[davnix]

I have a 15.5hp briggs & stratton mower which was running OK went to start it and it wouldn't turn over I checked the battery all OK then I noticed fuel running out exaust, oil seems to have fuel in it?? Can you help?

[Peter Wilson]

Sounds like your needle and seat is either blocked open with a bit of dirt in it, (the needle and seat is in the carby, when the float in the fuel bowl goes down, it opens the little hole that is blocked off by the needle and seat. The needle is usually a little brass pin with a rubber tip that fits into a seat when closed.)
This lets fuel run straight through the carby into the barrel.
You will have to puul the bowl off the carby, remove the pin holding the float, careful not to lose the needle in the grass! (put a sheet around you on the ground).
Blow through the fuel line to clear any blockage and re-assemble. It would be a good idea to empty your fuel tank and rinse it out with clean petrol.
Remove your spark plug and turn your motor upside down, if possible, and turn the motor over with the starter cord until no more petrol blows out of the plug hole.
Clean the plug carefully and make sure it is dry of any petrol. Replace it, fill it up with petrol and away you go!
It may be a little hard to start at first, as there will still be petrol residue in the barrel/piston area. You may have to dry the plug a few times. When it starts, let it run to clear out the barrel of all fuel.
You may also need a new needle and seat if it is worn and if that is the problem.
Cheers :)