yamaha stop running

[dnoonan923]

my cart ran great 3 weeks ago, then it stoped getting gas, so heres what i have done i have replaced the base seal, cleaned carb and adjusted the intake vAlve and exaust intake. i am still suspect of the piolet jet even though i have cleaned\blown it out 3 times. please any ideas?

[smallblock450sl]

Did you check the fuel pump? Take the line off at the carb and crank it over, it's not real high pressure, useually a pulsing steam. Had one today, the guy said he hasn't getting fuel, well the accelerator cable #1 (from pedal to govenor) was broken and hasn't opening the throttle shaft. Just some things to look at.

[dnoonan923]

the fuel pump is working and compresion is 163 and the cabels are all in good shape. here is the whole problem i am getting fuel to the carb but its just sitting in the bottom of the bowl, i have replaced the float and float neadel

[dnoonan923]

ok the fuel pump is working and compresion is 163 and all cabels are good. i am getting fuel to the carb but it just sits in the bowl the float and float needel are new which is why i think its the piolet jet

[smallblock450sl]

Originally Posted by dnoonan923

ok the fuel pump is working and compresion is 163 and all cabels are good. i am getting fuel to the carb but it just sits in the bowl the float and float needel are new which is why i think its the piolet jet

Sounds to me like the "main jet" is plugged (it's the one in the float bowel). A good carb cleaning is in order. There very simple to work on. Good luck

[sho305]

Most of these carbs if you want to verify its working, you can take a can of carb clean with the hose...do not spray yourself in the face and this is hard on the hands, but... Take the carb off and stick the tube up the main in the center of the bowl. Look in the carb venturi and you will see it squirt out the little brass tube at the bottom. That means the main is clear. Now look at the air intake of the carb, on the side or bottom is a couple air jets. One usually goes to the main and will blow out the main and the brass tube inside (emulsion tube, this tube may fall out with the main jet). The other is for the idle circuit. If you spray down that one you should see some tiny holes at the edge of the butterfly plate (when closed) at the engine end of the carb inside. If you have an idle mix screw it may be near or at those holes. If it sprays out those holes they are clear, usually some may come out the main or near it....because the air from these mixes with the fuel. If this is ok then look for an air leak in the intake, or check for air flow is the engine sucking in air? If you choke it and spin it over is the plug wet though it may take a little while. If you are sure its no gas then it should run on starting fluid.

[spriddle]

Have you replaced fuel lines lately? If so, make sure you went back with the correct size: 1/4 and 1/2 if I remember right. I'd have to check for sure. But Yamaha's are very picky about fuel line size.

Also check the little vacuum hose going toward the back of the engine. It helps pulse the fuel from the fuel pump to carb.