Quick answer: The Poulan Pro 42cc chainsaw is an affordable, entry-to-mid-level gas saw ideal for light-to-medium homeowner yard work, such as cutting firewood up to 14 inches in diameter and storm cleanup. Powered by a 42cc 2-stroke engine driving an 18-inch bar, it offers a great balance of power and value, though it requires strict fuel management and regular carb maintenance to perform at its best.
Engine Performance and Technical Specifications
At the core of the Poulan Pro 42cc platform is an air-cooled, two-stroke single-cylinder engine that delivers roughly 2.0 horsepower. Running at an operational speed near 9,000 RPM, this displacement provides sufficient chain speed to cut cleanly through hardwoods like oak and maple when paired with a sharp chain. The power plant utilizes Poulan’s OxyPower engine technology, which lowers exhaust emissions while maximizing fuel efficiency compared to older, non-regulated 2-stroke designs. Understanding these basic metrics helps you evaluate if the saw matches your woodcutting demands or if you should explore our chainsaw buying guides for larger timber operations.
Equipped factory-standard with an 18-inch guide bar, this unit runs a low-profile 3/8-inch pitch chain with a .050-inch gauge. This specific chain geometry minimizes engine drag, allowing the 42cc powerhead to maintain high revs even under load. The saw utilizes a standard centrifugal clutch system that engages the drive sprocket around 3,200 RPM, ensuring the chain remains completely stationary while the engine idles on the ground. Power delivery stays punchy across the mid-range throttle band, which helps prevent bogged cuts when bucking fallen logs.
Weight distribution plays a critical role in operator fatigue during extended cutting sessions. Stripped of fuel and chain oil, the powerhead weighs approximately 11.8 pounds, bringing the fully dressed working weight with a full tank of gas to just under 14 pounds. The integrated inertia-activated chain brake sits immediately in front of the wrap-around front handle, offering physical kickback protection compliant with ANSI B175.1 safety regulations.
| Specification | Poulan Pro 42cc (PR4218) Metric / Imperial Value |
|---|---|
| Engine Displacement | 42 cc (2.57 cu. in.) |
| Power Output | 1.5 kW / ~2.0 HP |
| Fuel Mixture Ratio | 50:1 (Gasoline to 2-Stroke Synthetic Oil) |
| guide bar length | 18 Inches (45 cm) — Accepts 16-Inch alternative |
| Chain Pitch & Gauge | 3/8" Low Profile (LP), .050" Gauge |
| Dry Weight (Powerhead Only) | 11.8 lbs (5.35 kg) |
Operation, Fueling, and Cold Start Best Practices
Operating a two-stroke engine safely requires precise fuel mixing to avoid catastrophic cylinder scoring. The Poulan Pro 42cc system calls for a strict 50:1 ratio of fresh, minimum 89-octane unleaded gasoline mixed with high-grade two-stroke air-cooled engine oil. Ethanolic fuel degrades small rubber engine components rapidly over time; using ethanol-free gas or adding a fuel stabilizer drastically extends the lifespan of the fuel lines and internal check valves. Proper lubrication extends beyond the gas tank—always fill your bar and chain oil reservoir using dedicated summer or winter grade bar oil whenever you refuel the machine.
Starting a cold Poulan Pro 42cc requires proper technique to prevent flooding the engine. Set the master switch to the ON position, press the purge bulb 6 to 8 times until clear fuel flows through the return line, and pull the choke lever fully out. Pull the starter rope firmly until the engine "pops" or briefly fires (typically within 3 to 5 pulls). Once you hear that initial firing attempt, push the choke lever halfway in or into the run position, then pull the starter cord again to start the engine. Squeezing the throttle trigger releases the high-idle latch and allows the engine to drop into a smooth, settled idle.
Pro tip: Brand-new drive chains experience severe initial stretch during their first 15–20 minutes under load due to friction heat and rivet seating. Always stop the saw after your first two test cuts in green wood, loosen the bar nuts slightly, and pull the tensioner until the drive lugs sit flush against the underside of the guide bar rail. Ignoring this initial thermal expansion often causes the chain to throw off the drive sprocket, damaging the drive links and side case cover.
Maintenance Essentials: Carburetor, Chains, and Filters
Keeping your saw performing predictably relies heavily on preventative maintenance. The air filtration system on the Poulan Pro 42cc uses a washable felt element designed to stop fine sawdust before it enters the intake tract. Clean this filter after every 5 tanks of fuel by tapping it lightly against a wooden block or washing it in warm, soapy water. Check out our detailed walkthrough on chainsaw maintenance protocols to ensure you never miss critical service windows that could cause premature engine wear.
