any one know anything about jet skis?

Discussion in 'General' started by mike574, Dec 19, 2008.

  1. mike574

    mike574 Well-Known Member

    I'm only asking here because it seems there are people here who might be able to help me. (i know it's a motor cycleracing board but I desprate I don't have a manual yet)

    I have a 91 kawasaki 550 sx stand up jetski that I had for a long time. I bought it in 2000 rode it for a summer and it has sat since. I have a place to ride it again so I want to rebuild it. Is there a way to crank the motor without the starter? I have a battey and the starter seems to work but the pistons are not moving. I hit the starter for a second but don't want to ruin the motor if it is locked up. I have removed the head and the cylinder walls seem fine. I have sprayed carb cleaner into the cylinders and it seeps though. I do not have a manual yet is there any oil I have to add to the crank?

    Is there any tips on trying to start an old unused motor?

    Any tips anyone haswould be appreicated.
  2. Mongo

    Mongo Administrator

    sprays some wd40 in the cylinders while you can

    but yeah, you should be able to put a socket on the crank and turn it over.
  3. Ed Sorbo

    Ed Sorbo Well-Known Member

    With the plugs out you can turn the engine over by hand at the coupler between the crank and impeller shaft. There might be a cover over the coupler that you will need to remove.

    That engine is a two stroke so no oil to add to the engine but a good chance that the bearings are a little rusty, get some light oil down there somehow and work the crank back and forth. If it has rusty bearings and they break loose don’t ride to far from someone who can tow you back to shore, things will go wrong sooner or later. If the crank is stuck having it rebuilt now will cost less than later.

    HOWEVER! You said you have a battery, but is it a good battery. Sure would be a bummer if this is all just caused by a 17 year old battery that you charged long enough to make the little green test light glow. The number of times a problem has turned out to be the simple thing that was over looked is greater than the number of posts on this site by Mongo.

    Mathematically this idea can be expressed such: simple thing, over looked > Mongo posts
    Or to simplify: st,ol > Mp

    Note from a guy who had a Jet Ski in Hawaii. Keep that thing out of the salt water!

  4. mike574

    mike574 Well-Known Member

    brand new battery fully charged. I did not want to crank it b/c I fear bending / braking the rod. Could I move the impeller shaft with out removing the motor? Mongo said to put a scocket on it. I do not see any where to put a scocket on it. As of now I have the head off, carb removed, and the battery is charged. No rust on cylinder walls. I have rebuilt top ends on 2 strokes a bunch of times but never on a jet ski and I in new teritory here.

    thanks for the replys
  5. almano

    almano The crazy Hungarian

    If the engine not turning over at all that means it seized. Either the bearings on the crank or the rod. Probably not the pistons as you said it looks good. Your best bet to pull the cylinders off. If the head already off that won't be a biggie...
  6. eroge

    eroge Well-Known Member

    Not sure about your exact model, but did you make sure that there isn't a rock stuck in the impeller? Back in 95' my roomate at the time took over payments on 2 yamaha wave runners and a trailer. The guy he got them from said that one had a "seized" engine. Therefore he threw the second one in for free. I asked him if he had checked the impeller, and he said that the dealership had ruled that out. We brought them home and within 5 minutes had the rock out, Hit the starter and fired her up. Not saying that you've got the same situation, but some of the older models with the metal impellers were prone to that. Good luck:up:
  7. mike574

    mike574 Well-Known Member

    Well it does not look like the pistons are seized b/c I put a vise grip on the impeller shaft and was able to get some movment out f the pistons bit not a full rotation. Should I keep trying to move the impeller shaft? If a bearing it rusted does that mean I am going to have to pull the whole motor out any way?

    Thanks for the replys sesing the piston move was cool, but the starter still won't move the pistons trrough the whole cycle.
  8. rubberducky

    rubberducky David Rising 742

    If you take off the front cover you will have a spot to apply a socket. There is no oil in there either so it is a quick way to get access without to much work. Personally, I would yank the motor out (4 main bolts and electrical or disconnect) and clarify that it is the motor and not the shaft, jet drive etc. You can squirt some oil in through the exhaust ports. I find it easier to disconnect the manifold than try to pull the motor out with the exhaust still on. With a flash light you should be able to get a peek at the crank and such too.

    On a side note, I have my 89' 550 motor torn down bare and am willing to part with any and all of it. Frankly I plan on getting a 750sx when possible. The hull has a better feel and handle plus more power than a built 550.
  9. mike574

    mike574 Well-Known Member

    Thanks for the replys I almost have full rotation on the pistons just wonder if I should keep trying to turn the motor over. Pistons are not seized, somthing lower in the motor is causing it not to fully turn fully over.

    WERA board rocks I knew I posted to the right place PWC forum = no replys WERA = 6
    Last edited: Dec 19, 2008
  10. mike574

    mike574 Well-Known Member

    The 89 was a non red valve motor, are part's interchangable? I know about the hulls my friend had a 650 sx witch was a much better ski then my 550.
  11. automan

    automan It's all about the drive!

    Definitely seems that the crank bearings are rusted. Flood the crankcase with PB Blaster, let it sit a day, and start working the crank back-n-forth.
    When it gets free, you can decide if you want to start it or not. Having crank rebuilt is costly$$. good luck
  12. rubberducky

    rubberducky David Rising 742

    I realize this probably isnt what you want to here, but you should do a lower rebuild. At the least I would say to either remove the cylinder or split the cases to take a look at the crank and bearings. If the bearings or crank have rusted to the point of serious pitting then it will go. It is only a matter of time and it sucks getting stuck out on the lake kicking it back in. Trust me on that. If you go to you can find links to vendors who sell new and used parts. Plus there is a forum for, as they call them, "vintage skis". You can get complete crank assemblies with bearings cheaper than you can buy the parts and have them pressed together. I am not sure if the parts from my piston port motor will match your reed valve motor.

    These motors can deal with a good bit of abuse but they are not bullet proof. Just remember, lower half goes, top half gets trashed in the process. Not much to them so you will be left replacing damn near the whole thing.
  13. Keep Up

    Keep Up N 142

    No help to the thread, but I bought a 91 550 and it was a blast!
  14. weber#465

    weber#465 mud fight

    Good forum.
    I have been there several times for parts and recommendations.
  15. Ed Sorbo

    Ed Sorbo Well-Known Member

    Sorry I did not get back to you sooner, I was riding in the snow on my XR 100 all day.

    I agree with the others. You have rusty main bearings. Replace the crank. You can get it running by getting oil in there and working it back and forth like you have been doing. This may be useful just so you know it runs before you spend money on it. But if you ride it much with damaged bearings they will fail and when they do the top end will get hurt too.

    Removing the engine is easy.
    You can turn the engine over at the coupler.
    Did you check for a rock in the impeller?

  16. mike574

    mike574 Well-Known Member

    no rock in the impeller. Last time I rode it I brought it out to take a ride and it fouled a plug and did not start. brought it home flushed it out and never rode it again. Right now I am happy thet the pistons are not seized b/c the last time I rode it was in salt water (hudson river). I stoped trying to rotate the impeller b/c I sliced my arm pretty good the other night while trying to move the impeller on a hose clamp. I want to try to get it started but I know I will have to tear it apart and replace those bearings b/c i want it to be relibable. I'll wait how and order a service maual so I know what I'm dealing with. Thanks for all the help.

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