Super Jet Issue - Runs Great Initially, 30 min after riding does NOT start at all

[GreenLakeSki]

I picked up this superjet assuming the issue was carb related, rebuilt the carb and cleaned/inspected everything, checked out OK. Got it running just fine, but now it's having the same issue that it had before:

It starts right away, runs great, plugs look clean right when I start riding. I go ride for about 30min-1hour, it runs fine, if I kill it it starts back up just fine. However, after the ride if I let it sit for more than 10minutes it will NOT start no matter what.

I had this problem the other day, assumed it was too much oil in the pre-mix fouling the plugs, or the tune was fouling the plugs. I tried everything; cleaning plugs, adjusting low end screw, adjusting idle screw, playing w/ throttle while trying to start. Only after letting it sit for more than 2 hrs did it start and run again.

Fast forward to today, I ran all the "badly mixed" gas out, put some 40:1 gas in it with fresh plugs. Started great, idle is tuned great, drove for about 1hr. Come back and started to install a bilge pump kit, took about 1hr. Tried starting after that and had the same problem! This time I pulled the plugs immediately, looked fine. I also checked the spark, it looked somewhat weak. I will check the spark again after it's back to normal, then when it's not starting and compare them, maybe post a video up here.

I'm not idling the ski excessively when I pull in, and I also rev the ski a bit out of the water after pulling in every time.

Any thoughts? I'm thinking it's an electrical issue, stator possibly? I'll pull the stator cover off and take a look Sunday. If it's a fuel delivery issue, could it be the one-way valve? I checked that and it works fine.

 

[DAG]

You more than likely have a slight exhaust leak, when it starts to run like shait pop the hood, any smoke? Ride around w/o the hood on, does it still act up?

 

[GreenLakeSki]

Would I be able to notice anything while trying to start it? Where should I look for leaks, at the hose connections or on the hoses too?

Do the stock waterboxes ever leak? I noticed I get a fair amount of water in the hull after riding for awhile, even when I'm not hitting a lot of waves. I checked all the coolant lines while its running/idling in the water, no leaks there.

It can run fine for 1hr, then when I kill it, it will not start again. The performance doesn't degrade the more it runs, like it does NOT start misfiring or running sluggishly after awhile, just that it won't start.

 

[GreenLakeSki]

Weird, just went back down, the ski had been sitting with the lanyard in it (bad?) for about 2hrs. Tried firing it and the same thing happened, removed lanyard, waited a bit, then put it back in, and it fires right up. I took some video of it starting/stopping, and of the "healthy" spark in cylinders 1 & 2. I'll try to get a video of the "bad" spark when it has the issue again.

Good Spark #1

Good Spark #2

Starting/Idling/Stopping/Starting

I will follow the instructions here:
http://www.x-h2o.com/threads/80278-how-do-i-know-if-my-stator-is-bad

and post results tomorrow, along with hopefully video of the "weak" spark when it does not start.

 

[GreenLakeSki]

Went out and rode for about 1 1/2 hours, came back in and the same thing happened; starts/stops/runs fine within 10 minutes of riding. After ~10min, the spark starts to weaken, I noticed that the engine was quite warm when the spark went to crap. When I was out riding I was taking lots of water in/out which may have helped cool the engine and delay the spark issue, as I had no issues start/stop/run while I was out riding.

Here's a video of the "weak" spark, almost no spark at all:

I made sure the plug threads where getting a good ground to double check if that may have affected spark, spark looked the same regardless. I tested this the same way I got the "good spark" results above.

 

[joshp]

Just an ignorant guess but it sounds like engine floods w/ gas after it has been sitting over 10min. Maybe a float valve issue?

 

[GreenLakeSki]

If it's flooding with gas then why does the spark almost disappear? The plugs don't look that "wet", and I've even tried swapping plugs while it's not starting with the same "weak" spark produced.

 

[superramjet]

most likely stator, alot of them will shut off after they get hot when they start going bad.

 

[myblackz28]

i had a very similar problem. started out as dieing out after about an hour, and before i knew it it was down to about 3-4 minutes. tried replacing every electrical part in the ebox peice by piece and nothing worked i put it on the flush kit at home and noticed that after it would die, if i took out the lanyard and put it back in it would start, run for awhile and die again. kept doing this. led me to believe that the stop- start switch was bad. i took mine apart and cleaned everything with electronics cleaner then with a electronics lubricant both from radioshack. cleaned it all out and put it together and its been running great, although i havnt stayed out for more than a hour and half since then but ill see tomorrow. just a suggestion. clean or replace it. that my bet, sounds way to familier to my issue. good luck

 

[GreenLakeSki]

I'll try giving that a shot, bypassing the start-stop switch or cleaning/lubing it.

