Yamaha gp1200R Flooded with fuel??

[ktyamaha36]

What could possibly be the cause for the carbs to be leaking fuel into the engine while the ski is not running?? Over 2 days it flooded the whole engine compartment. Pulled the carbs, checked everything out. It all looks good. Anyone had this problom before??

[PWC-abuser]

Re: Yamaha gp1200R Flooded with fuel??

That sounds really strange. That would happen if you had excessive pressure in the tank, or else there was some sort of siphon action taking place.

Some siphoning might take place if the tank is full, and it has a break in the line somewhere that allows it to come out.

Do you see any leakage when the machine is running? You might not because the bilge pump would take excessive liquid out of the hull. Try to run it on a host for a while and see if there is any accumulation ...

[Madfish]

Re: Yamaha gp1200R Flooded with fuel??

I never had that problem before, but I would check the gas lines and make sure there are no cracks anywhere, the most likely location for a crack would be where there is a clamp or zip tie (always best to use zip ties). I would also make sure you have the factory yamaha fuel filter, mounted in it's proper location which is higher than the gas tank.

[dsolie]

Re: Yamaha gp1200R Flooded with fuel??

let me guess, nice hot sunny FL days, ski sits outside??

The gas inside the tank is being pressurized from the heat. This is normal, but you have check valves that allow the tank to expand as necessary, and allow air in and out.

Sounds like one of your check valves are stuck, and the pressure is forcing the fuel past the needle and seat assemblies in your carbs.

Another way to test to see if it's the check valves is to keep the gas cap off for a day. If it STILL fills up with fuel, then you have failing needle and seats...