650/X-2 newbie with a 650sx

G'day,

i have just purchased an 1993 650sx.

i am completely clueless when it comes to jet ski's having never ridden one (been on the back).
though i grew up around the water, and kneeboarded/wakeborded a few years ago
picked it up for what i believe is a fair price. but it needs lots of elbow grease.
at this stage it mostly looks to be cosmetic (needs all new pads, including chin)

Unfortunately the battery was dead, and the previous owner was selling due to ill health, (getting on in age, and physically incapable. currently having health issues - to the point of not being able to walk outside for the inspection or sale)
as such i was unable to learn how to start it. though the motor looks to be really clean with no obvious sign of oil weeping. (surprising when the hull has oil deposits. backs up his statement about it recently being worked on)

so can i please get a step by step starting guide.
(i did a search but couldn't find one)

i look forward to posting as this project goes on, (looking forward to learning about 2 strokes, as i ride motorcycles and work for a motorcycle store)
so far a pump block of plate has been ordered and a flush fitting is next
battery is out and will be tested at work tomorrow.

buying a ski without knowing of it is running.... (apart from owners word)
this is either going to be a thing of greatness or an absolute disaster.
 
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Location
Stockton
While the battery is out and if it has old fuel in tank you may want to pull the battery tray, oil tank, and fuel tank out to clean out the fuel tank, if its clean inside disregard this next part, also put some OE spark plugs in. It's not hard, 10mm bolts hold batt tray in, loosen fuel filler neck clamp to tank, pull the Philips screws that hold fuel filler neck to hull below fuel cap, lightly pry up while working the filler hose off the tank, the Philips screwed flang will only come out part way thin stop when the other hose clamp hits the opening below the hull opening, this is just to give you some room to wrk with the filler hose and get the tank out and back in. Once it's back together with a good battery, put new premium fuel mixed with two stroke oil 40 to 1 in fuel tank, used a ratio right cup, sold at your work most likely. You can leave oil injection hooked up for now just plug fitting at intake with a small vacuum cap, it's the small nipple below your carb sticking strait out towards right side of the hull. If you still have a choke and no primer plunger it will take a lot of cranking to get fuel to carb and start. I'd get an excersize bottle from big five with the built in straw, it's the kind you squeeze to make fluid flow out the bent straw, not the kind you sip like a soda drink. Put 40 to 1 mix in bottle and squirt a little in carb througt each time you try to start, be carefull if it backfires it could catch fire so I put air filter back on each time to prevent a fire. You can get it fired up this way without water hooked up but you cannot run it long 2 to 4 seconds or so without water. With the flush kit installed you start the ski then turn water on low, not to much or it will flood your engine internally with water. When your done you shut the water off first then keep running the ski for a few seconds to blow out some of the water before shutting off the engine. You may need a second person to turn the water on and off while you man the ski, don't have the water running if the engine is off. It may not idle right away so you may have to hold throtle open some to keep it running. You could also leave ski on trailer and back into lake and skip the water hose part, might be simpler.
 
Thank-you harbor

so today after work while there was still light,
i rigged up a rough flush kit (will have to order online, only able to get metric hose fittings at local hardware store - not 3/8)
changed over the spark plugs and put in the battery after a top up...

the battery wasn't fully charged so no hope of starting it, but it was making a nice noise from the starter cranking.
then the old man gets home and decides to try jump starting off the car...
well nothing. and i mean nothing no sound of cranking just a click when the starter is pressed.
the old man then try's to turn the shaft, and fails.

so now is where the fun begins.
i reckon something has fried with the extra power from the car,

he reckons its seized.
 
Location
Stockton
I've jumped plenty of skis with a car and had no problems so your old man may be right. You could pull the four engine mount bolts and stinger hose and slid the engine forward enough to decouple the pump from engine then see which is seized pump or engine
 

King Kang

Never enough tray time...
Location
Cary, NC
I've jumped plenty of skis with a car and had no problems so your old man may be right. You could pull the four engine mount bolts and stinger hose and slid the engine forward enough to decouple the pump from engine then see which is seized pump or engine

...or you can just remove both spark plugs and carefully us a big flat head screwdriver to see if you can push the pistons down and turn the crank. If you can turn the crank, then she isn't seized up. You also might need to tighten your battery connections before attempting another jump start. Personally, I wouldn't jump start from a car. Just be patient and let your battery charge, and then make sure you've got the cables bolted down firmly to the terminals. Good luck!
 
Location
Stockton
Pulling the flywheel cover and turning the crank by the flywheel bolt may help unstick the pistons if they are only slightly rusted, 4-d the cylinder first. Note: a friends son lost interest in his ski after tearing down the engine cause it did not run well. Long story short "it had a seizing midshaft bearings and pump" from sitting. So don't assume, perform isolation tests and try to pin point your problem. Hopefully your dad was trying to turn the engine by the couplers with the plugs removed, if that was the case you probably have something seizing or broken point is what and where ? Pump or engine ? So it's like you said now the fun begins. :)
 
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As an interim post.

