Small Engines (Lawn Mowers, etc.): Troybilt wont fire up, squirt bottle, initial repair

Question
QUESTION: Ok, When I first got this lawnmowere several years ago.  It won't fire and I took it in for a repair.  I can't remember what they fixed, but if was a little pricey like $350.oo.  They did put a cut off on the gas line and told me to manually turn that off every time when I finished using it.  I assume the carb was being flooded out.  Now, It has been running fine.  I go to crank it one day and it won't fire up.  I changed the plugs and now notice that it is leaking gas from the lines like crazy.  (I will probably replace the lines and filter), but this doesn't explain why it won't fire.  its sounds like it is flooded a little.  It is a 18 hp 42" with a Kohler engine I believe.  I have a friend who has the same lawnmower and he had to have the same initial repair and he can't remember what all it involved, but he also had to have a manual cut off installed on the line.  I want to repair it myself and not spend the big bucks.  Do you have any idea what this might be????
Thanks in Advance for any help.
Dale

ANSWER: First place to start is with the igntion system.  Do you have spark?

This video will help:

http://www.youtube.com/watch?v=drSep-Bp7wE&feature=related

The same technique can be used on your engine.  Remove plugs from engine, re-connect to spark plug wire, ground tip of spark plug and crank engine.  

Let me know if you have spark.

Eric

---------- FOLLOW-UP ----------

QUESTION: Yes, I do have a spark and a shock.  But still it won't crank.  What is next?

Answer
When you say crank, does the engine spin when you turn the key?  If so, and you have spark, will the engine try to start if you prime with fuel?  I use a small squirt bottle with fuel to squirt fuel directly into the carburetor to see if the engine tries to start.

Let me know it the engine tries to start when primed.
Eric