The standard 3/8" LP .050" gauge chain requires routine sharpening with a standard 5/32-inch round file held at a strict 30-degree top-plate filing angle. cutting dirty wood or letting the bar nose touch soil will instantly dull the cutter edges, forcing you to apply excess downward pressure which overheats the guide bar rails. When replacing a worn cutter loop, verify your bar tail geometry to select the correct drive link count (typically 62 drive links for an 18-inch bar on this chassis).
Carburetor tuning issues represent the most common operational challenge for owners of budget gas chainsaws. The dual-needle Zama or Walbro diaphragm carburetors used on these 42cc engines feature high and low speed adjustment screws that control atmospheric metering. If the engine bogs down under load, dies at idle, or screams at excessively high RPMs when warm, the metering diaphragms may have hardened or the carburetor jetting may require fine adjustment using special pac-man or single-D carburetor tools. Inspect your spark plug every season; a light tan electrode indicates optimal combustion, while black oily deposits signal a rich mixture or excessive oil in your fuel blend.
| Specification | Detail |
|---|---|
| Engine | 42cc, 2-cycle gas |
| Bar length | 18 inches |
| Chain pitch | 3/8 inch |
| Chain gauge | .050 |
| Weight | ~13 lbs |
| Fuel mix | 40:1 or 50:1 (gas:oil) |
| Features | Anti-vibration, automatic chain oiler |
Common Troubleshooting and Repair Scenarios
When a Poulan Pro 42cc refuses to start, step one is diagnosing whether the issue stems from spark, fuel, or compression. Remove the Champion RCJ7Y (or equivalent NGK) spark plug and ground the threads against the cylinder head while pulling the rope to check for a bright blue spark. If no spark appears, inspect the stop switch wiring harness or replace the ignition coil module. If the plug comes out dripping wet with gasoline, the engine is flooded; clear the cylinder by removing the plug, turning the saw upside down, pulling the starter rope 10 times, and reassembling with a dry plug.
Loss of chain oiling is another common complaint on aged machines. The automatic oil pump drives off a worm gear located behind the clutch drum. If the chain runs dry despite a full oil reservoir, verify that the tiny oiler output port near the bar mounting studs isn't packed tightly with packed sawdust and chain oil sludge. Flushing the bar groove with a putty knife and flushing the oil tank with clean kerosene often clears stubborn blockages without needing a full teardown of the clutch assembly.
To assist in home repairs, consult the original exploded parts diagram to ensure correct component reassembly order. Key wear items that should be inspected annually include:
- Flexible Fuel Lines: Inspect for cracking, hardening, or collapse near the fuel tank grommet.
- Sprocket Drum & Clutch Bearing: Check for deep wear grooves caused by the drive links and grease the needle bearing.
- Bar Rails: Use a flat file to remove metal burrs forming along the top edge of the guide bar side rails.
- Anti-Vibration Buffers: Inspect the rubber isolators connecting the handle frame to the engine chassis for tears.
For residential users cutting 2 to 4 cords of firewood annually or clearing moderate storm debris, the Poulan Pro 42cc chainsaw provides dependable cutting performance at an affordable price point. Paired with fresh 50:1 premix fuel, proper safety gear including chaps and eye protection, and a sharp 5/32-inch file kept close by, this 42cc unit serves as a capable workhorse for your residential tree maintenance demands.
Frequently Asked Questions
What is the correct fuel mix ratio for the Poulan Pro 42cc chainsaw?
The Poulan Pro 42cc engine requires a precise 50:1 gas-to-oil mixture ratio using 89 octane or higher unleaded gasoline combined with high-grade 2-stroke air-cooled engine oil. Using ethanol-free fuel helps protect internal carburetor components.
What size file do I need to sharpen the stock Poulan Pro 42cc chain?
The factory 18-inch chain utilizes a 3/8-inch low-profile pitch with a .050-inch gauge, which requires a 5/32-inch (4.0mm) round chainsaw file held at a 30-degree sharpening angle.
Why does my Poulan Pro 42cc keep stalling when I pull the throttle?
Stalling under acceleration usually indicates a lean fuel mixture caused by a dirty air filter, cracked fuel lines, stale fuel, or a stiff diaphragm inside the carburetor that requires needle adjustment or a carburetor rebuild.
Can I put a 20-inch bar on my Poulan Pro 42cc saw?
While a 20-inch bar may physically bolt onto the chassis, it is not recommended. The 42cc engine performs best with a 16-inch or 18-inch bar; running a longer bar bogs down the motor and places excessive thermal strain on the engine clutch.
