300/440/550 650sx problem

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standupguy3

Location
N/A
I have a 89 650sx that was running great until this afternoon. I ran over a reed and it sucked it up and it shut off right then. So i got off pulled the reed out and it ran fine for a second. Then after that it would run fine then bog down and die. It wouldn't start for a while then it turnover a few times a then barely start going then it start going pretty fast almost top speed for probably 3 or 4 seconds then die, and i did that the whole way home. What i was thinking is that there is a clog in the fuel line and when you let it sit for a minute it would slowly drip and fill up the carburetor bowl and then run on that and die once it was out.

Anyone else think this could be the problem, or something different? Is there any relation to the problem now and the reed that got caught in the impeller?

If there is a clog in the fuel line should i just take out the lines a blow them out and thats it?

Thanks for any help.
 
Pro-pulsion

Pro-pulsion

Location
Ontario, Canada
My ski is kinda doing the same thing. I can get sometimes an hour or so of full throttle and fun, then it starts to fade out and continually shuts down like someone hit the kill switch. I put a newer, bigger carb on it and it still did it. My next thought is to change the crank seals. The carb doesn't have a float bowl on it, so it won't fill up. The only other thought I have which may be the case for you is the impulse line coming from the engine base and wraps around to the carb. If it is rotten then you will be losing impulse vacuum from the engine to the carb and it won't draw fuel, again this was not the case for my ski as I replaced that too. My last ditch effort if all else fails will have to be replace all engine gaskets and most likely the electrical such as CDI and coil. Hopefully yours is one of the simpler and cheaper issues. One last thought too is that it's possible that you have sheared the flywheel key partially. You can pop the flywheel off and check to make sure the key is in good condition. If it is sheared it will make the ski run like crap, barely run, or not run at all.
 
B

Bren

Location
Australia
start simple fella's, same exact thing happened on my 750, turned out to be where the start stop switch wire's join into the electrical box. the (waterproof) connections had got water in them and were shorting out. like i was hitting the stop button as soon as the ski kicked over.
 
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standupguy3

Location
N/A
Bren, whatd you do to fix it? And looking at my ski, is the electrical box on the back end like where the gas gauge is but lower and on the inside?
 
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standupguy3

Location
N/A
I just went out and messed with it, it would fire fine and a few times it started up but as soon as i let off the start it would die. Most of the time though i would hold the start and it fire off every time or two but never really start, it'd fire and shake the engine but no start.

Bren, where the wires join the box, they are uncovered, the wires arent exposing but the stuff around the wires is.

Any thoughts?
 
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standupguy3

Location
N/A
Went out and messed with it some more, and it starts now. But it runs like crap and is spewing some oil out of the exhaust, and whenever you let the throttle off for more than like half a second it dies immediately. It doesnt bog down, it shuts off real quick.
 
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standupguy3

Location
N/A
I just went out and took the top off and the pistons looked ok. I turned it over and it turned over fine. But the back piston wasn't getting anything to it, when i turned it over alot the front piston was getting gas and oil and blowing it out of the top, but the back piston stayed dry.

How can you tell if the piston is seizing?
 
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standupguy3

Location
N/A
Honestly, I don't even know how to get to the reeds. Are they in the intake from the carb to the bottom of the pistons? What do i look for to see if they're bad? Cracks or chips?
 
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standupguy3

Location
N/A
Yea figured that out about 2 mins after that post, but yea i took the carb off, took the intake and reeds off (they looked perfect btw) ,but when i took the intake off i noticed that the oil pump line wasnt hooked up to the oil pump. So put it back on and put the rest of the stuff back on and fired up and ran fine. Only problem was me being stupid the whole time and not noticing it had come off.

Thanks for the help.
 
vitalikol

vitalikol

Jetski-Snowboard
Location
Pennington,NJ
You want best advise ? Get reed of oil injection and run premix. Just buy oil pump block off kit( like $10) and cup off small oil injection nozzle on intake manifold. Becouse if oil pump go bad , or line unhook or ... your engine will go . Everybody here run premix.
 
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