Polaris Sportsman 570 Fuel Pump: Your Complete Guide to Issues, Replacement, and Maintenance

If your Polaris Sportsman 570 is hard to start, sputtering under load, or won't run at all, a failing fuel pump is a prime suspect. This critical component delivers gasoline from the tank to the engine under precise pressure. Understanding how it works, recognizing signs of failure, knowing how to replace it, and performing proper maintenance is essential for keeping your Sportsman 570 running reliably for years. Neglecting fuel pump issues can lead to frustrating breakdowns and expensive repairs down the line.

(Understanding the Heart of the Fuel System)

The fuel pump on your Sportsman 570 is an electric, in-tank submersible pump. Located inside the fuel tank, it operates submerged in gasoline, which helps cool and lubricate its internal components. When you turn the ignition key or press the start button, the Electronic Control Module (ECM) sends power to the pump. It rapidly pressurizes the fuel system, sending gasoline through the fuel line and fuel filter up to the fuel rail and injectors. Maintaining the correct fuel pressure (typically around 3.8 PSI on a healthy Sportsman 570 system at idle) is absolutely vital. Precise pressure ensures the fuel injectors can atomize the fuel correctly, creating the optimal air-fuel mixture for efficient combustion. Without consistent pressure, engine performance suffers dramatically.

(Spotting the Warning Signs of Fuel Pump Failure)

A weakening or failed Polaris Sportsman 570 fuel pump announces itself through distinct symptoms. Pay close attention to these warning signs:

• Difficult Starting or Extended Cranking: The most common early sign. The engine cranks over fine but refuses to start promptly, or takes significantly longer than usual. This happens because the pump struggles to build adequate pressure initially.
• Engine Sputtering, Stumbling, or Loss of Power Under Load: As you accelerate, climb hills, or pull a load, the engine demands more fuel. A failing pump cannot meet this increased demand, causing noticeable hesitation, misfires, jerking, or a sudden drop in power.
• Engine Stalling: Especially noticeable when the engine is hot or under sustained load. Lack of sufficient fuel pressure causes the engine to abruptly cut out. It might restart after cooling down slightly, only to stall again later.
• No-Start Condition: The most severe symptom. You hear the starter engage normally, but the engine shows no sign of firing. Often accompanied by a silent hum or buzz from under the seat area instead of the usual pump priming sound when you turn the key on (before starting). A complete lack of the priming sound is a major red flag.
• Check Engine Light (CEL) Illumination: While not always triggered by pump failure alone, a weak pump can cause lean running conditions or misfires, potentially setting Diagnostic Trouble Codes (DTCs) like P0171 (System Too Lean) or P0231 (Fuel Pump Secondary Circuit Low). Use a compatible OBD-II scanner to read these codes if the CEL is on.

(Why Fuel Pumps Fail in the Sportsman 570)

Understanding the common causes of fuel pump failure helps in prevention:

• Contaminated Fuel: Dirt, debris, water, or rust particles entering the tank are a major killer. These particles gradually erode the pump's internal components or jam its tiny internal workings. Contamination often originates from old gasoline, using dirty funnels, or a deteriorating fuel tank.
• Running on Low Fuel: Consistently operating with the fuel level below 1/4 tank is detrimental. Submersible pumps rely on fuel for cooling. Low fuel levels cause the pump to run hotter, significantly shortening its lifespan and increasing wear. Overheating is a primary cause of premature failure.
• Using Old or Improper Fuel: Gasoline degrades over time (typically within 30-60 days). Stale fuel forms varnishes and gums that clog the pump inlet strainer and filter, forcing the pump to work harder and wear out faster. Using fuel with too high ethanol content without appropriate additives can also be problematic.
• Electrical Issues: Problems within the pump's power circuit – such as corroded connectors, damaged wiring harnesses (vibration or rodent damage), blown fuses (the Sportsman 570 often uses a 15A fuse, check your owner's manual or fuse box diagram), or a failing relay – can prevent the pump from receiving adequate power. Even low voltage due to a weak battery or poor connections can stress the pump motor. Locate your main fuse box and the fuel pump fuse/relay.
• Normal Wear and Tear: Like any mechanical/electrical device, internal seals wear out and motors eventually fail after thousands of hours of operation. Most OEM fuel pumps offer reliable service for many years with proper care.

