My Mcculloch chain saw has fire at spark plug gap. The plug is wet after trying to start it. Gas lines are clear. I can feel compression with my finger over the plug hole while pulling the rope. It was running fine last time I used it, drained tank & ran it till it stopped running. It just does not even act like it will start, can it be the reed valve stuck? Ready to buy a new saw. Stan

The most common cause is a wood chip stuck in the inlet or exhaust valve.
Check the compression.

Hi Mike firstly check the air filter is clear and if so try putting some fresh gas where the spark plug goes into the block. If it fires its the gaskets on the carb. If it doesn't it's the gaskets on the block and it wont fire due to the compression being at fault.

Yes. I recommend contacting your local authorized service center for assistance.

You may contact the manufacturer, download manuals, check fuel/oil ratios, order parts, find your local service center, and view other resources using these links:

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What is the correct fuel mixture for McCulloch products Chainsaw Trimmer...
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I trust this information has proven beneficial.

Often the cause is a failed fuel pump diaphram. Rebuild the carb... kits about $20. The diaphram works from engine vacuum pulses. Also the little flap type check valves go bad... the ethanol in gas doesn't help this problem...

If there is fuel to the plug, and a good spark it should fire, all i can think of is the ignition timing is out due to a sheared flywheel key.

No reset button. Remove the spark plug and test for spark--it should be blue and snappy with a fresh plug gapped at 0.020". If nothing, the entire engine case must be removed to troubleshoot an ignition problem. If the spark plug sparks, but it looks wet, try pulling the throttle wide open (with the spark plug out), no choke, and pull the engine through smartly several times to expel the excess fuel. Check the air cleaner to make sure it is not plugged. Hope some of this helps!

When I have a problem starting a saw this is what I do.

• Remove the spark plug and pour 5 ml (one teaspoonful) of fuel into the opening
  
• Dip the end of the sparkplug in fuel so the spark gap is wet
• Replace the sparkplug and try to start the saw

The fuel that you poured in should ignite and may be enough to cause the saw to start. You may need to repeat the operation 2 or 3 times. Do not be tempted to put in too much feul as it will only flood the saw.

If the saw was left away with fuel in the carburettor for a few months the fuel may have formed a gel in the jets of the carburettor. If the above method doesn't solve the problem you'll need to have a mechanic strip down the carburettor and clean the jets.

Engines require 3 things. Spark, compression and fuel. And chainsaw need 2-cycle oil mixed with the gas.

Assuming you have the right oil-gas mixture and a fresh batch of gas, and you didn't leave old gas in the saw all summer long since last November.

-Take off the dirty air filter and see if saw starts without filter. Do not run without putting in new filter.
-Check exhaust port for mud dobber home or screen clogged with carbon and dirt
-See if saw fires up after squirting WD-40 directly into carburetor
-Check gas line >>> pull gas line loose and see if gas flows out of tank to carburetor
-Take out spark plug > put finger over spark hole and pull cord >> do you feel suction that says you got compression?
-Put spark wire back on spark plug >>> hold spark plug so threads touch bare metal part of spark plug hole >>> pull starter cord and see if spark shows between plug and saw >>> suggest you not hold metal part of spark plug while pulling cord [you'll understand why]
-If spark plug shows spark, then your saw has spark ... so put in new plug and start fresh.

If your saw has compression, spark, and fuel it should start unless carburetor is gummed up because gas was left in tank.
Here is the final trick. Start the saw while spraying WD-40 directly into carburetor and see if you can keep it going with the WD-40. This might take a helper. If this does not work, then carburetor is bad or gas line is clogged at carburetor. Time to take it to the shop.

Storing a chain saw for longer than 30 days requires storage maintenance. Unless the storage instructions are followed, fuel remaining in the carburetor will evaporate, leaving gum-like deposits. This could lead to difficult starting and result in costly repairs. Never store a chain saw for longer than 30 days without performing the following procedures:
Remove the fuel tank cap slowly to release any pressure in tank. Carefullydrain the fuel tank.Start the engine and let it run until the unit stops to remove fuel from carburetor. Allow the engine to cool (approximately 5 minutes).
Using a spark plug wrench, remove the spark plug.
Pour 1 teaspoon of clean 2-cycle oil into the combustion chamber. Pull starter rope slowly several times to coat internal components. Replace spark plug.
Store the unit in a dry place and away from possible sources of ignition such as a furnace, gas hot water heater, gas dryer,etc. When removing the unit from storage, be sure to perform the following procedures:Remove spark plug. Pull starter rope briskly to clear excess oil from combustion chamber.Clean and gap spark plug or install a new spark plug with proper gap.Prepare unit for operation.Fill fuel tank with proper fuel/oil mixture.

This will help. Thanks, please keep updated. please do rate the solution positively .thank you for using fixya

The end of the plug where you are looking for the spark needs to be touching the head while you pull the chord. It must be grounded...