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Troubleshooting and Maintenance Tips for Craftsman 25cc Weedwacker

Maintaining your lawn can be a simple, straightforward task when you have the right equipment that’s in good working form. If Craftsman is your brand of choice, then you probably already know that their 25cc Weedwacker is dream yard equipment.

It is lightweight, easy to start, powerful, and big enough to get the job done faster than most models out there. It boasts a multi-position adjustable handle that reduces vibration and operator fatigue. Plus, it’s not super loud and breezes through tough overgrowth with no problems.

Craftsman 25cc Weedwacker Problems

Craftsman 25cc Weedwacker

Unfortunately, even a string trimmer of a largely popular brand may sometimes malfunction and refuse to start. Instead of getting frustrated when this happens, check your weedwacker for several common problems that keep it from functioning as it should be.

Engine Problems

Most challenges with gasoline-powered weed wackers are fuel-related. It’s either the fuel is contaminated with water or it isn’t mixed with oil in the appropriate proportion. To resolve this issue, you usually have to disassemble and clean the carburetor.

In the event that the machine is hard to start, the problem is often due to a worn or improperly gapped spark plug. Note that electric weed wackers don’t often experience engine problems, but when they do, it’s usually caused by overworking the engine by cutting weeds that are too long or too thick.

However, most of the very small gas engine tools, like that of the Craftsman 25cc Weedwacker, use mixed fuel. Most of them have a filter in the fuel tank attached to the fuel line. People don’t always mix the gas and oil as they should to blend properly.

Pouring gas directly into the small engine fuel tank causes the filters (which are located in the lowest part of the fuel tank right where pure oil sinks) to become like tar over time. Old fuel lines are also a common problem with these engines as they crack or plug up-small diameters.

To fix, clean out the fuel tank, replace the fuel line and filter and then start to see if it works. If that doesn’t work, you probably have a bad hose or a bad hose connection that is sucking mostly air rather than delivering full fuel to the carburetor.

String Problems

If the string has a diameter that’s too large for the machine, it can overwork the engine and lead to engine failure. When you’re working with the proper-sized string, the most common problem is the string failure to advance automatically.

This is often caused by the accumulation of grass and debris around the head. On the off chance that the string doesn’t advance, the weedwacker won’t cut efficiently, and you might be forced to stop frequently and pull out the string manually until you have a chance to clean and lubricate the head.

Fuel Problems

Your Craftsman 25cc Weedwacker may fail to start due to fuel-related issues. First and foremost, check whether there’s enough fuel in the tank to power the trimmer. If the fuel level is low, the trimmer may fail to start. Simply fill the tank and try to start the trimmer.

However, if the fuel is leftover from last year, consider replacing it with fresh gasoline. Make sure that you have the proper fuel mix ratio of 50:1 for your weedwacker.

Spark Plug Problems

If your weedwacker refuses to respond in any way when you try to start it, then the problem may be due to a dirty, faulty spark plug. Cleaning the park with a wire brush to remove dirt or corrosion may allow a connection that restores the trimmer to working order.

If that doesn’t work, then simply pull off the spark plug cover and remove the old spark plug. Replace the spark plug as well as the spark plug cover. Then try starting the trimmer again.

Other Malfunctions

In some cases, too many attempts to start a trimmer can lead to a flooded engine. If that happens, position the weed wacker’s choke lever to “run” and pull the cord to remove excess fuel. You might have to repeat the procedure several times until the engine starts.

As mentioned before, a clogged air filter can cause your weedwacker to remain dormant. Inspect the air filter for dirt and debris. Clean and replace the air filter, if necessary before trying to start the machine again.

A clogged or dirty air filter may also keep fuel from reaching the carburetor. In that case, remove the faulty filter and replace it with a new one before attempting to start the trimmer again.

How Does the Craftsman 25cc Weedwacker Work?

Craftsman 25cc Weedwacker

The Craftsman 25cc Weedwacker is simply a lightweight string trimmer that works by using a rapidly spinning microfilament string that becomes stiff enough to cut grass and weeds.

Most models in this category feed a new string automatically as the old string wears out, dispensing with the need for heavy metal blades that require sharpening. Mechanically, the 25cc Weedwacker functions much like a handheld lawnmower.

Engine Operation

Similar to other powerful string trimmers, the Craftsman 25cc Weedwacker is equipped with a 2-cycle engine type that uses a mixture of gas and oil. When the operator pulls the cord to start the engine, the permanent magnets on the flywheel energize an ignition coil and send an electric current to the spark plug.

It starts firing with each revolution of the wheel, igniting fuel in the combustion chamber, and driving the crankshaft.

On the other hand, with an electric or battery-powered model, electric current rotates the flywheel and drives the crankshaft. These models start as soon as they have power. You’ll have to manually start gas-powered models by pulling a starter cord.