Engine revs out of control please help

[Bill Grieve]

So I just rebuilt this 1994 seadoo GTX with the 650cc engine..It starts but goes to full throttle right away..I have the low speed jets turned in all the way and the throttle cable is lose ..It doesn't matter what the low speed jet is set at it does the same thing..I messed with the high speed jet and that doesn't do anything either..I was wondering what causes that ? Please help thanks

 

[Ankeneyou]

You have an air leak somewhere. It can be carbs, carb gasket, rotary valve to carb flange, fuel valve, fuel lines, crank seals, etc.

 

[pwgsx]

Air leak and set carbs to spec, dont keep adjusting them. That will not fix anything!!

 

[Bill Grieve]

Thanks guys I will have a look

 

[bell99man]

Spray some carb cleaner at the suspected areas. If it chokes it down a little, you're in the right spot. ONLY run that thing like that in very short intervals. The extra air will really shoot the piston temp through the roof.

 

[mikidymac]

Spray some carb cleaner at the suspected areas. If it chokes it down a little, you're in the right spot. ONLY run that thing like that in very short intervals. The extra air will really shoot the piston temp through the roof.

If it goes full throttle as soon as it starts I do not recommend starting it again and using carb cleaner. At a wide open runaway there is a good air leak. The safe way is to check for the obvious like a carb base gasket or do an actual leak down test.

If it does run away first pull the choke and flood it out. If that doesn't work hold the throttle wide open and hold the stop button or pull the lanyard. It should cool it enough to make it stop.

 

[Bill Grieve]

Thanks all it turns out there is a screw on the carbs that opens the throttle and that screw was holding it wide open once I fixed that it was fine for about 15 minutes of driving and the engine locked up I think it's a bad crank...It to sell for parts and buy something different thanks for all your help