300/440/550 81' j440 whats the largest engine that fits

[plafulotter]

I have an 81' j440 that needs engine I'm looking to see what i can fit into this hull. I heard I can use a 650. what's the good word? I'm new to standups so still learning. any help would be great.

 

[vitalikol]

You can fit 650,750,or 800 Kawasaki motor in yours 440 hull, but you need on of this

http://cgi.ebay.com/ebaymotors/Kawa...Personal_Watercraft_Parts?hash=item5ad15a9ed2

 

[jetski9010]

if its still got the 440 pump your going to want to change that if you want good low end. The 550 pump is much better that and will bolt right into the 440 hull.

 

[Sanoman]

Has anyone stuck a 701 in a 440-550 hull???

 

[the WaTeRhAwK]

if its still got the 440 pump your going to want to change that if you want good low end. The 550 pump is much better that and will bolt right into the 440 hull.

where are you guys getting this crap!?!..lol the 550 pump sucks for conversion skis.

a 550 pump cannot process even close to the amount a 440 axial flow pump can, at one time.
the prop to use is a 19 static pitch(minimum 17), the pump to use is a post '86 300sx or 440 pump(same thing), and a bored nozzel. post '86 axials have a stainless steel wear ring.

the only thing a 550 pump is good for is decent propulsion with meager hp. if you try and prop a 550 pump enough to keep up with a 440 it will try to backfeed, and will cavitate like crazy. also, if you don't prop it enough the engine will burn, which the burn issue is prevalent with both pumps, although your limited as to what you can do to adjust with the 550 setup to compensate with pitch.

the ONLY reason anyone that ever actually knew what they were doing , intentionally "switched" to a 550 pump on a js conversion setup, was because the 440 pump grabs "too much" water at a time causing a torque-roll effect, and tries to twist the ski. there's a reason that happens with the 440 pump, and not so much with the 550 pump, it's because a 440 pump doesn't mess around when you put a tall prop in it and some real hp in front of it.

 

[plafulotter]

thanks for you help!!

 

[jetski9010]

I have put so good hp motors on 440 pumps before and they dont even come close to hitting down low like the 550 pumps do.

 

[jetski9010]

Has anyone stuck a 701 in a 440-550 hull???

here you go

http://www.x-h2o.com/threads/54549&highlight=stroker

 

[the WaTeRhAwK]

I have put so good hp motors on 440 pumps before and they dont even come close to hitting down low like the 550 pumps do.

that's probably because you're not propping them enough. the 440 pump puts way less of a load on the engine with the same area pitched props as a 550 in the 17 range, that's because the 550 tries to "compress" the flow before it's released. when you put a 19 static into a 440 pump, it will try and knock your balls off if you have enough hp to twist it. if you try to raise the pitch of the prop in a 550 pump enough to keep up with the 440, it will cavitate.


that's why they quit using mixed flow pumps. the only other ski besides the 550 that ever used them was the ultra 150.

 

[MADMAT]

what are the diameters of the two pumps?

 

[the WaTeRhAwK]

what are the diameters of the two pumps?

not sure the exact numbers, the 550 diameter is larger, but the flow volume is less.

 

[MADMAT]

He is a big guy....he is gonna need as much pull as possible if this is going to be worth it.

Are they both smaller than FX-1 pumps (132mm)?

 

[the WaTeRhAwK]

I'm sure they're much smaller than fx-1 pumps. if it's for a conversion ski he needs a post '86 440 or 300sx pump, and a 19 degree prop. a 14/19 solas would be perfect.

 

[MADMAT]

I don't know then Art. I would sell it as is and find a round nose or a square nose. Getting that thing to pull you out of the water is gonna be tough.

I would like to see what a 800 in a 440 hull would look like though.

 

[the WaTeRhAwK]

if he's putting an 800 in there, go with a 15/20 and a top loader grate. it will damned sure pull him out of the water, regardless.
my buddy towed a friggin pontoon boat with his setup and it was just a slightly modded 550 with a 440 pump, 17 degree prop. it wasn't all that slow of a tow either.

 

[jetski9010]

that's probably because you're not propping them enough. the 440 pump puts way less of a load on the engine with the same area pitched props as a 550 in the 17 range, that's because the 550 tries to "compress" the flow before it's released. when you put a 19 static into a 440 pump, it will try and knock your balls off if you have enough hp to twist it. if you try to raise the pitch of the prop in a 550 pump enough to keep up with the 440, it will cavitate.


that's why they quit using mixed flow pumps. the only other ski besides the 550 that ever used them was the ultra 150.

