300/440/550 JS 550 locked up.

[87sheerips]

Damn, well I got this ski for a deal and I really thought the kid who sold it to me was clueless and it would fire right up after I spent an hour with it. I got it all cleaned up, dumped old gas, about to clean carb, etc... When I notice the output shaft is locked up.

I didn't know you could free spin them, I thought the compression of the motor would be too much to spin by hand on that shaft. After looking at my running ski I proved my self wrong.

Anyways, the plugs look good (So catastrophic failure seems out of the picture) but this thing is locked up. I tried a strap wrench around the shaft with no luck, also tried bangin on the pistons a little with no luck

Im sure Ill have to tear her down but I wanted to see what u guys thought, if there could possibly be something else since it has been sitting outside for two years.

Thanks for any input fellas

 

[87sheerips]

Any input here guys? The previous owner says " I don't know, it just gave out on me" lol.

 

[ger87410]

U ain't gonna get ANYWHERE until you pull the head. Look at the cylinders and hopefully the case. If that doesn't tell you what's wrong, split the case. I bet the ski ate something and now the engine is an anchor.

Pull the head. It's easy. Let me know if you need the torque pattern/specs.

 

[the WaTeRhAwK]

pull the motor as a "whole" and get it out of the ski, then try to turn the impeller shaft and the coupler on the motor before you determine the engine is locked up. it might just be the prop shaft bearings. if it's a js 550, you have bearings at the front of the shaft, and bearings in the pump, also. if either of those are locked up, it won't let the engine turn as long as it's connected to it in the hull.

 

[Hfurll]

+1 on checking the schaft and prop.

 

[jetskifreak]

I would spray wd-40 down the cylinders and see if it will come loose my buddies ski was like that and it was rusted little wd-40 mite do the trick

 

[87sheerips]

Well guys, thanks for the input. Tore the motor down last night and here is the deal.

Output shaft bearings and everything past the motor seems tight and very smooth.

Top end looks good! Piston skirts, cylinder walls, domes, etc... Everything seems in good shape and can probly be slapped back together with a quick hone.

Crank is locked up! Fromt he top of the case it looks to be in good shape, but I think the bearings are rusted and shot. Looks to be quite a bit of moisture in the case so i think he stored this outside all year with water in it and now its cashed out.

I will probly be needing a crank, anyone have a used one for me?

By the way, these motors are pretty sweet. i thought a Banshee motor was simple, man I am going to be addicted to these little bastards lol!!

 

[the WaTeRhAwK]

you can pick up a good used crank fairly cheap from someone parting out their skis, but I would suggest buying a brand new one, or rebuilt one. when you buy one used you don't actually know how many hours are on it, and if you go to all the trouble to build the motor and there's only a few hours left on the crank, you're screwed. usually around $275.00 to $350.00 for a crank.

 

[ger87410]

Replace the seals while you're at it. Might save you a headache later.

 

[87sheerips]

Honestly, just for s and gigs, Ill be picking up a used crank for like $125 off ebay and re-using the pistons and everything else. Of course get a new seal and gasket kit too... But since this engine is very simple I will take the risk of getting it thru the season on a budget... I wanna see what I can cobble together here lol... Everything else seems real nice.. Carb, shaft, bearings, etc... I think it will be a nice ski. I will be re painting and making the inside of the hull mint while waiting for parts... Might as well!!

-JD

 

[87sheerips]

OK, here's what I found

Crank bearings are shot (Bought a good crank from Ebay for $125)
Stator plate is broken ( I need a stator, if any of you can help me!)

Pistons and cylinder walls look good... What is a satisfactory ring gap for proper compression? I would like to re-use the pistons and just give the cylinders a quick hone if possible.

Question: What type of puller do I need to remove the flywheel?

 

[Hfurll]

how can you tell the stator plate is broke if the flywheel is still on?

i have a plate 22.00 shipped ( just the plate, no coils) if you do need one.

 

[87sheerips]

how can you tell the stator plate is broke if the flywheel is still on?

i have a plate 22.00 shipped ( just the plate, no coils) if you do need one.

Awesome man! I will let you know asap on that!

 

[87sheerips]

Just got a pretty sweet offer.

Running complete 550 motor and a complete 650 motor that needs a crank bearing for $200! Comes with a bunch of extras and stuff... So since I bought a crank from Ebay I will have 3 motors to play with lol... Wow I cant believe how addicted I am to this stuff after like a month. This is not good. :nono:

 

[Hfurll]

while your hooked........... i have a WestCoast rideplate with the 3/4 fins and a PJS TopLoader intake for the JS hull i would part with.

 

[87sheerips]

while your hooked........... i have a WestCoast rideplate with the 3/4 fins and a PJS TopLoader intake for the JS hull i would part with.

With some pics and a description of what would be improved with these items I may consider taking them off your hands!

 

[87sheerips]

how can you tell the stator plate is broke if the flywheel is still on?

i have a plate 22.00 shipped ( just the plate, no coils) if you do need one.

Ill take it whats your paypal bud?

 

[SUPERTUNE]

When building a 550 lower end, don't buy the front seal and buy 2 of the front rear seal for use in the front! This converts the front seal to a double lip seal as the single lip seal that comes stock is lame...they leak a lot.
Buy OEM Kawasaki ONLY!

 

[Hfurll]

PM sent

 

[87sheerips]

PM sent

$$ Sent, thanks!