Small Engines (Lawn Mowers, etc.): failure to start, exhaust ports, flood damage

Question
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Followup To Marc
         I have spark and fuel going to the engine..it turns over ok but will not run.I have sqirted fuel into the carburetor but does not make any difference,I have checked all switches and  all seem to be in good order.....but still no noise.  What have I missed here?  are there any further checks that I can do to track down the trouble
         L.Cole
Question -
Marc
   I have a Sears 10 hp rider mower that suffered flood damage...I have replaced the ignition switch,solinoid, and a new sears carburetor.plus de carbonising,
   I have spark and fuel flow the motor turns over ok...but will not fire
   Iam at a loss here....can you help?  It sure would be appreciated.
         Thanks     L.Cole
Answer -
First, check for spark.  Remove the spark plug and place it against ground and check for a spark while cranking over.  It's possible that one of the safety switches (neutral start, clutch, blade) could have been damaged by water or the ignition module could have.  If you have no spark, remove all of the shut off leads from the engine and check again.  If you now have spark, you will need to check, one by one, all of the safety switches to find the defective one.  If you still have no spark, the problem may also be the ignition module itself.   Hope this helps.

Answer
If you have spark and fuel, the only problem left is compression.  I can't think of how compression would be affected by flood unless the muffler has been filled up with enough debris to plug it.  You could try unbolting the muffler and attempt to start the engine.  If this is the problem, you will need to figure out a way to unplug the muffler or replace it.  If this doesn't help, you will need to dig deeper to look for plugged intake and/or exhaust ports, stuck valves (debris underneath them), etc.  Hope this helps.