Replaced Air Filter, Fuel Filter, Oil and Spark Plug. Started for a few seconds, then died and hasn't started since. Probably the carb, don't know if I should try carb cleaner or go for a carb rebuild kit. Don't know what kit to buy either.
Start off with the full B & S engine number, Model - Code - Trim.
That way those in the trade with B &S on line can tell you the correct parts to buy.
As for you current problems, can be a few things, assuming the motor was working fine before you did the service.
Start by pulling the plug, look at it and smell it.
If it is wet or smells like fuel , it could be bad new spark plugs can go bad right out of the box, particularly when starting using old stale fuel. Pull the plug, give it a good spray with carb cleaner, starter fluid , contact cleaner, brake cleaner but not WD 40 or any similar product.
Before you try & restart, drop the float bowl, or undo the float drain plug, catch the contents in a container and look at it checking for liquid bubbles sitting on the bottom.
These are water and if seen, remove the fuel line to the carb and crank the engine, check for more water.
If all is OK, try starting again.
If the same thing happens again, try short burst of carb cleaner , starter fluid etc down the carb throat.
If you can keep the engine running then the carb is blocked and needs cleaning.