I bought the ski for $900
y2ygyzyb.jpg

ga6a3yty.jpg

She is certainly not pretty. As you can see very rough. But from what my untrained sees. She actually is pretty straight. With not much needed to bring her up to scratch

Where I live the few I have seen advertised in okay condition are between $2000 and $2500.
So I figure I have $1000 to spend on her and be ahead.

$300 will be cosmetics (new pad covers. Hydro turf. Replica decals)
This leaves $700 for engine work. (Ebay parts from Usa, should let me do a complete rebuild of the engine for this amount)

Im hopeful this will be a worthwhile project. And allow me to learn about 2 stroke motor's (as a parts interpreter this information would help) not to mention the sense of satisfaction and enjoyment from these projects.
 
...or you can just remove both spark plugs and carefully us a big flat head screwdriver to see if you can push the pistons down and turn the crank. If you can turn the crank, then she isn't seized up. You also might need to tighten your battery connections before attempting another jump start. Personally, I wouldn't jump start from a car. Just be patient and let your battery charge, and then make sure you've got the cables bolted down firmly to the terminals. Good luck!

Hmm.
Ran that technique past the mechanics. And they were definitely against putting any force on the screw driver. However it is a way to check the piston by seeing if the screwdriver moves when turning the crank. But not recommended as it can jam if the sparkplug is on an angle

anyway,
todays progress,
started stripping off some of the parts, like the front nose cover and prepare the fuel tank for removal.
the battery is fully charged and no progress. still just a single click.
managed to find an long thin pole (big tent peg) to fit through the hole in the prop shaft. and cant turn it.
unfortunetly im limited by the tools i have.

my father took my tool kit to his work (hydraulic engineer, now an general manger) and is using it :(
so i cant do any more till i get my good tools back. (damn cheap tools here strip screws and wont undo bolts)

next step is to get the engine out to confirm if it is the engine or the pump.
as well as continue the strip down. (more crud then i thought, ill have to strip it all to get the hull clean)

on a positive note.
it appears to have already had a oil pump delete (only found this after i ordered a plate)
it also has had a primer installed, instead of a choke.
and im yet to find anything missing apart from a nut and bolt (not in the same place)
 
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Engine is disconected.



Unfortunately it looks like I have 2 issues. The engine is seized. However the prop is binding in one place. So it only spins part way around. Along with some scraping sounds.

So the next step is to get the engine out of the hull. This will require more muscle
mezuge2y.jpg
. Hopefully I should be able to get it done tomorrow.

As for the prop. Im not sure how I will tackle that. Ill wait till the engine is out to investigate further.

The costs are starting to rise...
I should be within budget as long as the bottom end doesn't need a rebuild.

P.s. any advice for disconecting the leads to the starter motor
 
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Location
Stockton
Pull the exaust elbow and stinger out if the hull then you can access the starter wires, I think I also removed the 4 engine mount bolts slid the engine forward and leaned a little towards the carb side. Pull the fuel tank too first. Open up your electricle box and disconnect the stator wires don't cut them like someone did on mine. Also pull th battery tray it has 4 Philips screws holding it in. Edit: now that think about it you might be able to remove the starter cable from the stud at your electrical box instead and remove wire & starter with the engine
 
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Project has been delayed for a week. As my cousin decided to get married and family is staying over.

So while im waiting. Im drowning the pistons in wd40. In the hope that its just seized from sitting. If it is still seized after the week. Off the head will come.
 
Problem when stopping a project is being motivated to start again.

Engine is now out. I suspect the front piston is seized as it holds the wd40 alot longer. But unfortunately its going to take longer to examine. Thanks to the previous owner. I can't get the head off from the outside as its stuck on.

So now the plan is to disassemble the bottom end. Then knock the head off through the cylinders.
 
WOW. that ski is ging to make you hate this sport. Sell it for whatever you can get and buy one that is in decent shape. unless of course you're one of those guys who enjoys build projects. I have an 88 650sx that is running fantastic, the paint is in great shape, pads are in good shape, and I cant seem to sell it for 1000. if they're going for 2500+ I should start sending you skis to sell out there. I wonder how much shipping would cost. ha ha
 
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I really lack motivation....

But the engine is finally apart and being looked at by the mechanics at work.
sedyvu5u.jpg


Initial inspection is.
Bore needs replacing (so ill go to an oversized piston)
Crankshaft is salvageable but will need bearings and seals.

Unfortunately the head is frozen to the barrel (hydraulic press at the old mans workshop didn't even budge it... Though did leave its mark in the bottom of the head)

And the top of the stator is broken where the screw that mounts it to the crankcase goes.

Apart from that the rest of it is in good condition. With no signs of salt water use


On a side note...
There big pistons for a 2 smoke....
 

