Thread: After Carb cleaning on 25 Hp Tahatsu

I just pulled the Cover on the motor ---- The Choke linkage had not been connected, So, when I had pulled the choke out, was not the reason it flooded... there are two adjustments, the Needle valve on the side and a screw that is to the Throttle Plate.. I hooked the choke back up

I am thinking maybe your float valves not shutting and pressure from the tank from the warm weather is forcing some gas in. I have never seen or had a two stroke motor that did not require at least a second or two of choke on a cold start even in summer. Now once they are warm in summer you can very easily flood one,especially if it has an electric prime. Can you pump your primer bulb up until it gets real hard and then will it stay that way for a while if you don't start the motor ? That's about the only thing makes any sense to me based on what your saying.

Those loose chokes can flap shut.....If they have the ball type linkage(like the M50D2) a couple of wire ties on both sides of the pivot will keep it together.

Could it be that since the linkage to the choke was disconnected that the motor needed the choke operation in order to start and was not flooded?

I had made Plywood doors to Cover the Fuel tank and Batteries to keep the sun from baking the plastic tank. With the vent in the tank open I dont think it had any pressure in the tank. The reason I believe it was flooded was how much smoke there was. One sure way to prevent this flooding is to disconnect the fuel line and empty the fuel pump and Carb... I was thinking that the needle valve might be open too much. The screw for adjusting the Throttle plate was not touched

If the needle valve is not closing off, steady pressure on the primer bulb will cause fuel to overflow the carb in a static test. Leaving the fuel line connected can cause a flooded "first start" condition. Especially in hot summer time conditions. The fuel in the line between the carb and primer bulb has only one direction to travel as it expands from heat. The needle can be forced open by the increased pressure. The primer bulb contains an anti flow back check valve that will prevent the fuel from returning to the tank. You may also be set a little rich on the idle mix screw if you aren't having to use the choke at the beginning of the day. From a lightly seated position, the adjustment screw should be about 1 1/2 turns out. The screw that adjust the throttle plate is the idle speed adjustment and should not have any bearing on your issue if the motor was running properly before.

Thanks again --- the choke has a return spring that will always have the plate open unless the choke is pulled out. The Needle is set at 2 turns open, that is what most Lawn mower engines are set. I will go out and hook up the water and set things correctly. The next trip to town I will get two new plugs. the ones in it have been in over a Decade.

Originally Posted by Fish on Line

Thanks again --- the ones in it have been in over a Decade.