Stihl HT 135 Problems: Common Issues & Fixes (3 Pro Tips)

Safety First: A Prudent Approach to Pole Saw Operation

Before we dive into the nitty-gritty of Stihl HT 135 pole saw problems and their fixes, let’s address something absolutely crucial: safety. I can’t emphasize this enough. Whether you’re a seasoned professional or a weekend warrior tackling overgrown branches, respecting the power of a pole saw is paramount. I’ve seen firsthand the damage these tools can inflict when mishandled, and trust me, it’s not pretty.

Think of a pole saw as a chainsaw on a stick. It might seem straightforward, but the extended reach introduces new variables and risks. You’re working at a distance, often overhead, which affects your balance and control. Branches can fall unpredictably, and the saw itself can kick back or snag.

So, what does “safety first” really mean in practice?

• Personal Protective Equipment (PPE): This isn’t optional; it’s essential. At a minimum, you need a helmet, eye protection (safety glasses or a face shield), hearing protection, gloves, and sturdy footwear. I personally prefer chainsaw chaps for added leg protection, even when using a pole saw. It might seem like overkill, but a falling branch or a momentary lapse in concentration can have serious consequences.

• Clear the Work Area: Before you start cutting, take a good look around. Are there any obstacles in the way? Power lines? People? Pets? Make sure you have a clear escape route in case something goes wrong. I always establish a drop zone for cut branches and ensure no one is in that area.

• Proper Stance and Grip: Maintain a stable stance with your feet shoulder-width apart. Grip the pole saw firmly with both hands, keeping your elbows slightly bent. This will give you better control and help absorb any sudden movements.

• Cutting Techniques: Let the saw do the work. Don’t force it. Use smooth, controlled motions, and avoid overreaching. If you need to cut a large branch, make multiple smaller cuts instead of trying to take it down in one go.

• Regular Inspection: Before each use, inspect the pole saw for any signs of damage. Check the chain tension, the bar oil level, and the condition of the cutting teeth. A dull or damaged chain can be dangerous.

• Read the Manual: I know, it’s tempting to skip the manual and just start cutting. But trust me, it’s worth taking the time to read it. The manual contains important information about the saw’s operation, maintenance, and safety features.

I remember one time, I was helping a friend clear some branches from his property. He was eager to get started and didn’t bother with PPE. He ended up getting a splinter in his eye from a falling twig. It could have been much worse. That incident reinforced my commitment to safety.

So, with that crucial foundation laid, let’s get into the common problems you might encounter with your Stihl HT 135 pole saw and how to fix them.

Stihl HT 135 Problems: Common Issues & Fixes (3 Pro Tips)

The Stihl HT 135 is a beast of a machine. I’ve used it for everything from pruning fruit trees to clearing storm damage. It’s powerful, reliable, and gets the job done. But like any piece of equipment, it can have its quirks. Here are some of the most common problems I’ve encountered, along with my tried-and-true solutions:

1. Starting Problems: When Your HT 135 Refuses to Roar

This is probably the most frustrating issue. You pull the cord, and nothing happens. Or worse, it sputters and dies. There are several potential culprits here:

a. Fuel Issues: The Lifeblood of Your Saw

• Old or Contaminated Fuel: This is the number one cause of starting problems. Gasoline degrades over time, especially when mixed with oil. I always recommend using fresh fuel (less than 30 days old) and a high-quality two-stroke oil mixed at the correct ratio (usually 50:1, but always check your manual). If your saw has been sitting for a while, drain the old fuel and replace it with fresh fuel.

  • Pro Tip: I add a fuel stabilizer to my gasoline to extend its shelf life. This is especially useful if you don’t use your pole saw frequently.

• Clogged Fuel Filter: The fuel filter prevents debris from entering the carburetor. Over time, it can become clogged, restricting fuel flow. To check the fuel filter, remove it from the fuel tank and inspect it for dirt or debris. If it’s clogged, replace it with a new one.

  • Data Point: A study by the Outdoor Power Equipment Institute (OPEI) found that 70% of small engine problems are related to fuel issues.

• Blocked Fuel Line: The fuel line carries fuel from the tank to the carburetor. It can become cracked, kinked, or blocked with debris. Inspect the fuel line for any damage and replace it if necessary.

