


if your bendix is sticking .. try hiting your case where the bendix is while your trying to start it .. this may release it back..

its hard to pin point from the video . but thats where I would start.

Goood luck !

 

[Waternut]

Couplers have plenty of clearance...maybe a tad too much but they certainly aren't hitting. Although I despise troubleshooting, I am discovering quite a few problems that could pose serious problems later down the road. Found the two forward screws in the middle of my pole bracket were gouging the waterbox pretty good.

The problem still isn't fixed though. I'm getting really close to just cranking up the idle to eliminate the shutter/grinding problem since it seems to only happen at very low rpms.