Stihl MS 250: Common Problems and Troubleshooting Tips
Hello everyone, today we’re going to discuss the common issues and solutions of the Stihl MS 250 chainsaw, which is quite popular among homeowners. While this saw is a great tool, it can encounter some problems from time to time. Here’s a guide on the most frequently encountered issues and how to overcome them.
Engine Running Lean and Bogging Down
If your Stihl MS 250 chainsaw runs weak, sputters, and struggles under load while cutting, there could be a few potential reasons.
Clogged Air Filter Over time, sawdust and debris can accumulate, restricting airflow to the carburetor and resulting in a weak fuel mixture. To solve this issue, remove and clean or replace the air filter.
Dirty Carburetor Similarly, resin, varnish, and dirt buildup in the carburetor can obstruct air intake. Cleaning the carburetor with carb cleaner and compressed air will restore proper airflow and fuel mixture.
Faulty Fuel Pump A malfunctioning fuel pump can also cause lean running by failing to deliver fuel from the tank to the carburetor. Test the pump and replace it if necessary.
Engine Won’t Start
If you’re pulling the starter cord but the chainsaw engine refuses to start, there are several components to check:
Ignition System Faulty ignition components like damaged wiring, a defective electronic ignition module, fouled spark plug, or a faulty ignition coil can prevent the engine from starting. Test and replace any faulty parts.
Clogged Air Filter As mentioned earlier, a dirty air filter is a common culprit for starting issues.
Dirty Carburetor Varnish buildup in the carburetor can block passages and restrict fuel flow, preventing starting. Thoroughly clean the carburetor.
Fuel Supply Ensure that fuel is reaching the carburetor. The fuel filter may be clogged, or the fuel lines may be cracked. Replace any defective parts.
Spark Problems
Without a good spark to ignite the fuel mixture in the cylinder, the engine won’t start. Spark issues in the MS 250 are usually electrical:
Spark Plug Inspect the spark plug. If it’s fouled or damaged, replace it. Ensure the gap is correctly set.
Ignition Coil The ignition coil converts low voltage from the magneto to high voltage for the spark plug. Test the coil and replace it if faulty.
Compression Problems
If pulling the chainsaw is difficult and it lacks power, it likely has low engine compression, usually caused by:
Damaged Piston A scored or stuck piston will reduce compression. The piston must be repaired or replaced.
Damaged Cylinder Similarly, a cylinder scored from lack of lubrication or with stuck rings will cause compression issues. This requires cylinder repair or replacement.
For significant engine issues like damaged pistons or cylinders, it’s best to take the saw to a professional repair shop.
Extra Tips from a Carpenter
As a carpenter, you can prevent many common problems with regular air filter changes and carburetor cleaning. Additionally, cleaning and lubricating your chainsaw after each use will prolong its life. After cutting, always sharpen the blades to ensure precise cuts. With these basic maintenance and repair steps, your trusty Stihl chainsaw will be back in action in no time.