Newbie JS440 Build up.. Started but need expert advice as to what direction!

[FC_Bryan]

I have a 1983 JS440 and a 1988 JS440 I want to make 1 good ski and one with left overs..lol.

So far I have the 88 motor in the 83 hull (better shape) since it was pulling 120psi in both cylinders. Mods are PJS exhaust, Mariner water box, westcoast ride plate, PJS intake grate. this is where I am now all the rest is still stock. I have a lot of play in my input shaft at the bulk head the bearing or seal is shot... tried swamping them but could not get the impeller off so i ordered the tool for it. Was wondering if I can buy a rebuild kit that would fix the seal/bearing or if I should just swap it out with the other skis.

I am mechanically capable so don't be afraid to go in depth in descriptions and procedures. I would like to do as many cheap to free things that i can to wake this ski up (as much as you can with a 440)

I also have a 550 pump and drive shaft would this help my ski in anyway with out a 550 motor?

Thanks in advance and I will post pics later.

 

[QJS]

You can match the bearings at any good bearing supplier, keep the 440 pump it works better than the 550 one.
Chris.

 

[FC_Bryan]

How do you take off the drive shaft coupler? Also does anyone have shop manual in PDF form or know where to get one? Looks like once I get that I can pull the front of the houseings bolts out and then have access to the bearing??

 

[FC_Bryan]

 

[crashnburn86]

440 pumps are better for top end but they take a couple seconds to load up. A 550 pump doesnt need to load up the way its designed so it will get you out faster but you will loose top end. I would say before spending money switch the pumps out and see how you like it. But you have a have a 550 impeller also it will not transfer from the 440.

 

[FC_Bryan]

I have a full 550 drive train from the motor back to the nozzle and it has a SS prop on it with a unknown pitch.. What would you say I use and does the input shaft splines match 440's?

 

[crashnburn86]

no. the driveshaft for a 550 pump is different from the 440's. You have to have the 550 drive shaft with a 550 pump and impellar. if you have all that swap them into your ski and try it. You might like it and then it will save you money and time finding parts and dealing with the bearing houseing and seals on the driveshaft. I always had problems withthem becuase 440/550 parts are so old. I threw 2 away the other day becuase the seals where bad.

 

[FC_Bryan]

Thanks for the info! I have a good shaft in the other ski I have and was going to swap them out first but it's good to know that that is a option! Do you know how to get the DS coupler off of the drive shaft? maybe I can just pull the housings off instead of everything...

 

[FC_Bryan]

How much top end speed will I lose if I run the 550 pump on the 440 motor?

 

[crashnburn86]

not sure, but its not like on a 550 i want to ride around WOT there hard to control with the small tray and no tubbies.

 

[FC_Bryan]

Good thing your here or I would think i was crazy talking to myself..lol
I was wondering if it would be like 5 mph or 15 mph...??? might be well worth the swap if its only 5mph

 

[crashnburn86]

im not positive if you would loose anymore then 5 but i would just switch them out and try. I have built 3 440/550's this year for friends and i, 2 where 650 conversion and one is a 550 pp engine with every mod possible. We ran a 440 pump in one of the 650 conversions and a 550 in the other to experiment. The 440 pump didn't move the ski barley. We also are running a 550 pump in the 550 ski and it is excellent. Im not sure how yours woudl compare with a 440 engine but its worth the swap. Youve been on here for days debating it. Swap it and ride that thing!!!!!

 

[FC_Bryan]

if there is a very small nick/dent in the pump housing wall (side facing the motor) will it hurt the performance at all?

 

[crashnburn86]

as long as its not in you wear ring your fine. did you install it yet?

 

[FC_Bryan]

The spot is on the side of the pump that faces the bulkhead and its right in the middle of the blade/prop

No, I just got my prop tool Monday and Have been busy. I have decided to take the shaft out of the other 440 that is in good shape and put it in my main ski. then my second ski I will install the 550 pump and shaft and put in the motor that has 115 compression in that ski ride it and see the difference it makes and then sell it or if I like the pump swap pumps and still sell it. I know that I wont be happy with the 440 or even a 550 powerplant so I will sell one and then sell or trade the other for a Newer and larger ski.. rather than dump a bunch of money into something that will not do what I want it to do.

 

[FC_Bryan]

OK So this weekend I swapped out a bunch of stuff on my Ski.. Ran across a few things that were out of the norm.. First in one of my ski's I found this in the exhaust?? I took it out but should i use it or will it hurt performance? What is it for air or water??


OK and these motor are both 440 but one is a 83 and one is a 88. The 83 has a Aluminum coupler one it the other has a Cast iron.. can i swap these out and if so how do I pull it (stop the crank from turning)??


Now I am thinking about swapping carbs since the 83 is tuned and the 88 is not.. Or is the 88 better in the long run? Also The ski with the 88 motor is running but when I am riding and I fall and the ski comes back around it is so flooded that it will usually stall out when I give it gas and then wont start until I start it and let it idle with no gas for a min or two.. What needs to be adjuster High or Low speed needle??

What motor would be better for a upgrade to a 550?? 83 or 88?

Now for the recap of my mods.. I put the 550 pump in and the 120psi motor with stock exhaust and a jetsports waterbox, Westcoast ride plate, and JS intake... The ski Rips hard compared to the stock 440 set up and not just at low end speeds but top end also! I get my PJS exhaust any day now so that should also help and make it sound better (sounds much better with just the waterbox upgraded..) Only problem I am having is that it cavitates at low speeds somewhat often on take offs.. any ideas of how to fix??
Thanks for all the help!

 

[Polish jet pilot]

Starting is not always a problem with carbs. Piston Port engines (440's and pp550 (pre 91) ) need to have a healthy engine to start - otherwise no gas goes up the transfers - no start. Make sure yo uhave a GOOD top end - otherwise it will NEVER work.