OutdoorKing Repair Forum Forums Repairs and Maintenance Questions on Chainsaws and Concrete Cutters Petrol Chainsaws and Concrete Cutters STIHL 038 Super Flooding

My Stihl 038 super won't start. It is getting too much gas on the spark plug when I try to crank it. Just replaced the carb hoping it was that but still it won't start. The saw was working fine a few weeks ago and then it just started doing this. I feel like it has fairly good compression. Any ideas?

The obvious cause of wet spark plug is no spark. I suggest you test the spark, by clamping the body of your spark plug to the cylinder head fins, connecting the HT lead to it, setting the controls in the start position, and pulling the starter. See if there is a steady stream of blue sparks across the plug's spark gap. If not, repeat the process with a new spark plug.

If it has spark, the next thing to check for is flooding - believe it or not, even a 2 stroke won't start if there is liquid fuel sloshing around in the cylinder head. To check for flooding, open the choke, remove the spark plug, set the throttle in the start position, and pull it over a few times with the starter. See if a spray comes out of the spark plug hole.

Often the kind of problem you are having comes from a weak spark plug causing a delayed start, and during that delay, the choke or other owner interventions cause a lot of fuel to accumulate in the crankcase. At that point you are in a tailspin: it won't start without getting rid of the surplus fuel, and it may not start anyway because the spark plug is weak.

Ive also seen spark plugs that will make a spark when tested outside the motor. But when you put it in the cylinder and ask it to spark a 7 or 8 to one atmospheres it wont do the trick.


Get an old plug that works and open up the gap and see what sort of spark it will throw. Depending on what Stihl and what ignition it should throw a fair gap.

I found the original plug and picked up a new one, set it to the specified gap. It fires when I have it out of the engine but still no luck when I try to crank it. All I can think of now is maybe its not firing hot enough?

mwb15,

Check your cylinder through the exhaust port to make sure that it is clean an no scoring on the cylinder/Piston. Also try to start with the muffler off but make sure you have ear muffs on.

If you are in the country area check for a wasp nest in the muffler as this will cause the same symptons that you have.