Super Jet Whats the hill going on with my ski - need for help

c310

c310

Location
Near the beach
last week i was flushing my ski after the ride, connect the hose start the ski for 3min switch off. after that i disconnect the hose and start the ski agine to release the rest of the water in the pips. but when i hit the start button the motor screamed on my face with full throttle without hitting the finger, daaaam:Eyecrazy: what i have to do now, hit red switch still working, disconnect lanyard hello im here still working :eek5:, removed plug boot agine im working, at the end i removed battery screw but i got electric shock:skull2:. at the end my ski runned without water + full speed for 1/2min :frown:, cant hear any thing after that thinking what happens to my lovely boat, smoking every where ( reeds, exhaust ). after that i got the screw missed between the carps, i fixed it to the correct place start the ski agine yes yes its working well :Banane19:. prode pressure gauge 200/200 each cyl woow thats what i want. next morning i took the ski to the water ( skip from the work :bump:) running well for 1/2 min after that hitting the throttle but didnt get the correct respond its seem that two cyl working but somthing wrong going on. changed reeds gasgete, plug boots with wirs still at the same status.

what i have to doooo???
 
Waternut

Waternut

Customizing addict
Location
Macon, GA
Wow man that was really hard to follow but let me see if I got the general idea... You rode for a while and it ran well. You went to flush the ski and the engine "ran away" (max rpms and no way to shut it off) when you fired it up the last time with no water. Then you adjusted the carbs and it seemed to run well on the trailer. Compression is good but when you went to ride the ski again, it ran poorly in the water. Is that right?

If I understood you correctly, here is my theory. The runaway engine was caused by air in the lines because you were low on fuel. This isn't common but it can happen on a good engine with everything working right. A runaway engine is caused by a lean condition. The lean condition causes the spark plugs to glow red which continues igniting the fuel without a spark. This is why you couldn't shut it off using any standard method. The engine shut itself off when the last bit of fuel was burned off. The best way to shut off a runaway engine is to pull the throttle. This puts extra fuel into the cylinder cooling the plugs and the engine will die. The lean condition could be all sorts of things so you should never jump to conclusions to fix it. Lastly, I believe your engine was running poorly on the next ride because you messed with the carbs because you thought they were wrong and screwed up your tuning.
 
Waternut

Waternut

Customizing addict
Location
Macon, GA
Dieseling is when you shut the engine down from a normal idle but it keeps coughing or sputtering for a few seconds at very low rpms. If the rpms shoot to the moon, it's a runaway.
 
c310

c310

Location
Near the beach
Waternut said:
Wow man that was really hard to follow but let me see if I got the general idea... You rode for a while and it ran well. You went to flush the ski and the engine "ran away" (max rpms and no way to shut it off) when you fired it up the last time with no water. Then you adjusted the carbs and it seemed to run well on the trailer. Compression is good but when you went to ride the ski again, it ran poorly in the water. Is that right?

If I understood you correctly, here is my theory. The runaway engine was caused by air in the lines because you were low on fuel. This isn't common but it can happen on a good engine with everything working right. A runaway engine is caused by a lean condition. The lean condition causes the spark plugs to glow red which continues igniting the fuel without a spark. This is why you couldn't shut it off using any standard method. The engine shut itself off when the last bit of fuel was burned off. The best way to shut off a runaway engine is to pull the throttle. This puts extra fuel into the cylinder cooling the plugs and the engine will die. The lean condition could be all sorts of things so you should never jump to conclusions to fix it. Lastly, I believe your engine was running poorly on the next ride because you messed with the carbs because you thought they were wrong and screwed up your tuning.
Click to expand...

Thanks man yes that exactly what happens to me, I adjust the carbs (tuning) today and I have same problem could you advise what I should to do?
 
Cliff

Cliff

Location
Hokesbluff,al
the easy way to check for an air leak is to crank the ski and spray soapy water all over the motor. you will know it when you find the leak. could be air in the fuel line, loose intake, exhaust bolts or a gasket may have let go somewhere. the proper way to check it is to pressure test it.
 
Waternut

Waternut

Customizing addict
Location
Macon, GA
c310 said:
Thanks man yes that exactly what happens to me, I adjust the carbs (tuning) today and I have same problem could you advise what I should to do?
Click to expand...

So you adjusted the carbs back to where they were originally and it still runs bad? You might have burned up the spark plugs. Replace those and see how it runs.
 
c310

c310

Location
Near the beach
Cliff said:
the easy way to check for an air leak is to crank the ski and spray soapy water all over the motor. you will know it when you find the leak. could be air in the fuel line, loose intake, exhaust bolts or a gasket may have let go somewhere. the proper way to check it is to pressure test it.
Click to expand...
that's also good opinion I'll do it.
 
engineman44

engineman44

Location
panama city beach FL
oh man i had the same thing happen on my xp i was so upset luckily shut the gas off and i died but if it happens again the only way to stop it is choke it out it or kill the fuel the plugs turn into glow plugs beacues they get so hot just like a rc car moto have heard that u can try to flood it but when my motor was scramin full throttle i dont think prime would of helped(dosent have one either) and my neighbors were probally just as puzzled as i was haha after that it always idles high pulled carbs of and everything no leaks from intake so im assuming its my crank seal allowing air to come in but wating till i get the sj back together to pull the motor out of it
 
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c310

c310

Location
Near the beach
engineman44 said:
oh man i had the same thing happen on my xp i was so upset luckily shut the gas off and i died but if it happens again the only way to stop it is choke it out it or kill the fuel the plugs turn into glow plugs beacues they get so hot just like a rc car moto have heard that u can try to flood it but when my motor was scramin full throttle i dont think prime would of helped(dosent have one either) and my neighbors were probally just as puzzled as i was haha after that it always idles high pulled carbs of and everything no leaks from intake so im assuming its my crank seal allowing air to come in but wating till i get the sj back together to pull the motor out of it
Click to expand...

looooooool the funny thing in your storey is i have like your SJ black like the one at your Display picture. i have checked all the seals. today i done carb test and i found that leakg in one of them i fixed the leakeg and ill try the sky 2moro..
 
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