(Confirming Fuel Pump Problems Before Spending)

Before spending money on a new pump, perform these critical checks to verify the issue truly originates from the fuel pump or its circuitry:

1. Verify the Obvious: Ensure the ATV has sufficient fuel! Check the gauge visually if possible, but don't fully trust it. Cycle the ignition key on and off a few times and listen carefully near the fuel tank under the seat. You should hear a distinct humming or buzzing sound for about 2-5 seconds as the pump primes the system. NO SOUND is a strong indicator of a pump or circuit failure. Be aware of other safety noises your ATV might make.
2. Check Fuses and Relays: Locate the main fuse box (consult your owner's manual or parts diagram). Find the fuse specifically labeled for the fuel pump (typically 15A on Sportsman 570 models). Remove it and inspect for a broken filament. Test the fuse with a multimeter (continuity setting) or visually confirm the fuse wire is intact. Also, locate the fuel pump relay. Swapping it with a known identical relay (like the fan relay or starter relay, if compatible - check your manual first) can rule out a bad relay. Listen again for the pump prime sound after relay swap.
3. Inspect Electrical Connections: Trace the wiring from the fuel tank harness connector towards the main wiring harness. Disconnect connections (with battery disconnected first for safety). Look for corrosion (green/white powdery substance), bent pins, loose terminals, or melted plastic. Clean corrosion carefully with electrical contact cleaner and a soft brush. Ensure connectors click firmly back together.
4. Perform Fuel Pressure Test: This is the most definitive test for pump health. You'll need a dedicated fuel pressure test kit compatible with small engines (check fitting sizes - Polaris often uses a Schrader valve test port). Locate the Schrader valve (looks like a tire valve stem) usually found on the fuel rail or fuel line near the throttle body. Safely relieve residual pressure. Connect the pressure gauge. Turn the ignition key to "ON" (do not start engine). Observe the pressure reading. It should rapidly build to approximately 3.8 - 4.0 PSI (confirm spec in your service manual) and HOLD that pressure steady when the pump stops priming. If pressure is low or takes too long to build, or bleeds down rapidly, the pump, filter, or pressure regulator is faulty. If no pressure builds and you hear the pump running, suspect a severe blockage or leak. Pressure below 3.0 PSI often indicates pump failure. Pressure dropping quickly after priming points to a bad internal check valve in the pump or a leaking injector/regulator.

(Selecting a Replacement Polaris Sportsman 570 Fuel Pump)

Choosing the right replacement is crucial. You have three main options:

1. OEM (Original Equipment Manufacturer) Pumps:
   • Pros: Guaranteed exact fit, performance, and longevity designed specifically for your Sportsman 570. Highest quality standards.
   • Cons: Most expensive option. The genuine Polaris part number is often something like 4012941 (ALWAYS double-check with your VIN at a dealer parts counter or reliable online parts diagrams).
2. High-Quality Aftermarket Pumps:
   • Pros: Offer comparable quality and reliability to OEM at a significantly lower cost. Reputable brands often use the same quality materials and specifications. Look for brands with strong industry reputations specifically for ATV fuel pumps.
   • Cons: Research is crucial to avoid cheap knock-offs. Ensure compatibility with your exact model year (e.g., 2011 Polaris Sportsman 570 HO X2 vs. 2017 Polaris Sportsman 570).
3. Cheap Aftermarket/Economy Pumps:
   • Pros: Extremely low price point.
   • Cons: Severely compromised reliability and lifespan. Prone to premature failure due to inferior materials and construction. Notorious for causing frustrating repeat breakdowns. Generally NOT recommended for a critical component like the fuel pump.

Completeness Matters: When purchasing, decide between:

• Complete Fuel Pump Module Assembly: Includes the pump, pre-pump strainer sock, fuel level sending unit, module housing, locking ring, and often new seals/gaskets. This is often the best choice, as it replaces aging components prone to failure (like the sending unit) and ensures compatibility. Recommended for DIY unless the original module housing is pristine.
• Pump Element Only: Just the bare pump motor itself. Requires transferring all the other components (strainer, float arm, etc.) from your old module housing, demanding more disassembly precision. Only recommended if your module housing and level sender are in perfect condition. Mistakes transferring parts can lead to leaks.

Where to Buy: Order from reputable ATV parts suppliers, authorized Polaris dealers, or established online retailers known for powersports parts. Verify exact model year compatibility.

(Step-by-Step DIY Polaris Sportsman 570 Fuel Pump Replacement (Approx. Time: 1-2.5 Hours))

Disclaimer: Working on fuel systems requires extreme caution. Fumes are highly flammable. Work outdoors or in a well-ventilated area away from sparks/flames. Disconnect the battery negative (-) terminal first. Wear safety glasses and gloves. If you are uncomfortable with mechanical repairs, seek professional service. Always consult the official service manual for your specific model year and ATV variant (e.g., EPS model) for precise procedures and torque specs. Some steps vary slightly.

