Js440 to 701 w/ 144 pump

[Superjetter_95]

So just got started on my next project. We've been wanting to do this for a while now but just got this thing rollin' at last. gonna be a slow project but i think in the end this thing will be awesome.

Spent most of this afternoon cleaning up the old hull, getting it ready to be worked with.

plans are so far to:
-install yamaha 144mm pump
-701 motor
-tubbies
-footholds
-refoam
-reinforce like crazy

im sure a lot more will come up as the build goes on, but thats it for now.

Got the pump to atleast sit flush with the pump tunnel today, got to see how much has to be done to make it fit.

ill keep everyone up to date as the build progresses.

Enjoy! :biggrin:

 

[MADMAT]

Man that pump looks monstrous in there! Very cool and unique build! Its gonna rip!

 

[Superjetter_95]

yeah i thought it was gonna be a much tougher fit. It only needs to go down about a half an inch to be able to put a ride plate over with modifying the bottom of the hull a tad. But it sticks out the back a good 2" with a steering nozzel on it.

the only problem was the water inlet and steering cable location. the pump sits RIGHT on them so i need to cut away at the sides a bit

 

[MADMAT]

But it sticks out the back a good 2" with a steering nozzel on it.

Shoooot....thats the latest craze anyway!!

 

[Superjetter_95]

no kiddin. some of em stick WAY out there, its ridiculous. id be scared to break that thing off

 

[vitalikol]

yeah i thought it was gonna be a much tougher fit. It only needs to go down about a half an inch to be able to put a ride plate over with modifying the bottom of the hull a tad. But it sticks out the back a good 2" with a steering nozzel on it.

the only problem was the water inlet and steering cable location. the pump sits RIGHT on them so i need to cut away at the sides a bit

You gonna cut tray area open anyway, then you can relocate water inlet and steering cable.

 

[Superjetter_95]

yep thats the plan, im cutting up the sides and the tray to get access to the lines so i can move them.

other than that, it seems the pump should be fairly easy to fit in there. it doest need to be moved around too much to fit in

 

[Foximus]

My steering nozzle with trim sits almost 4 inches behind the ski.

Early build pic...

 

[Superjetter_95]

wow, thats a ways back behind the ski. Mine with the yamaha trim nozzle isnt that far out. did having it sit back that far make it handle any different?

 

[Superjetter_95]

so heres the basics of what im plannin on doing with the pump cavity and tunnel. Ive only got to move the pump slightly up into the tray to get it to fit right. probably gonna work on getting it to fit this weekend.

hoping this will all work out :fingersx:

The red on the second picture is where the pump was before moving it down in the image

 

[MADMAT]

FWIW its is also OK to have the high spot on the pump poke through a hole on the ride plate. Mine does and I have zero issues with it and can not "feel" it at all...

 

[Superjetter_95]

thats definitely something useful to know. we may have to have the rideplate sit slightly lower than the rest of the bottom, because if not the tray would have to be raised a good 2 inches and the driveshaft would be more difficult to line up as well.

Knowing that we can have it stick through should help with not having it stick so far down.

 

[Foximus]

wow, thats a ways back behind the ski. Mine with the yamaha trim nozzle isnt that far out. did having it sit back that far make it handle any different?

Hell yea.

The ski is super twitchy and Awesome!

 

[Flash-FX]

Make and add a "bubble" to the ride plate for clearance, it won't effect handling.:smoker:

 

[Idok]

FWIW its is also OK to have the high spot on the pump poke through a hole on the ride plate. Mine does and I have zero issues with it and can not "feel" it at all...

awww......


add a couple of ribs running down the sides to space the rideplate down.......

thats a WDK thing...I dont know what rideplate the envy uses..but the rev uses a SJ rideplate with 1/8" shaved off either side...then it needs to be spaced down about 1/4"

 

[WFO Speedracer]

If the rideplate sits lower than the bottom of the ski will that not act as a brake,I am just saying.If you have some composite experience flip one of the superjet hulls upside down and remove the pump.pva the pump tunnel and pull a mold off of it,then cut out the JS tunnel,lay the mold in there and start glassing .

 

[orangefinger]

could you just cut out the whole part from an SN and fit that it ?

 

[Superjetter_95]

started the cutting today. The pump cavity is now MASSIVE compared to the stock. a stock Sn Sj has a 9.5 inch across. this has 11.25 inches across.

plenty of room to mount any steering and water lines in this.

The pump still has to move down a good distance to line up correctly with the midshaft however. so my days will be filled with much more sanding and glassing to get this thing done.

Had to chop into the bottom quite a bit to get all of the connections out and such

and if the rideplate does sit down lower than the rest of the ski, im not just going to have a jagged edge there. We will make a gradual transition up to it so it will still flow easily :smashfreakB:

 

[Motorheads5]

How is the driveshaft length working out and also don't forget the pump shoe while you are doing all the mockup.

 

[Superjetter_95]

we dont have an extra pump shoe at the moment, so that will have to be mocked up later . and the driveshaft is a bit too short, by about 2 inches. so i either have to make a longer midshaft work, or i have to use a longer driveshaft. Im working on some ideas as i work on this, so im not positive what the permanent fix on the shaft will be. we may move the pump back some if there arent any different lengths that will work on it.