2002 GTI - runs fine for 10 mins then sputters / surges but wont go high rmp

[rmwilson]

My neighbor knows I am super handy with 2 strokes - and asked me to look at his 2002/2004 gtI seaDoos, The symptoms he said was runs fine for 10-15 mins then surges or does not rev out - he of course is not technical at all I tried to ascertain if it was fuel surging or like overheating and hitting safe mode or rev limiter i.e maybe over heating.

Going down the over heating path - I started to look at all cooling lines as to me sounded like it might be overheating then going into a safe mode (I am not sure if they can go into an over heat mode can they? (I know my 1990 yamaha waverunner could go into a over heat mode and limit rpms) - disconnected them ALL (exhaust, head, pump intake, exit etc) and blew air through them freely, pulled head off and really nice and clean I was hoping or expecting to see weeds or sand in there no such luck. Can the venturi bilge pumps get clogged up or cause any problems in cooling system lines? (Vacuum or blockage????)

I checked temp sensor - it has continuity but an open no resistance reading when at ambient temperature - I did try to warm sensor with a heat gun I heard it click.

I have scoured the internet found one guy saying rubber grommets (top hat shaped seals/ rubber bushings) (at the back of the machine where the pump connect to the haul) in the pump housing can collapse when warm restricting water flow - any way to test or verify this? (other than pulling out pump/jet and seeing how soft they maybe?)

can a fuel line start to collapse after they warm up? Or

What would electrical symptoms be on these machine - bad cdi bad rectifier,

Can any one give me any ideas and what to look for on how to trouble shoot these machines ( neighbor claims carbs were rebuilt by a shop and that did not fix the problem)

 

[mikidymac]

There’s no overheat mode it’s just an idiot light, nothing more.

Try opening the gas cap and see if that fixes it. When the check valve goes bad they create a vacuum after a few minutes and can starve fuel.

 

[rmwilson]

There’s no overheat mode it’s just an idiot light, nothing more.

Try opening the gas cap and see if that fixes it. When the check valve goes bad they create a vacuum after a few minutes and can starve fuel.

Interesting ... thanks for that. I will look into it certainly a valid idea and helpful response -

 

[burtshaver2021]

Check the gap between wear ring and impeller, to large of a gap can cause over heating issues, although the performance would be noticeably poor. Also, the shop the rebuilt the carb, was it a shop know to work on 2 stroke seadoo’s? I find a lot of marine mechanics and auto mechanics that are not familiar with them will put the cheapest rebuild kit in the carbs they can find, and that can cause issues.

 

[rmwilson]

Check the gap between wear ring and impeller, to large of a gap can cause over heating issues, although the performance would be noticeably poor. Also, the shop the rebuilt the carb, was it a shop know to work on 2 stroke seadoo’s? I find a lot of marine mechanics and auto mechanics that are not familiar with them will put the cheapest rebuild kit in the carbs they can find, and that can cause issues.

Something I'll certainly check ... 9 I was going to check carb pop off pressure ... at this stage not having ridden them I am guessing and and assuming it over heatimg ... ( there are two I started work on pne I may just take the other one out and get an actual feel what's happening) - thanks Burtshaver2021

 

[rmwilson]

Update to this thread ( a while in the making sorry folks) - FINALLy got the one machine into the water to test it for myself ... ( They are not my machines so have to work with owners schedule- It had a brand new battery, I had replaced the temp sensor, and had blown out all the coolant lines with compressed air. It started RIGHt up instantly, idle well as expected and after warm up it was responsive and running great .... It runs to me what seems very very smooth for 10 mins... and then at the 10 min mark something happens ( so its related to get itting hot) its very hard to explain but its almost like it goes into a limp mode or over heat mode but only sort of - the throttle is less responsive you can pull to the bar and then slowly picks up a bit of speed not a lot (10-15kms ish if i had to guess) - it does not feel like it sputtering or choking or bogging rather just down on power - significantly ... You have to sort of feather the throttle to keep it going ... it wont stall it jut wont respond...

so it only happens after it gets warm ...

I did try and do a compression test on it just cranking it over I think I got 110 psi based on my gauge which is low ... but the second machine has 140 psi and (and eledeglity has the same problem, I have not ridden that one...

 

[mikidymac]

If the compression really is 110psi that engine is done. Will the engine starting to seize and scuffing piston skirts it could act like you are experiencing when hot.

 

[rmwilson]

There’s no overheat mode it’s just an idiot light, nothing more.

Try opening the gas cap and see if that fixes it. When the check valve goes bad they create a vacuum after a few minutes and can starve fuel.

Any idea where this check valve is located and what it looks like? Can you find it on these fiche? https://www.seadoopartshouse.com/oemparts/l/sea/500d72e1f870020908257ea6/2004-gti-parts

or in the shop manual ( tried searching for it and could not locate it?) https://seadoomanuals.net/download/pdf/service/manuals/2004/2004-seadoo-shop-manual.pdf

is it 18 or 37 in this fiche? https://www.seadoopartshouse.com/oemparts/a/sea/601b0d6d87a8660914dd93ce/fuel-system

 

[burtshaver2021]

Any idea where this check valve is located and what it looks like? Can you find it on these fiche? https://www.seadoopartshouse.com/oemparts/l/sea/500d72e1f870020908257ea6/2004-gti-parts

or in the shop manual ( tried searching for it and could not locate it?) https://seadoomanuals.net/download/pdf/service/manuals/2004/2004-seadoo-shop-manual.pdf

is it 18 or 37 in this fiche? https://www.seadoopartshouse.com/oemparts/a/sea/601b0d6d87a8660914dd93ce/fuel-system

The check valve should be located up under the front of seat somewhere. It pushes into a grommet that goes through the hull. Look around in the hull, coming off the fuel tank will be a 1/4” fuel line that goes to a T fitting, with one hose going out under the rub rail as a pressure relief for the fuel tank and from the T in the other direction up under the seat.

 

[burtshaver2021]

It’s 37 that allows air in to the tank to avoid a vacuum