Small Engines (Lawn Mowers, etc.): Lawn Mower, briggs and stratton, rubber gasket

Question
QUESTION: I cannot crank my push lawn mower that is about 10 years old.  It has not been used much as I mostly use a riding lawn mower.
It is a Briggs and Stratton engine.  The numbers are hard to read but I think the Model is 90902, Type is 200582 or 2005B2, and Code is 020730501.  I have cleaned the carburetor and replaced the primer, diaphram, gasket and the keyway on the fly wheel. I removed the rubber gasket, ball and spring behind the primer and blowed air through it.  I have gas in it and get a spark when I try to crank it.  I cannot tell if the gas is getting into the cylinder.  Can you please suggest what else I might try.  Thank you.  Joe Hamilton

ANSWER: Remove the air filter and spray some WD-40 or use a primer bottle to squirt a little fuel directly into the carburetor throat.

If it starts then you know you have a fuel problem.

Eric

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

QUESTION: Had already tried that with starter fluid and it didn't crank.  Since that indicates not a fuel problem what else might it be?  Thanks.

ANSWER: Are you sure you have spark?  Are you sure the flywheel is not sheared?

Does the engine have compression?  

If you have fuel, spark, correct timing and compression is sure run.

Did you install a new spark plug?  I have had new spark plugs, right out of the box, not work.

Let me know.
Eric

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

QUESTION: My wife saw for the spark while I pulled.  Today just to make sure I tested the spark plug.  I took the spark plug out and put in a compression guage.  I then pulled on the lawn mower 4 times and got 60 pounds compression.

Your responses have been very prompt and I appreciate it.

Thanks again.

Joe

Answer
60 pounds should run.  Can you get a new plug and see if it will try to start with a new plug while priming the carb?

It has to run while priming if it has spark, compression, and the flywheel key is good...it has to or there is a problem with one of the three or more.

You should be able to start the engine by priming even with the carb removed.  Ever see those really old carbs that just dropped fuel into the intake valve?  Priming is the same thing.

Is the fuel good?  I have had some fuel that didn't look or smell bad but you could dip a screwdriver or similar tool in the fuel, try to light it with a lighter but the fuel on the tool wouldn't ever catch fire.

Let me know the results of the new plug and priming.

Eric