I have a Craftsman z6000 with a Briggs & Stratton engine. I have been having issues with low power and it eventually shutting off. You can especially tell when you engage the blades. It seems to be fuel related. There doesn't seem to be much fuel flow. At least it doesn't look like it from the fuel filter. If I disconnect the fuel line at the filter and let fuel come out, then reconnect it, it almost always works great after that. It's like it prime initially.
I had another strange thing happen the other day. I filled the gas tank while it was running. I don't typically do this, but I did this time. Once I got it all the way full it suddenly seemed to run much better. Then after a few seconds the fuel level would go down a little and it would run a little worse. Every time I topped it off it would speed up and run smoother until the fuel dropped a little. I'm not sure if this is related to air flow in the tank or pressure or something else. Is there anything related to the tank to check?
I had it gone over last year and they cleaned the carb etc. It seemed to be better for a bit after that and then reverted back this year. I guess it's possible the carb got dirty again with winter storage etc, although I did add fuel stabilizer. Any other ideas would be appreciated.
What briggs engine is this with model number so we can see what you are working on. Also post the model number information from under the seat so we can see how the system is configured. Does the engine have a fuel pump, and what fuel filter are you using.
The new fuels eat up the old fuel lines from the inside. Fuel hose can look "normal" on the outside and be clogged on the inside. Especially at pre-formed bends, elbows, and S-shapes.
These tiny bits of rubber then clog the fuel filter.
Highly suggest you replace ALL the fuel hose with automotive fuel hose, which MUST have the SAE J30 rating for ethanol fuel. Also a new fuel filter. Also use compressed air to blow out the fuel tank breather.... which is usually inside the fuel cap.
When the tank is full, fuel should shoot out of the fuel hose with a full diameter gush. IOW if you have 1/4" ID fuel hose, then a full 1/4" stream is what you should have going into the carb.
NEVER EVER leave fuel in the mower during winter storage.
#4
Hammermechanicman
Is it a gravity fuel system? Is the fuel filter a paper element type filter? If the answer to both is yes you need to change the filter to a screen tyoe filter.
