Hi all - I have a 2001(?) quadRUNNER(not sport) 300 that is flooding the airbox with gas when it is running - it's also flooding the motor and killing it. It acts like a stuck float except the fuel flow is way more than I would think would come from a needle/seat.

So I notice a 'PRI' setting on the shutoff valve and chase the hose - this is obviously a primer because it dumps into the front of the carb. Are these known for failing and getting stuck in a Prime mode? Or should I be looking for a stuck float?

Thanks for any help - looks like a great site!
Scott

 

im pretty sure it should still run normally even on the prime setting. id check for a stuck float. the prime setting only bypasses the automatic vacuum fuel shutoff. the needle and seat should still stop the flow.

 

Something is WHACKED with this machine. I have both fuel lines off and it will run for 20 seconds at part throttle and then spew a couple of ounces of fuel out of the back of the carb and flood and die. I let it set for 10 minutes to dry out and it starts up and does the same thing again. I've done this 3 times now with the fuel lines completely disconnected. I don't have a clue where it's storing all this fuel since it has a tiny little bowl.

Is the diaphagm on top a pump? Is it storing fuel somehow? It looks like it just actuates the slide...

 

are you talking about a diaphragm on the fuel valve or a diaphragm on the carb itself?

 

The diaphragm on the top of the carb. I have the fuel valve completely removed from the system (I have removed both fuel lines from carb). As far as I know there is no way for additional fuel to get to the carb. I have run the machine again 3 times since my last post - all with no new fuel going into the carb and all with the same results.

 

Any other ideas anybody? I got 10oz of fuel to flow out of the back of the carb with the tank disconnected. There is no way the bowl was holding 10oz of fuel. I don't know OHV engines - I know car engines and 2-strokes...is there any way the owner flooded it badly and the fuel was sitting inside the motor and flowing the excess back thru when the engine ran?

Once I ran the thing dry and reconnected the tank everything seems to work fine. I just don't want the job to come back in a month with the same problem.

 

There would be no way for the fuel to stay in the engine it would run through the valves when they open.. i would say the floats are stuck high. i would try adjusting them down nd see what happens. you would be surprised at how much fuel is actually in a carb..