Briggs and Stratton 16 HP riding lawnmower was working just fine yesterday. Parked it overnight - returned in the morning engine would not crank, noticed gas leaking out of muffler when choke open. Took off air filter - it was full of gas, took off engine cover gas gushed up out of oil fill tube, more gas poured out of muffler ... something is wrong ... we don't know what ... suggestions?

I would say that your float stuck on your carburetor and allowed fuel to continue to flow and fill the cylinder and crankcase.

Yup, sounds like the float is stuck, this will not allow the needle to properly seat shutting off the fuel flow as necessary. Did it run out of gas? This may cause the float to stick as the lack of fuel in the float bowl allows the float to drop to low. You may also have a pinhole in the float.
Dean

Its probably time for a carburetor rebuild as well as an oil change. The ethanol in the gas today is just destroying the nylon seals used for the float valve located in the carburator. Give us your engine model and type so we can assist you further if needed.

Rarely is the float ever stuck, it's usually a bad float needle or seat that will not seal, but the result is the same.

Thanks for the advice - carburetor has been removed, cleaned, reassembled, and my husband is out merrily mowing! There was a great deal of smoke when the mower fired up - we decided that was from all the gas that was everywhere - not smoking now! Thanks again!

Hopefully you check back now that your mower is running........................................... ...CHECK THE OIL!!!! Is it thinned out with gas?? Drain it and replace it!!!! BEFORE IT'S TOO LATE!!

(right guys? good advise?):eek:

Hopefully you check back now that your mower is running........................................... ...CHECK THE OIL!!!! Is it thinned out with gas?? Drain it and replace it!!!! BEFORE IT'S TOO LATE!!

(right guys? good advise?):eek:

10-4.
Dean