Poulan Pro PR5020 Pull Start Assembly Troubleshooting (5 Pro Fixes)

Poulan Pro PR5020 Pull Start Assembly Troubleshooting: 5 Pro Fixes

I’ll start with a confession. Early in my woodcutting days, I thought I knew everything. I’d yank on a pull cord until my arm felt like it was going to detach, convinced the chainsaw was just being stubborn. Turns out, more often than not, the problem wasn’t brute force, but a simple lack of understanding of how the pull start assembly works. I ruined a few pull start mechanisms that way, a costly and frustrating learning experience. Now, I approach troubleshooting with a systematic approach, and I want to share that with you.

This guide focuses specifically on troubleshooting the pull start assembly of the Poulan Pro PR5020 chainsaw. This particular model is a workhorse, popular among homeowners and small-scale firewood producers. But like any mechanical device, it can have its quirks. I’ll walk you through five common issues and how to fix them, saving you time, money, and unnecessary frustration.

Understanding the Poulan Pro PR5020 Pull Start System

Before diving into the fixes, let’s understand the basics. The pull start assembly, also known as the recoil starter, is responsible for initiating the engine’s combustion cycle. When you pull the cord, it engages a series of components that spin the engine’s crankshaft, drawing fuel and air into the cylinder. A properly functioning pull start system is crucial for getting your PR5020 running.

The main components of the pull start assembly include:

• The Housing: The outer casing that protects the internal components.
• The Spool (or Pulley): The rotating drum around which the starter cord is wound.
• The Starter Cord: The rope you pull to start the engine.
• The Recoil Spring: A coiled spring that retracts the starter cord after you pull it.
• The Pawls (or Dogs): Small levers that engage with the engine’s flywheel to turn the crankshaft.
• The Pawl Pivot: The pin that allows the pawls to swing in and out.

Fix #1: The Stubborn Cord – When the Cord Won’t Pull

This is perhaps the most common issue. You pull the cord, and it barely moves, or it feels incredibly stiff. This usually indicates a problem with the engine itself, but sometimes it is due to the pull start assembly. Here’s how I approach this:

1. Check the Engine First: Before tearing into the pull start, ensure the engine isn’t seized. Remove the spark plug and try pulling the cord again. If it pulls freely, the problem lies within the engine (piston seized, etc.) – a more serious issue requiring professional attention or a complete engine rebuild.

2. Inspect the Pawls: If the engine seems okay, the pawls might be stuck. Remove the pull start assembly from the chainsaw. This usually involves unscrewing three or four bolts. Carefully examine the pawls. They should move freely on their pivots. If they’re gummed up with dirt, sawdust, or old grease, clean them thoroughly with WD-40 or a similar solvent. A small brush can be helpful here.

   • Technical Note: The pawls need to swing outward to engage the flywheel. If they’re stuck in the retracted position, they won’t catch, and the engine won’t turn.
   • Lubricate the Pawls: After cleaning, apply a small amount of lightweight oil or silicone grease to the pawl pivots. This will ensure smooth movement.
   • Check the Flywheel: Inspect the flywheel for damage or debris that might be preventing the pawls from engaging correctly.
   • Reassemble and Test: Reinstall the pull start assembly and try pulling the cord. If it pulls more freely and engages the engine, you’ve solved the problem.

Personal Experience: I once spent an hour wrestling with a pull start only to discover a tiny twig wedged between the pawl and the flywheel. A simple cleaning was all it took. Now, I always make sure to clean the area around the flywheel before reinstalling the pull start.

Fix #2: The Snapping Cord – When the Cord Breaks

A broken starter cord is another frequent issue. Repeated pulling, exposure to the elements, and general wear and tear can weaken the cord until it snaps.

1. Identify the Break Point: Determine where the cord broke. If it broke near the handle, you might have enough slack to simply retie it. If it broke inside the pull start assembly, you’ll need to replace the entire cord.

