Engine stalls and surges, water in carb?

[mlebauer]

Got a barely used 2001 Sea-Doo Challenger last year from my father who stopped using it after a few years owning it. It sat for a few years so I had the fuel system cleaned, after which it was running well. Just started using it this year. Was running well until yesterday, 3rd time out this year. It ran well for a few hours. Then the port engine stalled, but started up again and ran ok. About another hour and the starboard engine did the same thing. It wouldn't re-start. The port engine was now also not running well, surging between 4000-5500 rpm.

Limped back to the ramp like that. Before getting back I was able to get the port engine started but it wouldn't turn more than 2500 rpm. After getting back I pulled the boat out. There was a lot of water in the bilge which I drained. I think the bilge pump isn't working, another problem.

After draining the water, I briefly started each engine. This time the port engine started right up, but the starboard was balky. Finally it started.

After getting home I hooked up a hose and started them again. Each engine started quickly (port faster than starboard) and seemed to run well out of the water. Of course, it never runs more than 3500rpm when no load. Could it be ok now?

I once remember something similar happening before my father stopped using the boat. It was repaired and the shop said there was water in the carburetors.

Is that it? How do you prevent it from happening if so? I read some postings say the carbs need to be cleaned or rebuilt after similar symptoms were experienced.

There's a lot of discussion about the crappy gasohol we're forced to buy due to our corrupt congress and corn processors...ok not the place for that rant. Most say get some Sta-Bil or similar. Might that do the trick? Or do I need to pull carbs?

 

[Bills86e]

It never hurts to look inside of a set of carbs every few years, especially if you have any poor idling, surging, accelleration, or flooding issues. In fact, even without those issues, it is good to stop them before they start.

 

[mlebauer]

It never hurts to look inside of a set of carbs every few years, especially if you have any poor idling, surging, accelleration, or flooding issues. In fact, even without those issues, it is good to stop them before they start.

True, but when it was cleaned out after sitting for years, they removed and soaked the carbs. Don't know if that included a rebuild, I think it was just a cleaning. So the question is, does it need to be re-done given the problems I had recently?

 

[Dr Honda]

True, but when it was cleaned out after sitting for years, they removed and soaked the carbs. Don't know if that included a rebuild, I think it was just a cleaning. So the question is, does it need to be re-done given the problems I had recently?

I would. I would also check the water traps, and make sure they are clear.

If you think you have water in the fuel... then pour in Stay-Bil marine formula. It helps pass the water, and treats the current automotive fuels with alcohol in it.

problems with 2-stroke fuel supply should be taken very serious. If fuel isn't being transported correctly threw the engine... either is the oil.

 

[Dr Honda]

Last thing... you can't tell anything on the hose. A crap engine will run just fine without a load on it.

 

[Bills86e]

Are you checkong the fuel bowl cup (water filter/separator) every time before launch? you should be, and if a sign of water or contaminates continue, is time to re-clean. 720's need clean fuel to feed the thirsty carbs! Gas can go bad in 3-4 weeks and ethanol seems more prevelent in fuel these days, so we advise useing Marine Sta-bil in every fill-up. Your area migh be prone to selling water in the gas, so Always pre-check. A couple Oz of denatured alcohol can be used to help disipate water. A droplet in a carb can shut off fuel flow. Advise you do a quick-clean of your carbs internal filters as well. Read up on reading your spark plugs. Post the condition.

Do a compression test now to check each engines internal health, post results.

 

[mlebauer]

Are you checkong the fuel bowl cup (water filter/separator) every time before launch? you should be, and if a sign of water or contaminates continue, is time to re-clean. 720's need clean fuel to feed the thirsty carbs! Gas can go bad in 3-4 weeks and ethanol seems more prevelent in fuel these days, so we advise useing Marine Sta-bil in every fill-up. Your area migh be prone to selling water in the gas, so Always pre-check. A couple Oz of denatured alcohol can be used to help disipate water. A droplet in a carb can shut off fuel flow. Advise you do a quick-clean of your carbs internal filters as well. Read up on reading your spark plugs. Post the condition.

Do a compression test now to check each engines internal health, post results.

Thanks, all for the advice. I'm obviously a Noob to this but want to learn how to maintain the boat myself. And sorry for the delay, I was traveling for work this past week.

So far, after buying the supplies, I've added marine Sta-Bil, changed spark plugs, greased electrical connectors, greased the shafts, and checked fuses. Bilge pump fuse is shot, which would explain why it wouldn't work, duh. Old plugs were heavily carbonized and covered with oil gunk. They also were not gapped to 0.5-0.6. Sprayed the outside with WD-40 to clean up corrosion, sprayed some down the hole, gapped the new plugs, smeared spark plug grease on the threads to prevent lock-up, boot grease on the boots, and torqued it to 2/3 turn installing the new plugs. Engines both started right up afterwards, but I just ran them for 15sec or so since I didn't connect the hose. Also removed the fuel filters, they looked clean.

Sorry about the noob question, but where is the fuel bowl cup (fuel / water separator)? All I can find on the fuel system are the 2 screw on fuel filters. Is that it? There's a hose running from the fuel tank, separate from the fuel lines, toward the cockpit area. What is that for?

I may take it to the water to test. Since the carbs were cleaned last summer they may not need it, even though the symptoms seemed to say fuel problems. If it has fuel starvation problems I'll get to work pulling the carbs, but all the hoses involved make me nervous.

Another noob goof I now know I did was to put API-TC3 oil in last summer. Read someone who recommends draining the whole oil injection system. Looking where all those hoses run, that really makes me nervous. Would it hurt just to run the current supply (less than 1/3 left) dry then immediately fill with API-TC?

I don't have the tools for a compression test but will look into that and perform when I can.

 

[Bills86e]

Open front, remove basket, its by the steering, bowl unscrews. Check before each outing. More water means drain & clean tank time.

 

[mlebauer]

Open front, remove basket, its by the steering, bowl unscrews. Check before each outing. More water means drain & clean tank time.

Are you talking about a jet ski? This is a boat, 2001 Challenger with twin 717 Rotax.

I opened the cockpit instrument panel and removed the basket. Only steering controls, wiring harnesses, and the weed gate control are there.

Today I have it down to the left carburetor, will remove that soon to take a look. Someone who worked on it in the past was a bit sloppy, one of the 6 bolts holding the air cleaner is sheered off and there's a 4" strip of metal with 2 threaded screw holes just lying in the air clearner. Not sure what it's for. I'll take pics to see if someone knows.

 

[Bills86e]

Yes........anyway......cups is #30:

http://partsfinder.onlinemicrofiche.com/seadooforums/Seadoo_oem/Seadoo_JB.asp?Type=13&A=52&B=8