Are you talking if you put a bigger engine on a 440 pump to run a prop that high pitched? What do you think about this build http://www.x-h2o.com/threads/52547&highlight=440+build I had impros bend me a 10-16 prop for it. I am trying to get that hit off the bottom but never had it. It has the power down low and doesnt bog down but just doesnt seem like its processing enough water. What it help to put a 17 pitch prop on this setup or even higher. I wouldnt care if it even wouldnt pull the prop with enough rpms up top. Oh yea and I also just got so dual 38 sbn carbs that were taperbored from pjs for this setup.

 

[the WaTeRhAwK]

Are you talking if you put a bigger engine on a 440 pump to run a prop that high pitched? What do you think about this build http://www.x-h2o.com/threads/52547&highlight=440+build I had impros bend me a 10-16 prop for it. I am trying to get that hit off the bottom but never had it. It has the power down low and doesnt bog down but just doesnt seem like its processing enough water. What it help to put a 17 pitch prop on this setup or even higher. I wouldnt care if it even wouldnt pull the prop with enough rpms up top. Oh yea and I also just got so dual 38 sbn carbs that were taperbored from pjs for this setup.

1 minute.........

 

[the WaTeRhAwK]

that's funny that fox says the 440 pumps don't work for low end.
I have one setup with an '81 440 pump,
stainless skat 13 degree prop,
stock '82 550 motor,
single regular bn44 carb
stock head with no head gasket, sealed with 1211, making 175 lbs of compression, full-water flow shorty stainless chamber,
stock flywheel, stock timing,
split-vein mariner top loader grate.

and it will try to rip your arms out of their sockets.


I've also got a modded 550 engine sitting in a 550sx hull with a blueprinted 550sx pump. 15 skat, wetwolf cone, jetworks flow valve, kerker stainless chamber, jetinetics charging flywheel, advanced timing, 180 lbs of compression with a copper gasket.

it doesn't have anything on the low end "hit" of the 440 pump setup. not even close.

on these small engines, the object is to get the rpms up pretty good before the pump completely loads up and tries to pull the engine down.

in other words, you can get a js to "jump" out of the water with a low pitched prop, top loader grate, a little higher compression than stock, and a short chamber that will get the rpms up, but with an axial pump.
the top speed isn't gong to be that high, I mean it's "ok" at probably 42-45, but who cares.

 

[jetski9010]

that's funny that fox says the 440 pumps don't work for low end.
I have one setup with an '81 440 pump,
stainless skat 13 degree prop,
stock '82 550 motor,
single regular bn44 carb
stock head with no head gasket, sealed with 1211, making 175 lbs of compression, full-water flow shorty stainless chamber,
stock flywheel, stock timing,
split-vein mariner top loader grate.

and it will try to rip your arms out of their sockets.


I've also got a modded 550 engine sitting in a 550sx hull with a blueprinted 550sx pump. 15 skat, wetwolf cone, jetworks flow valve, kerker stainless chamber, jetinetics charging flywheel, advanced timing, 180 lbs of compression with a copper gasket.

it doesn't have anything on the low end "hit" of the 440 pump setup. not even close.

on these small engines, the object is to get the rpms up pretty good before the pump completely loads up and tries to pull the engine down.

in other words, you can get a js to "jump" out of the water with a low pitched prop, top loader grate, a little higher compression than stock, and a short chamber that will get the rpms up, but with an axial pump.
the top speed isn't gong to be that high, I mean it's "ok" at probably 42-45, but who cares.

This is how I have my set up right now. It has around 180 psi compression, westcoast pipe (not cut down has 5 rings on it), pjs top loader intake grate, and I had a straight 16 prop sent to impros and turned into a 10-16 prop so let it rev up faster. I also got the nozzle bored and cleaned up all my veins in my pump to a nice teardrop shape.
After all of this the ski has no problem gaining RPM's fast at all it is just not getting that low end hit from the pump.
On the other side my other friends 550 I helped him build has way less work into his ski then this 440 and his hits twice as hard. I am no tuning expert but just what I have noticed.

 

[firemedicmonkey]

:Banane26:Back on Topic!:Banane26:

I have an 81' j440 that needs engine I'm looking to see what i can fit into this hull. I heard I can use a 650. what's the good word? I'm new to standups so still learning. any help would be great.

History of the Ski is unknown. It was literally found in the garabage on someone's tree lawn. It is a '81 J440 complete with everything except motor and exhuast. The Pump, Drive Shaft, and Coupler are all still in it. It even has the original single carb!​

He is a big guy....he is gonna need as much pull as possible if this is going to be worth it.

6'4" 290 lbs... ​

I don't know then Art. I would sell it as is and find a round nose or a square nose. Getting that thing to pull you out of the water is gonna be tough.

I would like to see what a 800 in a 440 hull would look like though.

I believe the game plan was to build this thing for his 8 yr old to ride. I told him since it is so complete to just get a cheap arze 440 and throw in it and be done with it. The kid weighs like 50 lbs...

I told him cut it in half and mount it on the shop wall! Buy an SXR!