Stihl String Trimmer Parts

Stihl String Trimmer Carburetors, Spark Plugs & Fuel System Parts

Stihl string trimmers are built to last, but hard starts and rough running usually point to one culprit: the carburetor. Ethanol in modern fuel gums up the float needle, jet, and internal passages — especially if your trimmer sat idle for weeks. A carburetor kit often brings it back to life without the full replacement cost. If the trimmer cranks but won't stay running, check the spark plug next; a fouled Champion RJ19LM is the second most common fix.

Beyond the engine, your Stihl FS series trimmer depends on a reliable fuel delivery system and a responsive trimmer head. Cracked fuel lines, stuck primer bulbs, and jammed spool heads are quick repairs that keep you cutting through the season. Use your Stihl model number (FS45, FS55, FS90, FS111, or FS131) to find OEM parts that fit exactly.

• Carburetor and rebuild kits: hard start, runs rich or lean, won't idle
• Spark plugs: fouled plug, weak spark, won't fire
• Fuel lines and primer bulbs: cracked lines, primer won't draw fuel
• Trimmer heads and spools: line won't feed, spool jammed, head cracked
• Recoil starters: pull cord stuck, won't recoil

Stihl String Trimmer Parts: Answers to Common Questions

Why won't my Stihl FS trimmer start after sitting all winter?

Ethanol fuel left in the carburetor gums up the jets and float needle over weeks of storage. Start with a carburetor rebuild kit — it includes new gaskets, seals, and a clean jet. If that doesn't work, a full carburetor replacement is the next step. Always drain the fuel tank and run the trimmer dry before long storage, and use fuel stabilizer in the off-season.

What's the difference between Stihl trimmer head sizes, and how do I load the right line?

Stihl FS series trimmers use different bump heads depending on the model — FS45 and FS55 use smaller heads than FS90 and FS131. Each head has a line diameter spec:.065" to.095" depending on the head type. Load the correct diameter to avoid jamming and poor feeding. OEM Stihl trimmer heads maintain the right spring tension and feed mechanism — aftermarket spools often cause line-feeding headaches.

My Stihl trimmer spark plug keeps fouling. Should I replace the plug or the carburetor?

A fouled spark plug (black, wet, or carbon-coated) usually means the carburetor is running too rich — fuel isn't burning completely. Replace the plug first with a fresh Champion RJ19LM, and if fouling returns within a few hours of run time, the carburetor is the real issue. Rich running also wastes fuel and reduces power, so a carburetor rebuild kit is the right next step.

How do I find my exact Stihl string trimmer model number for ordering parts?

The model number is stamped or printed on the trimmer shaft or near the fuel cap — look for "FS" followed by two or three digits (FS45, FS55, FS90, FS111, FS131). Enter that model number into the Repair Clinic lookup tool and you'll see every compatible part for your trimmer, from carburetors to grinding heads to fuel lines. Stihl parts are model-specific, so the correct number ensures you get the right fit first time.

Order Stihl String Trimmer Parts Online

Looking for genuine Stihl String Trimmer parts? Our online store provides a full range of high-quality replacement parts to keep your equipment running smoothly. Whether you need replacement weed eater parts or specific parts for string trimmer repair, we've got you covered. Enjoy the convenience of same-day shipping, ensuring that your parts arrive promptly and minimize downtime. Utilize our model number lookup tool to easily find compatible Stihl parts with a Price Match Guarantee. Plus, benefit from our No-Hassle 365-Day Returns policy, allowing you to return any uninstalled part within a year. If your string trimmer won't start or runs rough, consider replacing the spark plug, air filter, or cleaning the carburetor. For additional repair guidance, visit our String Trimmer Repair Help page. For a curated selection of Stihl parts, browse our Stihl String Trimmer Parts page for all your repair needs.

Stihl String Trimmer Model Number: Where to Look

Stihl prints the model number on a label or sticker attached to the shaft or engine housing of most string trimmers. Check near the fuel cap as well, and look for an "FS" designation followed by two or three digits, such as FS45, FS55, or FS111. Once you have the complete number, type it into our model number lookup and the catalog narrows to parts made for your unit. This filters the full Stihl string trimmer parts selection, including engine, fuel system, starter, handle, and trimmer head parts, to your exact model. You can then confirm compatibility before ordering and avoid sorting through parts that do not fit.