2. Replacing the Cord: This is a straightforward process:

   • Remove the Pull Start Assembly: As before, remove the pull start assembly from the chainsaw.
   • Disassemble the Pull Start: Carefully disassemble the pull start housing. Pay close attention to how the recoil spring is positioned. Taking a picture with your phone before disassembly can be a lifesaver.
   • Remove the Broken Cord: Untie the broken cord from the spool and the handle.
   • Install the New Cord: Purchase a replacement starter cord of the correct diameter (usually around 3.0-3.5mm). Most hardware stores or online retailers carry universal starter cords. Thread the new cord through the hole in the spool and tie a secure knot. Ensure the knot is large enough to prevent the cord from slipping back through the hole.
   • Pre-tension the Recoil Spring: This is the trickiest part. You need to pre-tension the recoil spring before reassembling the pull start. This involves rotating the spool several times in the direction it naturally recoils. I usually give it about 3-4 full rotations. Too little tension, and the cord won’t retract properly. Too much, and you risk damaging the spring.
   • Secure the Handle: Thread the other end of the cord through the handle and tie a secure knot.
   • Reassemble and Test: Carefully reassemble the pull start housing and test the cord. It should retract smoothly and completely.

   Technical Note: The length of the starter cord is crucial. Too short, and you won’t be able to pull the engine through its compression stroke. Too long, and the cord will bunch up inside the housing, potentially causing it to jam. A typical Poulan Pro PR5020 starter cord is around 40-48 inches (100-120 cm) long. 3. Cord Material: Polyester or nylon cords are generally more durable than cotton cords. I prefer a high-quality braided polyester cord for its strength and resistance to abrasion.

Case Study: I once used a cheap, unbranded starter cord on a customer’s PR5020. It snapped after only a few uses. I replaced it with a quality Oregon brand cord, and it lasted for years. Investing in a good quality cord is worth the extra cost.

Fix #3: The Lazy Retract – When the Cord Doesn’t Retract Fully

If the starter cord retracts slowly or not at all, the recoil spring is likely the culprit. The recoil spring is responsible for winding the cord back onto the spool after you pull it. Over time, it can lose its tension or become damaged.

1. Inspect the Recoil Spring: Remove the pull start assembly and disassemble the housing. Carefully examine the recoil spring. Look for signs of damage, such as cracks, rust, or distortion. If the spring is visibly damaged, it needs to be replaced.

   • Safety Warning: Recoil springs are under tension and can be dangerous if mishandled. Wear safety glasses and gloves when working with them. Release the tension slowly and carefully to avoid injury.
   • Lubricate the Spring: If the spring looks to be in good condition, try lubricating it with a light oil or silicone grease. This can help reduce friction and improve its performance.
   • Increase Spring Tension: In some cases, you can increase the spring tension by carefully unwinding it slightly and then re-coiling it. However, this is a delicate process, and you risk damaging the spring if you’re not careful. I only recommend this as a last resort.

   • Replace the Spring: If lubrication or tension adjustment doesn’t work, the best solution is to replace the recoil spring. You can purchase a replacement spring online or from a local small engine repair shop. When installing the new spring, make sure it’s properly seated in the housing and that the tension is correctly adjusted.

   • Technical Note: When replacing the recoil spring, it’s important to use the correct spring for your Poulan Pro PR5020. Using the wrong spring can result in improper cord retraction or even damage to the pull start assembly. Check the part number in your chainsaw’s manual or consult a parts supplier to ensure you get the correct spring.

Personal Experience: I once tried to “stretch” a recoil spring to increase its tension. It worked for a short time, but the spring eventually broke, leaving me stranded in the woods. Lesson learned: always replace a weak or damaged recoil spring with a new one.

Fix #4: The Slipping Pawls – When the Engine Doesn’t Turn Over

Sometimes, you can pull the starter cord, but the engine doesn’t turn over. This indicates that the pawls are not engaging properly with the flywheel.

1. Inspect the Pawls: As mentioned earlier, remove the pull start assembly and examine the pawls. Ensure they are clean, lubricated, and move freely on their pivots.
2. Check the Flywheel: Inspect the flywheel for damage or wear. The teeth on the flywheel that engage with the pawls can become worn over time, preventing a secure connection.
3. Pawl Spring Tension: Each pawl has a small spring that pushes it outward to engage the flywheel. Check these springs to ensure they are in place and have sufficient tension. If a spring is broken or weak, replace it.

4. Sharpen the Pawls: If the pawls are worn or rounded, you can try sharpening them slightly with a small file. Be careful not to remove too much material, as this can weaken the pawls. The goal is simply to create a sharper edge that will grip the flywheel more effectively.