 

[waxhead]

Replace the charging coil on the stator

 

[GreenLakeSki]

Anyway to do that other than sending it to JSS? I can't find any guides on how to re-wind stators, but it seems fairly simple with the right tools/materials.

 

[SNOWMAN]

seems like the stator. thats common in these models. if it was the temp sensor, the ski would still fire up, but it would be in limp mode. check your check valve to make sure pressure isnt building up in tank
the water coming in sux, because it leads one to believe that somewhere in the hull you have a problem
or lits leaking from the midseal....check the small stuff first, stators go for bout 100 bucks on ebay
good luck brah

 

[GreenLakeSki]

The extra water coming in is from a warp and crack in the front of the hood, along with a really old hood seal I'm sure.




That actually works out kind of nice, I just put a bilge pump in and routed the hose right under that crack. It's just large enough to accommodate the hose until I get a proper bilge fitting.

Ski is running OK today, not having the issue *yet*, as I've been running fairly low throttle just doing turns not heating it up a ton. Also topped the battery off overnight, going to buy a AGM sealed battery later.

 

[GreenLakeSki]

Made some progress today, tested all the e-box stuff; stator checked fine except for lighting coil which checked to 4.2V, supposed to be 6-10V AC. All other resistances and voltages checked OK for the stator. Coil checked out OK, though I couldn't test the primary coil with my multimeter. E-box had some connectors that were "oily", cleaned those and put di-electric grease in them.

Cleaned out the water separator, it was kind of plugged up. The one-way check valve works, but it is somewhat difficult to blow pressure in the correct direction of flow.

Cleaned up the start stop switch, found this:


The rubber cap for the lanyard kill button was cracked and falling off. Re-sealed that, cleaned everything with contact cleaner and greased up. The connector in the engine bay wasn't corroded, but cleaned that too and put grease on it.

Played around with removing the start/stop connector and putting the idle to "kill", that actually fixed the problem. Pulled back in and plugged it back in, then it started killing itself and not starting again. Pulled the connector and now it runs fine (aside from not having an idle or kill switch).

So what does this mean? Start/Stop switch is bad, or is the CDI bad? Why would the start/stop switch start screwing up after it warms up or sits instead of all the time? That leads me to think it's the CDI, but idk.

I'll go through and clean all the contacts on the start/stop switch and see if that does anything.

Anyone have a 61X CDI I could swap?

 

[SNOWMAN]

dang cuz. nice work. if im not mistaken, the "start stop" switch in those models is known for messing up and makin it seem like something big.
i dont think its your cdi, more likely the switch.
nice detective work, shows people how to eliminate little things on your way to a solution
solid


i think the check valve is operational, its not supposed to be easy to force air though

 

[GreenLakeSki]

i had a very similar problem. started out as dieing out after about an hour, and before i knew it it was down to about 3-4 minutes. tried replacing every electrical part in the ebox peice by piece and nothing worked i put it on the flush kit at home and noticed that after it would die, if i took out the lanyard and put it back in it would start, run for awhile and die again. kept doing this. led me to believe that the stop- start switch was bad. i took mine apart and cleaned everything with electronics cleaner then with a electronics lubricant both from radioshack. cleaned it all out and put it together and its been running great, although i havnt stayed out for more than a hour and half since then but ill see tomorrow. just a suggestion. clean or replace it. that my bet, sounds way to familier to my issue. good luck

Can you go into detail how you cleaned it? I just opened it up and used contact cleaner on everything and then put dieelectric grease on all the electrical fittings. Did you remove the switches and sand/file the connections?

 

[Matt_E]

There is a metal disc and two posts in each of the two switches. They corrode. Clean those up and see if that helps

 

[GreenLakeSki]

Are there any connections in the e-box for those wires that corrode as well? The e-box looked sparkly clean when I opened it up:

Getting a sealed AGM battery, will try cleaning the switch some more and see what happens. The metal contacts in the b/w wire engine bay switch looked fine.

 

[myblackz28]

i didnt sand or file anything, just a simple wipe down with a paper towel though. took all the switch out and apart as far as i could go. with the lanyard part i had my brother hold the rubber back while i just sprayed the cleaner in there and then the lube and let it drip out a bit. circled in red are the screws holding in the lanyard kill thinger. also idk if you took the part that i circled in yellow off, but i did and i beleive that is where the small springs are, theres two fo them and two little metal contact pieces. idk how much shipping would be to 68669 but if you sent it here i would clean it for you. but sounds like you prolly have it under control. how did you reseal that top part of the rubber? cus that will let water in and create the short across the leads to kill the power. i also believe the stop button had something to do with it to. cus after mine would die it would do the same as if i had the lanyard in and held the stop switch while the start button. it would crank but not start. to that that all apart to. let me know if any of that made since. lol
http://www.x-h2o.com/attachment.php?attachmentid=132626&d=1282535964