float height
If the Mikuni carb is leaking gas out of the overflow despite the petcock being off, it usually indicates a stuck or damaged float needle valve. This valve controls the flow of fuel into the carburetor; if it doesn't seal properly, fuel can overflow. Additionally, debris in the fuel system or a malfunctioning float can also lead to improper fuel levels, causing leaks. It's essential to clean or replace the float needle and inspect the float for any issues.
It may be caused by a poor needle and seat. The needle or seat may be clogged with debri allowing fuel to continuously flow into the bowl and out the overflow tube. Check this theory by removing bowl, and reinstalling fuel line and carb to engine and allow fuel to flow. Once flow has begun gently push float into the most highest point. Fuel should shut off. If it does not, then you need a new needle and or seat.
Your floats might be stuck.
yes, i have done it use the flange from a skidoo and drill the bolt holes out you will need a new throtle cable to match the carb and then just play with the jetting to get it to run right you might need a fuel pump as well the stock carb had a integrated pump that was junk
if your engine has a carb and is not fuel injected the fuel pump may be putting out more pressure and volume than the carb can handle. The rush of fuel may push the float down and hold it causing the carb to overflow. This would be a dangerous condition.
I had the same problem. I took the carb. apart, cleaned it and rebuilt it, and that seemed to fix the problem. I suspect some thing had got into the carb and was preventing the fuel intake cut out from closing properly.
could be a stuck butterfly on either the carb or throttle body depending on if your fuel injected or not. if not that, probably something very serious.
The Higher the Jet Number the Bigger the hole init so more fuel goes into engine to make it richer, the smaller = vice versa less fuel means lean running. some carbs a 120 means 1.20 mm diameter but on Mikuni it is lm flow (milliliter) flows. so depends on who makes carb.? but yah bigger is more fuel
float is stuck on bad if the bike has set up for a while clean carb on try some sea foam fuel treatment seems to work pretty good might check the fuel filter for trash rust dirt
Take the carb of and see if the carb floats could be filling with fuel and not shutting off the fuel intake to the bowl. Check the floats for liquid inside. If that's not it then check the floats for restricted movement. While your in there clean out the bowl and the float needle that is supposed to shut off the fuel flow to the bowl.
The 1992 Suzuki Quadrunner typically features a Mikuni carburetor, specifically the VM series. This carburetor is known for its simplicity and reliability in delivering fuel to the engine. It's a single carb setup, which helps in maintaining a balance between performance and ease of tuning. Regular maintenance and cleaning are essential for optimal performance.
Carb.? On the inlet fuel line to the carb.