NEED HELP BAD

[spongerssuck206]

01 GTX seadoo 720cc
Took my ski out for the second time ever today after picking it up from the shop. Spent 3 hours sitting in the ocean waiting for harbor patrol to come pick me up.

My ski would not start it turned over but would not start. It turned over until the battery finally died on me. It didn't even chug at all maybe 3-4 times it sounded like it wanted to start but didn't. The shop mechanic said he replaced the fuel pump, computer, cleaned the carb, jet pump, drive shaft, and fly wheel prior to this run today. But it still lags in power and doesn't have the throttle response that I have see from other skis. What could be the problem any help is much appreciated

UPDATE EVEN THO NO ONE RESPONDED.
It runs out of water with a garden hose sounds fine still doesn't seem to have the throttle response it should have. So it seems it runs out of water but not in water. IDEAS??

 

[mikidymac]

First there is no 2091 GTX 720.
What’s your compression?

 

[Digdog]

I would replace the reeds and check the RAVE valves, the back pressure while sitting in the water seems to be just enough to stop air/fuel flow through the engine

 

[spongerssuck206]

First there is no 2091 GTX 720.
What’s your compression?

it might be a GTS? then the stickers on it are gone so i could only go off what the mechanic i bought it from said

 

[spongerssuck206]

First there is no 2091 GTX 720.
What’s your compression?

the front cylinder was putting out 132psi and the rear was putting out 135

 

[mikidymac]

Compression is good and a 720 doesn’t have reeds or RAVE valves.

 

[mikidymac]

I always go fuel system first.

What does the “mechanic “ say about the poor running? Sounds like he replaced a lot of unnecessary parts.

 

[spongerssuck206]

yeah he said that it ran fin up in the lake he has near by. but his elevation 3200 to 4000ft. im at sea level so if the guy re jetted the carb for that elevation it would be flooding the engine right? i pulled the plugs they are black and oil on them so i think im going to get the carb rebuilt to stock and have it jetted for sea level. My friend says that the fuel pump could be the issue but it looks like there is a new fuel pump on the tank already

 

[WhiskeyD]

Download the service manual and it will help you a lot. There is no fuel pump on a 720. I'm guessing your carbs need to be gone through again.

 

[mikidymac]

They run rich at altitude so you lean them out because there is less oxygen.

If you bring it to sea level you would be lean. I suspect he didn't do something correct in the carb or used cheap parts.

BTW: Your ski does have a fuel pump but it is integrated into the carb itself. IF you have an external fuel pump added something is really wrong.

 

[spongerssuck206]

oh is that what those one way chambers are on one side of the carb. i took it off to look at the jets and clean it and its like no carb i have ever seen before lol

 

[etemplet]

You carb could be leaking air. I've come across a few that do that. Read Mikydymac's Carb thread, it will help you. Take your time and pay attention to the details.... those carbs are finicky by my standards. Keep them happy.

 

[Digdog]

Maybe look at this page and see if it helps, SEA DOO ENGINE FAULT FINDER SEADOO ENGINE FAULTS FUEL PROBLEMS FOR SALE SEADOO 230 KENT JETSKI BOMBARDIER BOATS PARTS SALES SEA-DOO SERVICE ACCESSORIES SUSSEX SURREY ESSEX LONDON WHITSTABLE HERNE BAY