Small Engines (Lawn Mowers, etc.): Chainsaw Not Running, ketchup bottles, weekend mechanic

Question
I have a McCulloch chainsaw that is about 5 years old. It worked well for 3 years, faithfully starting up after each winter. I of course drain the fuel completely out and run the gas out before storing. Last spring after mixing fresh gas/oil, it did not start. Not even a sputter. Since I'm a "weekend mechanic", I don't have a lot of time to spend trying to fix it. I bought a Poulan 42cc chainsaw until I have time to spend on the McCulloch. Before I tear the McCulloch all the way down, what procedures do you suggest to diagnose and get my old chainsaw running?

Thanks for your help!

-Greg

Answer
Are you familar with priming engines?  I'd start by finding a small bottle with a tapered tip, kind of like those old diner style ketchup bottles.  Fill it with a little fuel/oil mix.  Remove the air filter to access the carb.  Squirt a little mix in the carb and see if it will try to start.  If it tries to start then the problem is most likely old, brittle carb diaphrams.

You can Google Walbro, Zama, or Tileston and find detailed repair manuals on their websites as well as the carb kit part number for your carb.

If it does not try to start after priming, check for spark.  If spark is good, replace spark plug and try to start again.  If it still does not try to start check the engine compression.

Eric