Small Engines (Lawn Mowers, etc.): mac 3516 chain saw, starter fluid, exhaust port

Question
Recently replaced the oil pump mechanism, but now it won't start I replaced spark plug and made a fresh batch of fuel Mix. I checked and the spark plug is sparking looks a bit weak, but it does have a spark....but unit will not start. any suggestions

Answer
Hello Juan:

Did you Check the Exhaust Port and Muffler? If Either of these are Restricted with Carbon Deposits, then the Engine May Run at Idle but will Flood when you Try to Rev the Engine above Idle. The Following is a Basic Instruction File for Doing a Diagnostic on the Engine for this Problem. Any Input is Appreciated. **Remove the Muffler and Make Sure the Exhaust Port is Clear. If it is, then Try to Start the engine with the Muffler Off. If it Starts and Runs Properly, then Clean the Spark Arrestor Screen in the Muffler or Replace the Muffler if Required. Will the Unit Start if you Use Starter Fluid or Gas in the Carburetor Throat and Try to Start the Unit? Does it Start and Quit? Was the Unit Starting and Running Correctly before you Replaced the Oil Pump? Thanks.

Respectfully

John