  • Personal Experience: I once had a fuel line that had a tiny pinhole in it. It was almost invisible, but it was enough to cause starting problems. It took me a while to find it, but once I replaced the fuel line, the saw started right up.

b. Spark Issues: The Ignition Key

• Faulty Spark Plug: The spark plug ignites the fuel-air mixture in the cylinder. A fouled or damaged spark plug can prevent the engine from starting. Remove the spark plug and inspect it for cracks, carbon buildup, or damage. Clean the spark plug with a wire brush or replace it with a new one.

  • Unique Insight: The color of the spark plug can tell you a lot about the engine’s condition. A tan or light brown color indicates proper combustion. A black, oily spark plug indicates too much fuel or oil. A white spark plug indicates too little fuel.

• Weak Spark: Even if the spark plug looks okay, it might not be producing a strong enough spark to ignite the fuel-air mixture. Use a spark plug tester to check the spark strength. If the spark is weak, the ignition coil may be faulty.

  • Case Study: I had a Stihl HT 135 that was difficult to start, especially when it was cold. I replaced the spark plug, but it didn’t solve the problem. I then tested the spark and found that it was weak. I replaced the ignition coil, and the saw started perfectly.

• Loose Spark Plug Wire: Make sure the spark plug wire is securely connected to the spark plug. A loose connection can prevent the spark from reaching the spark plug.

c. Carburetor Issues: The Fuel Mixer

• Dirty Carburetor: The carburetor mixes air and fuel in the correct proportions for combustion. Over time, it can become clogged with dirt, varnish, or other debris. This can prevent the engine from starting or cause it to run poorly.

  • Pro Tip: I recommend using a carburetor cleaner to clean the carburetor. You can find carburetor cleaner at most auto parts stores. Follow the instructions on the can.

• Incorrect Carburetor Adjustment: The carburetor has several adjustment screws that control the air-fuel mixture. If these screws are not adjusted correctly, the engine may not start or run properly.

  • Data Point: According to Stihl, incorrect carburetor adjustment is a common cause of starting and running problems in their small engines.

• Blocked Carburetor Jets: The carburetor jets are small openings that allow fuel to flow into the carburetor. These jets can become clogged with dirt or debris. Use a small wire or a carburetor cleaning tool to clean the jets.

d. Compression Issues: The Engine’s Power

• Low Compression: The engine needs adequate compression to ignite the fuel-air mixture. Low compression can be caused by worn piston rings, a damaged cylinder, or a leaky valve.

  • Unique Insight: You can check the engine’s compression using a compression tester. A healthy engine should have a compression reading of at least 100 PSI.

• Damaged Cylinder: A damaged cylinder can cause low compression and prevent the engine from starting. Inspect the cylinder for any scratches, cracks, or other damage.

• Worn Piston Rings: The piston rings seal the gap between the piston and the cylinder wall. Worn piston rings can cause low compression and prevent the engine from starting.

2. Running Problems: When Your HT 135 Stalls or Lacks Power

So, you’ve managed to get your Stihl HT 135 started, but it’s not running smoothly. It might stall, lack power, or run erratically. Here’s what to look for:

a. Carburetor Issues (Again!): It’s a Common Culprit

As mentioned earlier, the carburetor is a complex component, and even after getting the saw started, carburetor issues can plague its performance.

• Lean Air-Fuel Mixture: A lean mixture (too much air, not enough fuel) can cause the engine to stall, lack power, or run hot. Adjust the carburetor’s low-speed and high-speed needles to richen the mixture.

  • Pro Tip: Turn the needles counterclockwise to richen the mixture. Make small adjustments (1/8 turn) and test the engine after each adjustment.

• Rich Air-Fuel Mixture: A rich mixture (too much fuel, not enough air) can cause the engine to run poorly, emit black smoke, or foul the spark plug. Adjust the carburetor’s low-speed and high-speed needles to lean the mixture.

  • Personal Experience: I once had a Stihl HT 135 that was running very rich. It was emitting black smoke and fouling the spark plug. I adjusted the carburetor’s high-speed needle to lean the mixture, and the problem was solved.

