Re: 250 HPDI problem!!!!
Hi Confused. You have a very common problem. When it first happened to me, my mechanic told me, "That is a very expensive problem. I need to take half the motor apart to change the VST filter." After doing some research online, I found very good directions, with pictures, and did the job myself. Search for "VST" "filter" "HPDI".
Gas flows into the motor and hits the clear fuel filter. Your problem is not here. The fuel then goes to the Vapor Separator Tank. This tank fills with fuel. As the name implies, vapor is separated here. There is a medium fuel pump located in a vertical position on the forward part of the VST tank. On the bottom of the fuel pump is the VST filter. It is located directly above the brass drain screw for the VST tank. If you service the VST filter yourself, DON?T remove the fuel pump from the top of the VST tank. It is a ***** to get back in correctly. It is possible to remove the bottom of the VST tank without disconnecting all of the hoses on top of the VST tank, or removing the VST pump. The trick is to remove the bracket on the bottom of the VST tank. This will allow the VST tank to slide down far enough to service the VST filter.
The medium fuel pump in the VST pressurizes the fuel to 40 psi. The fuel leaves the VST tank and hits the canister filter located above the VST. It is not hard to change, but be sure to read about it online before you try it. Also, there are Yamaha specific hose clamps that should be used on the fuel hose. I have seen people use hose clamps, but Yamaha techs will tell you that hose clamps will eventually fail. Having fuel sprayed at 40 psi on a hot engine is kinda scary.
For a dealer to replace both the VST filter and the canister filter, I bet an honest tech would charge no more than two hours of work. Add $40 for the VST filter, $40 for the VST gasket, $100 for the canister filter, and $20 for the two clamps. You should be out the door for under $500.
One last thought. Sodium Sulfate is the white powder that is clogging your
VST. Many people believe sodium sulfate is released from heated fuel in the VST. Ethanol fuel soaked with water will exacerbate the problem. Adding StarTron or Stabil should help. If you have water in your fuel, and you are not using the additives I mentioned, then your VST will foul again in 5-15 hours of running. Good luck to you.