Vumad

Super Hero, with a cape!
Location
St. Pete, FL
You can do the job right or you can do it twice. I would strongly encourage you do it right. This will save you money in the long run. However, realize that you will be investing more money in the ski than it is worth. It may be best to just write off you losses and move on. The old sick guy took a little bit of advantage of you, regardless of what prices are local to you.

Trying to get that motor working as is is a problem waiting to happen. While you may get by on those pistons, they are extremely likely to fail very soon after you reassemble. I would suggest you decided if you can hone and put in new pistons or bore 0.25mm over and put in new pistons.

With unknown information on the crank and the motor obviously sitting, I would suggest that you get a new crank. A SBT motor wouldn't be the best choice if you were racing high RPM with a ported motor, etc, but if you are just going to puts around and sell the thing to upgrade, a whole SBT motor may work out for you. However, SBT is taking a gamble. I'm just not sure it's worth the money to put a $400 hotrods crank in a old 650 motor. Buying used OEM may not be that great either. It may also be in your best interest to find a good condition used 750 motor. These are options you must decide on your own, but I would not run those pistons. I feel like putting that motor together is like assembling a timebomb with a short fuse but you don't know quite what you set it for.

Bench test the starter and other electronics if you can. Considering your stator is damaged, that's just further support to get a complete 750 setup.

Your prop is stuck because the pump liner is warped. It's hard to find someone to replace a pump liner for a Kawi pump. I believe SBT does it now. I had a place called Xactal Tool in the US do mine for about $300 with new bearings round trip shipping. You could buy a used pump just again realize you are buying old used parts and are looking at similar problems. Used will get you buy but I wouldn't buy a used for $200 when I got mine rebuilt for $300 just like new (and has years on it still like new). Also realize that your prop is rubbing the liner and that will likely damage the prop. You may have to get the edge refinished on the prop (if it was ran with a warped liner) but it will probably be acceptible. If you can't spin the prop to get it off, you can press the prop out from the back and then remove it from the shaft after it is out of the pump.

Obviously paint it while you have it apart. I would turf the whole tray and rails instead of buying rail pads. The stock ones suck.

The battery box is not held in with 10mm bolts. It's held in with wood screws epoxied into the hull. You may not be able to get it out, and if you do, you might have to epoxy them back in. I wouldn't remove it unless you have a need.

If it has the 28mm carb, it's going to be a dog, and you will need a 38-44mm carb. Again reason to get a 750 with electronics ready to go.

If you do the 750, you may just want to do a aftermarket 650 pipe and a drilled waterbox like the X2 guys do.

Sorry it's going the way it is for you but that ski is a losing investment. I would just take the time to redo it right or walk away.
 
Yep no question im going to spend more money than I will get back if I sell it.

That being said if I cut my losses and buy another ski then there is a chance it will be a "timebomb"

So the plan is to continue the rebuild but cut down the cosmetics.

The crank will be rebuilt at work (pulled apart, replace bearings and seals. Then re-pressed. The mechanics reckon its in good condition. And just needs the servicable parts replaced)

Im pretty set on boring it to an oversized with new pistons and rings.

The advantage i see in doing this is that I should get an "as new" engine that I know is good and should be easier to keep running. Especially with a hour meter running off the ignition leads to keep track of the rpm and service intervals.

I did think of importing a worked engine from the states. Or dropping in a 750. But there are no guarantees on the condition of these engines and I could be back to this stage in a few months. Also the 750 looks like alot more work and expense to make it fit.
 

Vumad

Super Hero, with a cape!
Location
St. Pete, FL
750 bolts right it. It can work okay with a AM 650 pipe but will never see it's true potential without a 750 pipe. Staying with the 650 sounds like a good option for you. Very cool they can rebuild the crank for you at work. Sounds like a better option because SBT is known to use cheap bearings.

I've been using a tach / timer from Hardline. So far it's worked pretty well for me.

Be sure to check which carb you have. Some 650 models came with a 28mm carb and that is not enough. Later models came with a 38mm carb which is acceptable.
 
Thread resurrection.
After chatting with some dedicated jet ski mechanics and service advisers where I worked. I sent the crank to a specialist, who rebuilt it. Along with machining a groove for an extra half clip in the crankcase to stop the bearing (and therefore crank) from moving.

Great to have it done by an expert renowned in the field. Was all done at a great trade price too. Just took a long time to get done as he is very sought after (can't complain, good work for cheap is a great compromise)

One of the biggest set backs was the head had fused to the barrels. Despite soaking it in wd40 and using a hydraulic press did nothing but damage the head.

So after palming it off to the person building my crank, he used all of his tricks. Including leaving it soaked in the press over a few days. In the end it was finally removed by drilling out the studs. And re-threading with an insert for the new studs. So glad to have his experience and machine shop. Otherwise this would have been junked.

Now I am ready for assembly.
Except the carby/exhaust manifold has been in a box outside for 2 years gathering dust... so everything will need to be cleaned as its assembled
 
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