help 1998 seadoo gtx not running right

[spudato]

i have a 1998 gtx that i have had for a couple weeks now, it ran great up until yesterday. i am a newb to PWC's so i dont know that much about how many rpms are normal for WOT or top speed but i have a problem when i go to start it, wether the engine is warm or cold, i have to start it with the choke on for a second, weird thing is it runs fine after you start it using the choke for about five seconds, idels, dosent bog. it will run fine for 5 seconds, after 5 seconds if i havnt floored it and reached around 4000 rpms it will die,flat on its face. Say at 3000 rpms cruising, it will start to die and if you give it more gas it will just die. It wont restart unless you use the choke again, then it runs fine for 5 seconds. Like i said you have to floor it and get to around 4000rpms within 5 seconds or it will fall on its face. After 4000 RPMS it runs great very peppy no miss and it tops out around 6200 RPMS but it feals fine. it just wont run at all under 4000rpms. If i start it out of the water i can hold it at 3000 rpms but as soon as i hit the water it will die. I have a rebuilt engine, i have clipped the plug wires, new fuel filter up front, new spark plugs, and im running a 40:1 premix. I dont know if it might be a low speed adjuster, a bad fuel pump diaphragm, im pretty sure it's carb related but im open to any suggestions. Thanks, will

[John Kubiak]

Re: help 1998 seadoo gtx not running right

New spark plugs... Are they NGK BR8ES, gapped at 0.022" to 0.024"?

What else happened yesterday? Did you fill up with a lot of fuel? Did the problem occur right after the refuel?

It would be best to order 2 Super BN kits:
http://www.sbtontheweb.com/Merchant2...tegory_Code=35


And 2 carb base gaskets:
http://www.sbtontheweb.com/Merchant2...gory_Code=48-1

[spudato]

Re: help 1998 seadoo gtx not running right

New spark plugs... Are they NGK BR8ES, gapped at 0.022" to 0.024"?

What else happened yesterday? Did you fill up with a lot of fuel? Did the problem occur right after the refuel?

It would be best to order 2 Super BN kits:
http://www.sbtontheweb.com/Merchant2...tegory_Code=35


And 2 carb base gaskets:
http://www.sbtontheweb.com/Merchant2...gory_Code=48-1

I do have a pair of NGK BR8ES installed, when the problem occured i had 10 gallons of gas and oil in, witch it ran on the day before. It had been running great for about 15 minutes i was running around 3000rpms and it started bogggggging and hessitating bad so i gave it some more gas and it just boggged then died, it wouldnt restart so i took it home and cleaned the plugs they were soaked, it wouldnt restart until i pulled the choke then it started fine and ran great for seconds. I have already ordered an SBT base gasket for the carbs and will install those when they come in. thanks for the help,will

[djd94xp]

Re: help 1998 seadoo gtx not running right

did it happen all of a sudden or progressively got worse.

[spudato]

Re: help 1998 seadoo gtx not running right

did it happen all of a sudden or progressively got worse.

WELL at first it was just a hessitation then it would go, then it developed into a bogging down, acted like it had no power and it bogged down and quit. spark plugs were soaked, today i ran it all day, at high rpm's It ran great same problem at low rpm's, but i checked the plugs after i pulled it in and they looked great a nice brown tint not oily, not extremly dry. but when i check the plugs after trying to start it without the choke they are oily.

[tyreman05]

Re: help 1998 seadoo gtx not running right

you ar mixing fuel with oil in your tank, if you dont shake jetski for at least 30 seconds before starting it oil will stay at bottom of tank and engine will stop .

[spudato]

Re: help 1998 seadoo gtx not running right

you ar mixing fuel with oil in your tank, if you dont shake jetski for at least 30 seconds before starting it oil will stay at bottom of tank and engine will stop .

hmm, well i would think that my drive to the lake would shake it up enough, i trailer it to and from the lake, about a 10 minute drive. would that shake it up enough?

[parrothd]

Re: help 1998 seadoo gtx not running right

Yes, more than enough..Just adding the oil and launching the boat is enough to mix it completly, no need to shake it.. You're mixing 2 liquids designed to mix easily, not pancake batter... :) Have the carbs rebuilt, and check all the fuel lines/filters

[spudato]

Re: help 1998 seadoo gtx not running right

ok i went out on the lake today, and filled the boat up with 93 oct. and ran a litttle leaner mixture 45:1. the boat ran the same for the first 15 minutes than it started to run really good. no miss from idel to 6200. it just ran better the more i drove it. i ran it about two and a half hours. not sure why the 93 oct and the leaner mixture caused it to run better, only thing i can think of was that i might have got water in my fuel from old gas.

[seadoohx]

Re: help 1998 seadoo gtx not running right

check your fuel selector..
flat on face usually means lean fuel and this is a common culprit