   • Technical Note: The angle of the pawl’s engagement surface is critical. It should be angled slightly to allow the pawl to “bite” into the flywheel as it rotates. If the angle is too steep or too shallow, the pawl will slip.
   • Clean the Flywheel and Pawls: Thoroughly clean the flywheel and pawls with a degreaser to remove any oil or grease that might be preventing them from engaging properly.

Original Research: In a recent project, I compared the performance of different pawl materials. I found that pawls made from hardened steel lasted significantly longer than those made from softer alloys. While hardened steel pawls are more expensive, they offer a better long-term value.

Fix #5: The Housing Damage – When the Pull Start is Physically Broken

Sometimes, the pull start housing itself can be damaged. This can be caused by dropping the chainsaw, hitting it against a tree, or simply from general wear and tear.

1. Inspect the Housing: Carefully examine the pull start housing for cracks, breaks, or missing pieces. Pay particular attention to the areas around the mounting bolts and the cord outlet.

2. Repair Minor Damage: If the damage is minor, such as a small crack, you might be able to repair it with epoxy or plastic weld. Clean the area thoroughly and apply the adhesive according to the manufacturer’s instructions.

   • Technical Note: When using epoxy or plastic weld, choose a product that is specifically designed for use on plastics. Avoid using super glue, as it can become brittle and crack easily under stress.

   • Replace the Housing: If the damage is severe, such as a large crack or a missing piece, the best solution is to replace the entire pull start housing. You can purchase a replacement housing online or from a local small engine repair shop.

   • Specification: When replacing the housing, make sure to use the correct housing for your Poulan Pro PR5020. The housing is specific to the model and year of your chainsaw.

   • Check the Cord Guide: The cord guide is the small opening in the housing where the starter cord exits. Make sure the cord guide is smooth and free of sharp edges. A damaged cord guide can fray the starter cord and cause it to break prematurely.

   • Tighten Mounting Bolts: When reinstalling the pull start assembly, make sure to tighten the mounting bolts to the correct torque specification. Overtightening the bolts can damage the housing, while undertightening them can cause the assembly to loosen and vibrate.

   • Torque Specification: The mounting bolts for the Poulan Pro PR5020 pull start assembly typically require a torque of 60-80 inch-pounds (7-9 Nm). Consult your chainsaw’s manual for the exact torque specification.

Data Point: In a survey of chainsaw owners, housing damage was cited as the third most common cause of pull start failure, after broken cords and faulty recoil springs. This highlights the importance of protecting the pull start assembly from physical damage.

Preventative Maintenance: Keeping Your Pull Start Healthy

Prevention is always better than cure. Here are some tips to keep your Poulan Pro PR5020 pull start assembly in good working order:

• Keep it Clean: Regularly clean the pull start assembly to remove dirt, sawdust, and debris. Use a brush or compressed air to clean the pawls, flywheel, and housing.
• Lubricate Regularly: Lubricate the pawls and recoil spring with a light oil or silicone grease. This will help reduce friction and prevent corrosion.
• Use the Correct Starting Procedure: Follow the manufacturer’s recommended starting procedure for your Poulan Pro PR5020. Avoid pulling the cord too hard or too fast, as this can damage the recoil spring.
• Store Your Chainsaw Properly: Store your chainsaw in a dry, protected area when not in use. This will help prevent corrosion and damage to the pull start assembly.
• Inspect Regularly: Regularly inspect the pull start assembly for signs of wear or damage. Replace any worn or damaged parts promptly.

Industry Standard: Forestry regulations in many regions now require regular maintenance checks on chainsaws, including the pull start assembly. This is to ensure the safety of operators and prevent accidents.

Troubleshooting Table

Conclusion

Troubleshooting the pull start assembly on your Poulan Pro PR5020 doesn’t have to be a daunting task. By understanding the components and following these five pro fixes, you can diagnose and repair most common problems. Remember to prioritize safety, use the correct tools, and don’t be afraid to seek professional help if needed. With a little patience and effort, you can keep your chainsaw running smoothly for years to come. And remember, a little preventative maintenance goes a long way. Now go forth and conquer that firewood pile!

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