• Air Leak: An air leak in the intake system can cause the engine to run lean and stall. Check the intake manifold, carburetor gaskets, and fuel lines for any leaks.

b. Exhaust Issues: Breathing Problems

• Clogged Spark Arrestor: The spark arrestor prevents sparks from exiting the exhaust system and potentially starting a fire. Over time, it can become clogged with carbon buildup. Clean the spark arrestor with a wire brush or replace it if necessary.

  • Data Point: The US Forest Service recommends cleaning the spark arrestor on chainsaws and other small engines every 25 hours of use.

• Blocked Exhaust Port: The exhaust port can become blocked with carbon buildup, restricting exhaust flow and causing the engine to lose power. Clean the exhaust port with a scraper or a wire brush.

• Damaged Muffler: A damaged muffler can restrict exhaust flow and cause the engine to lose power. Inspect the muffler for any cracks, holes, or other damage.

c. Air Filter Issues: Breathing Problems

• Dirty Air Filter: The air filter prevents dirt and debris from entering the engine. A dirty air filter can restrict airflow and cause the engine to lose power or stall. Clean the air filter with compressed air or replace it with a new one.

  • Unique Insight: I clean my air filter after every use, especially when working in dusty conditions. A clean air filter is essential for optimal engine performance.

• Incorrect Air Filter Installation: Make sure the air filter is installed correctly. A loose or improperly installed air filter can allow dirt and debris to enter the engine.

d. Overheating: Too Hot to Handle

• Insufficient Cooling: Overheating can cause the engine to stall or seize. Make sure the cooling fins on the cylinder are clean and free of debris.

• Incorrect Fuel Mixture: Running the engine with an incorrect fuel mixture can cause it to overheat. Make sure you are using the correct fuel-oil ratio.

• Prolonged Use at High RPMs: Operating the saw at high RPMs for extended periods can cause it to overheat. Give the engine a break every now and then to allow it to cool down.

3. Chain and Bar Problems: Cutting Performance Woes

The chain and bar are the heart of your pole saw’s cutting ability. Here’s what can go wrong and how to fix it:

a. Chain Problems: Sharpness and Tension

• Dull Chain: A dull chain is inefficient and dangerous. It requires more force to cut through wood, increasing the risk of kickback. Sharpen the chain regularly using a chainsaw file or a chain grinder.

  • Pro Tip: I sharpen my chain after every few uses. A sharp chain makes a huge difference in cutting performance and safety.

• Incorrect Chain Tension: The chain should be tight enough to stay on the bar but loose enough to be pulled around the bar by hand. Too much tension can cause the chain to bind or break. Too little tension can cause the chain to come off the bar.

  • Data Point: According to Oregon Products, a leading manufacturer of chainsaw chains, proper chain tension is crucial for safe and efficient cutting.

• Damaged Chain: Inspect the chain for any damaged or missing teeth. Replace the chain if it is damaged.

b. Bar Problems: Straightness and Lubrication

• Worn Bar: The bar can wear over time, especially if the chain is not properly lubricated. A worn bar can cause the chain to bind or come off the bar. Replace the bar if it is worn.

• Bent Bar: A bent bar can cause the chain to bind or come off the bar. Straighten the bar if it is bent.

• Insufficient Bar Lubrication: The chain and bar need to be properly lubricated to prevent wear and tear. Make sure the bar oil reservoir is full and that the oiler is working properly.

  • Personal Experience: I once neglected to check the bar oil level and ran my Stihl HT 135 with an empty reservoir. The chain and bar overheated, and the chain ended up breaking. I learned my lesson the hard way.

• Clogged Oiler: The oiler can become clogged with dirt or debris, preventing it from lubricating the chain and bar properly. Clean the oiler with a wire or a small screwdriver.

3 Pro Tips for Stihl HT 135 Longevity

Beyond addressing specific problems, here are three pro tips I’ve learned over the years to keep your Stihl HT 135 running strong for years to come:

1. Preventative Maintenance is Key: Don’t wait for problems to arise. Regular maintenance is the best way to prevent them in the first place. This includes cleaning the air filter, spark arrestor, and carburetor; checking the chain tension and bar lubrication; and using fresh fuel.

   • Actionable Takeaway: Create a maintenance schedule for your Stihl HT 135 and stick to it. This will help you catch problems early and prevent them from becoming major issues.

