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Jet pump warp?

Marvin willis

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Tried to go out today and when I pulled it off the trailer it was making a lot of noise so I loaded it up and came home. I had someone crank the motor with me under it and could see sparks. So I was thinking a bad bearing. Pulled it apart and it seems warped. Not sure if it's the prop or pump. Am I imagining this? Does this happen
 

Bruce

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Is this your boat or a ski?
 

Bruce

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The pump liner (wear ring) can swell and become too small to allow the impeller to spin freely.

Is that a metal liner inside a plastic outer section?
 

Speedling

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Everything is replacable you just may need the housing as well.
Take it out and spin the blades and shaft with tge nose cone on the counter and look for warpage or unbalanced something.
Then take shaft and roll the straight part across a flat work bench to see if shaft is bent.
for the inside of liner you will need to find a way to measure it. Maybe cut a thin wood dowel rod to fit perfectly and then spin it around to find tight spots.

I don't know the construction of your line but typically sanding it down isn't a realistic option and new parts are needed.
 

Marvin willis

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I just ordered the tool to pull the impeller. What do yall think of the look of my impeller?
 

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I just ordered the tool to pull the impeller. What do yall think of the look of my impeller?
I would spend the $100 to have it reconditioned while you have it off.
 

Speedling

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Agree with @Bruce and it looks like it's not 100% centered.
 

Cobra Jet Steering LLC

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I went through Hell with ultra 250 pumps the originals had only 2 bearings and would last about 50 hours before the bearings failed , they then went to 3 bearing pumps those lasted about 150 hours and failed the factory rep said 150 hours was all that you could expect from the pumps so they refused to cover it. I used mine in salt water only, but I added several zinc anodes to the pump and ride plate. Each time the bearings went south the impeller would also get torn up. I did a play by play post on pwc weekly, http://www.pwcweekly.com/showthread.php?56068-Kawasaki-Ultra-250-is-a-piece-of-crap
may be important if you have the same issues and you purchased the extended warranty like I did.
 
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Marvin willis

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Can I order the rebuild kit for the 300 on eBay. plus a shaft and nut to upgrade mine?
 

Marvin willis

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If your "Jeff". Holly crap. Mine over heated and popped the head gasket so nationwide bought me a new $6000 motor with 2010 head. Supercharger pulley locked up last year so I upgraded that to a r&d pulley and then the tensioner pulley bearing died. Both things broke the belt 4 hrs apart so that sucked. Now I'm dealing with the pump for first time.
 

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Yes that was the worst ski I ever owned. purchased it new, You probably have the 3 bearing pump mine was the first model the ultra 250, so they were using the non supercharged 4 stroke pumps, but those crapped out fast.
The impeller gets eaten up when the pump goes as does the liner, I purchased all my parts at s b t in Clearwater www.sbtontheweb.com they didn't really understand the differences in 2 or 3 bearing pumps as the pump housings were different but they did do a good job on the impeller, I hand picked a rebuilt pump, they didn't know the supercharged pump had different water outlets but I found the correct one and it worked fine.
Needless to say I only buy Yamaha 1800 engine powered skies and I have no more desire to own a supercharged engine, keep it simple stupid.
I custom build steering for the Yamaha fx ho cruisers and I love them I even tow a super Mable tube with 3 people on it with no problem.
I can drive the Yamaha skies all over the place with my feet and standing with no hands just cruising at 55 mph and jump waves like crazy, the kawasaki was a big fat nothing on the wave jumping, it just plows through them and fills the hood compartment with water. Gets you soaked in small waves.
Best day of my boating life was when I sold or actually nearly gave that ski away. It went in for repairs on a regular basis. I even had to build a special trailer with removable tower for loading and off loading that Kawasaki from my dual trailer so I could constantly bring it to the shop for repairs, now that it is gone the trailer is sitting in the back yard with flat tires. I was talking with a guy at the beach a few days ago with a broken 260 kaw and he has the same problems he's over it also. Too bad it was so unreliable because when it ran it really it carved with the steering on it.
 
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Marvin willis

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Mine looks just like that. My tool came in today. It was the front bearing that went bad. Ordered all new 300x parts to put back in
 

Marvin willis

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Question about the nut that goes behind the rear bearing on the 300 that my 250 lacks. Is there a certain torque for it?
 
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