Tools Needed: Socket set (metric), wrenches, fuel line disconnect tools (specific to your fuel line type - often quick-disconnect style and sometimes smaller for vapor lines), needle-nose pliers, flat-head screwdriver, shop towels, drain pan, new replacement pump assembly (complete module is easiest), replacement fuel line o-rings (if your kit doesn't include them), replacement gasket for fuel pump access cover (if applicable/available).

Procedure:

1. Preparation & Safety:

   • Park on level ground, engine COOL. Place transmission in Park. Set parking brake.
   • DISCONNECT THE NEGATIVE (-) BATTERY TERMINAL.
   • Relieve fuel pressure by removing the fuel tank cap and leaving it off.
   • Locate the main fuse box and remove the fuel pump fuse (prevents accidental activation).
   • Open the rear seat cover. Carefully clean any debris around the fuel pump access panel (usually a large round or rectangular cover under the rear seat/bed area). If your model lacks an access panel (some early 570s didn't), the entire rear cargo box/bed likely needs removal, which is more involved.

2. Accessing the Fuel Pump Module:

   • For models with a dedicated fuel pump access cover: Remove the cover screws/lock ring retaining screws. Pry off the cover carefully using a flat head screwdriver if needed (don't damage the seal surface).
   • For models without a dedicated access cover: This involves removing the rear cargo box/bed. Steps typically include: Removing the seat or cargo box sides/bulkhead panels if present, unbolting the cargo box at attachment points (usually bolts accessible from underneath or inside the box itself), disconnecting any electrical connectors (tail lights, brake light switch), and carefully lifting out the entire cargo box assembly. The pump module is mounted on top of the fuel tank beneath where the cargo box sat. Refer to your manual.

3. Disconnecting the Fuel Pump Module:

   • Once the module is visible, carefully disconnect the main electrical connector. Press any locking tab and pull straight apart. Avoid pulling on wires.
   • Identify the fuel supply (larger diameter) and fuel return (smaller diameter) lines. Note their positions carefully!
   • Use the correct fuel line disconnect tool(s). Slide the tool between the line connector and the module nipple, pushing it in fully to release the locking tabs. Pull the fuel line connector off the nipple. Repeat for the second line. Be prepared for residual fuel spillage – have towels and a drain pan ready. Depressurizing earlier minimizes this. Some newer models have a single supply line with return-less systems. There may also be a smaller vapor line – disconnect similarly if present. CAUTION: Replace any damaged or worn o-rings inside the quick-connect fittings immediately. They are a common source of fuel leaks after reassembly.

4. Removing the Old Module Assembly:

   • Locate the large metal or plastic locking ring securing the module assembly to the fuel tank. This ring usually has tabs or lugs.
   • Using a brass drift punch and hammer, or a specialized spanner wrench designed for fuel pump lock rings, strike the ring firmly in a Counter-Clockwise (Left-Loosey) direction. Stubborn rings may require significant force – use care not to damage the ring or tank.
   • Once unthreaded, lift the entire fuel pump module assembly straight out of the fuel tank. Be careful not to bend the fuel level sending unit float arm.
   • Place it on a clean surface or shop towel.

5. Transferring Components (If Replacing Pump Element Only):

   • If replacing only the pump motor: Carefully disassemble the old module. This usually involves unclipping the pump motor from the bracket, detaching wires (note polarity!), transferring the strainer sock, and reinstalling the float arm assembly onto the new pump. Transferring the delicate level sender requires precision. This is significantly more error-prone than using a complete assembly. Opting for the complete assembly bypasses this complex step.

6. Preparing & Installing the New Module:

   • If using a complete new assembly, inspect it carefully. Ensure it looks identical to the old one.
   • VERY IMPORTANT: Clean the sealing surface on the top of the fuel tank thoroughly. Any debris will cause leaks. Wipe clean with a lint-free cloth. Ensure the new module gasket or large O-ring (depending on design) is seated correctly in its groove on the module housing. A small bit of clean petroleum jelly can slightly help it stay in place during installation. DO NOT use regular grease.
   • Carefully lower the NEW pump module assembly straight down into the fuel tank. Ensure the float arm doesn't get bent. Align the module housing correctly with the lock ring tabs on the tank.
   • Hand-thread the NEW locking ring onto the tank opening, aligning any tabs/lugs. Finger tighten securely initially.
   • Use the brass punch and hammer or spanner wrench to firmly tap the ring Clockwise (Right-Tighty) to secure it. Strike evenly around the ring. Tighten until the ring contacts the tank flange fully. DO NOT OVERTIGHTEN, as this can crack the plastic fuel pump housing or damage the tank. Secure is sufficient.

7. Reconnecting Fuel Lines & Electrical:

   • Push the fuel line connectors onto their respective nipples until you hear or feel a distinct CLICK. Give each line a firm tug to confirm they are locked. Failure to lock causes fuel leaks or suction of air.
   • Reconnect the main electrical connector securely, ensuring any locking tab engages.

