150 HP Carbs Spewing Fuel
Engine is a 2004 Yamaha 150TXRC. Engine has 130 hours and has run great the past two seasons. Last week I decided to winterize (fog) the motor and store the boat until Spring. The engine hadnt been run for about a month. I removed the intake silencer and while pumping the bulb to start the engine, I noticed fuel spewing out of both throats of the middle carburetor and one throat of the lower carburetor. I pulled the center carb today and removed the float chamber. It was squeaky clean inside and both floats moved freely. I then removed the floats and inspected the needle valves using a 10X magnifying glass. The rubber tips show no wear or deformation and are pliable . They look new. The valve seats are not removable but they also look ok. I then reinstalled the needle valves and floats and checked the float heights according to the Yamaha Service Manual. The manual calls for the float height to be 16mm plus or minus 0.5mm with the gasket removed. One float measured 19.24mm and the other measured 19.56mm. Could this be the cause of the flooding ? What I cant figure out is how they could get so far out of spec. Could it be that they werent set up correctly at the factory? Should I replace the needle valves? As previously mentioned, the engine runs and idles fine. In fact, probably eighty percent of better of the engine run time has been at idle speed trolling.
One more question. The manual states under the heading DISASSEMBLING THE CARBURETOR
Before disassembling the carburetor, make sure to note the number of times the pilot screw is turned out from the seated position to its set position. The problem is the manual does not identify a pilot screw in the parts breakdown depiction. It shows a pilot jet and a pilot jet plug with the pilot jet plug having a torque setting of 2 Nm, 2.2ft lb. The manual goes on to state under ASSEMBLING THE CARBURETOR that Before assembling the carburetor, make sure to turn the pilot screw the same number of times, as noted before disassembly, from the seated position to the set position. Could this be referring to the pilot jet itself? I havent removed any of the jets.
Any help will be greatly appreciated.
Engine is a 2004 Yamaha 150TXRC. Engine has 130 hours and has run great the past two seasons. Last week I decided to winterize (fog) the motor and store the boat until Spring. The engine hadnt been run for about a month. I removed the intake silencer and while pumping the bulb to start the engine, I noticed fuel spewing out of both throats of the middle carburetor and one throat of the lower carburetor. I pulled the center carb today and removed the float chamber. It was squeaky clean inside and both floats moved freely. I then removed the floats and inspected the needle valves using a 10X magnifying glass. The rubber tips show no wear or deformation and are pliable . They look new. The valve seats are not removable but they also look ok. I then reinstalled the needle valves and floats and checked the float heights according to the Yamaha Service Manual. The manual calls for the float height to be 16mm plus or minus 0.5mm with the gasket removed. One float measured 19.24mm and the other measured 19.56mm. Could this be the cause of the flooding ? What I cant figure out is how they could get so far out of spec. Could it be that they werent set up correctly at the factory? Should I replace the needle valves? As previously mentioned, the engine runs and idles fine. In fact, probably eighty percent of better of the engine run time has been at idle speed trolling.
One more question. The manual states under the heading DISASSEMBLING THE CARBURETOR
Before disassembling the carburetor, make sure to note the number of times the pilot screw is turned out from the seated position to its set position. The problem is the manual does not identify a pilot screw in the parts breakdown depiction. It shows a pilot jet and a pilot jet plug with the pilot jet plug having a torque setting of 2 Nm, 2.2ft lb. The manual goes on to state under ASSEMBLING THE CARBURETOR that Before assembling the carburetor, make sure to turn the pilot screw the same number of times, as noted before disassembly, from the seated position to the set position. Could this be referring to the pilot jet itself? I havent removed any of the jets.
Any help will be greatly appreciated.