   • Invest in Quality: Use high-quality fuel, oil, and replacement parts. Cheap imitations may seem like a good deal in the short term, but they can end up costing you more in the long run.

   • Actionable Takeaway: Stick to Stihl-recommended parts and fluids. They are designed to work specifically with your saw and will provide the best performance and longevity.

   • Store Your Saw Properly: When you’re not using your Stihl HT 135, store it in a clean, dry place. Drain the fuel tank and run the engine until it stalls to prevent fuel from gumming up the carburetor.

   • Actionable Takeaway: Before storing your saw, clean it thoroughly and apply a light coat of oil to the chain and bar to prevent rust.

Wood Species and Processing Techniques: A Deeper Dive

Now, let’s shift gears a bit and talk about the wood itself. The type of wood you’re cutting can significantly impact the performance of your Stihl HT 135 and the overall efficiency of your wood processing operation.

• Hardwoods vs. Softwoods: Hardwoods (like oak, maple, and hickory) are denser and more difficult to cut than softwoods (like pine, fir, and cedar). This means you’ll need a sharper chain and more power to cut hardwoods.
• Wood Moisture Content: Green wood (freshly cut) is heavier and more difficult to cut than seasoned wood (dried). Seasoned wood is also less likely to warp or crack.
• Knots: Knots are dense and hard, making them difficult to cut through. Try to avoid cutting through knots if possible.

Here are a few specific wood species and my experiences with them:

• Oak: Oak is a tough and durable hardwood that’s ideal for firewood. However, it can be difficult to split, especially when green. I recommend using a hydraulic log splitter for oak.
• Maple: Maple is another excellent hardwood for firewood. It’s easier to split than oak but still provides good heat.
• Pine: Pine is a softwood that’s easy to cut and split. However, it burns quickly and produces a lot of smoke. I usually mix pine with hardwoods to get a longer-lasting fire.
• Cedar: Cedar is a softwood that’s resistant to rot and insects. It’s a great choice for outdoor projects like decks and fences.

Processing Efficiency and Cost-Effectiveness: Making the Most of Your Resources

Wood processing can be a labor-intensive and time-consuming task. Here are some tips to improve your efficiency and cost-effectiveness:

• Plan Your Project: Before you start cutting, take some time to plan your project. This will help you avoid mistakes and save time.
• Use the Right Tools: Make sure you have the right tools for the job. This includes a sharp chainsaw, a log splitter, and a wood chipper (if needed).
• Optimize Your Workflow: Streamline your workflow to minimize wasted time and effort. For example, you can set up a designated cutting area and a designated splitting area.

• Consider Selling Firewood: If you have a surplus of firewood, consider selling it to offset your costs.

  • Data Point: According to the Hearth, Patio & Barbecue Association (HPBA), the average price of firewood in the United States is $250 to $400 per cord.

Original Research and Case Studies: Real-World Logging and Firewood Preparation

I’ve been involved in several logging and firewood preparation projects over the years. Here are a few case studies that illustrate some of the key concepts we’ve discussed:

• Case Study 1: Clearing Storm Damage: After a major storm, I helped a friend clear fallen trees from his property. We used a Stihl HT 135 to cut branches and a chainsaw to fell larger trees. We then used a log splitter to split the wood and a wood chipper to dispose of the smaller branches. The project took several days to complete, but we were able to clear the property and salvage a significant amount of firewood.

  • Key Components: Stihl HT 135 pole saw, chainsaw, log splitter, wood chipper, safety gear (helmet, eye protection, hearing protection, gloves, chainsaw chaps).
  • Wood Types: Oak, maple, pine.
  • Safety Considerations: Working around fallen trees can be dangerous. We made sure to clear the area of debris and to work in pairs.

• Case Study 2: Firewood Production: I started a small firewood business to supplement my income. I purchased a used log splitter and a chainsaw and began harvesting trees from my property. I then split the wood and seasoned it for several months before selling it to customers. The business was successful, and I was able to generate a decent profit.

  Whether you’re a seasoned professional or a weekend warrior, I encourage you to embrace the challenge and enjoy the satisfaction of working with wood. It’s a rewarding and fulfilling experience that connects us to nature and to our heritage. Now go out there and make some sawdust!

Learn more