8. Final Assembly & Testing:

   • Reinstall the fuel pump access cover with its gasket (if applicable). Torque screws to spec (usually not very tight). If you removed the entire cargo box/bed, carefully reinstall it, reconnect any electrical connectors, and secure all bolts/pieces per your manual.
   • Reinstall the fuel pump fuse.
   • Reconnect the NEGATIVE (-) battery terminal.
   • Turn the ignition key to the "ON" position without starting the engine. Listen closely for the distinct 2-5 second priming sound from the new pump. This confirms power and operation. Cycle the key ON-OFF 2-3 times to fully pressurize the system.
   • Carefully inspect all connections near the pump module, under the ATV, and around the engine for any sign of fuel leaks. This is critical. Run your hands (wear gloves) along connections feeling for wetness. Sniff for fumes. Fix any leaks immediately.
   • If no leaks are present, start the engine. It may crank briefly before starting as air is purged from the fuel lines. Observe the engine idle quality and response to throttle inputs. Take a short, cautious test ride in a safe area, gradually increasing engine load to confirm normal operation and full power restoration.
   • Reset your odometer or maintenance reminder to track the new pump's lifespan.

(Expert Maintenance Tips for Maximizing Fuel Pump Longevity)

Prevention is far cheaper than replacement. Implement these crucial maintenance habits:

• Use Fresh, High-Quality Fuel: Purchase gasoline from reputable stations with high turnover. Avoid leaving fuel sitting in the tank unused for more than 30-60 days. If storing, add a fuel stabilizer (STA-BIL, Sea Foam, etc.) before filling the tank to the top to minimize air space (which prevents condensation). Run the engine for 5-10 minutes after adding stabilizer to circulate it.
• Keep the Tank Adequately Full: Make it a habit to refill the tank when it drops to around 1/4 full. This ensures the pump motor remains submerged and cooled adequately during operation. Never continuously run the tank nearly empty.
• Replace the Fuel Filter Regularly: The inline fuel filter is your pump's first line of defense against contaminants. A clogged filter forces the pump to work excessively hard, increasing wear and heat. Consult your owner's manual for the replacement interval (often annually or every few hundred hours/miles). Stick to this strictly. Use a quality OEM or reputable aftermarket filter. Relocating the filter outside the tank during replacement is sometimes feasible and makes future changes easier.
• Minimize Tank Sediment: Occasionally drain a small amount of fuel from the tank drain plug into a clear container to check for water or sediment. If present, drain more thoroughly and consider tank cleaning if severe.
• Address Electrical Issues Promptly: Fix corroded battery terminals, loose grounds, or damaged wiring immediately. Consistent electrical voltage is crucial for pump motor health.

(Addressing Common Questions)

• Q: How much does a Polaris Sportsman 570 fuel pump replacement cost?
  • A: DIY using a quality aftermarket complete assembly: $100-$220 for the part + cost of filters/o-rings/gaskets. DIY using OEM complete assembly: $250-$400+. Professional Dealer/Labor Cost: Typically $450-$800+, including parts, labor (usually 1.5-2.5 hours), and shop fees.
• Q: Can I clean a dirty Sportsman 570 fuel pump to fix it?
  • A: Generally, no. While sediment around the pump strainer can sometimes cause symptoms (and cleaning it might temporarily help in rare cases of extreme clogging), the pump itself has tiny internal parts and seals. Once internal wear or electrical motor issues occur, cleaning is ineffective. Contamination often causes permanent damage. Replacement is the reliable solution.
• Q: How long should a new Polaris Sportsman 570 fuel pump last?
  • A: With proper care (using good fuel, keeping the tank above 1/4, changing the filter regularly), a quality OEM or reputable aftermarket pump should provide 5+ years or thousands of hours of reliable service. Lifespan significantly decreases with neglect (low fuel levels, contaminated gas).
• Q: What happens if I drive with a weak fuel pump?
  • A: Continued operation stresses the pump further, accelerating its demise. More critically, insufficient fuel pressure causes lean running conditions (too much air, not enough fuel). Lean mixtures make the engine run excessively hot, potentially causing catastrophic damage to pistons, rings, valves, and the catalytic converter due to pre-ignition or detonation. Never ignore symptoms.
• Q: Is replacing the pump module difficult?
  • A: Moderate difficulty for a DIYer with standard mechanical aptitude and the right tools. Models with an access cover under the seat/bed are significantly easier (Difficulty: 6/10). Models requiring cargo box removal add complexity and time (Difficulty: 7/10). The physical act of changing the module itself is straightforward once accessed. The challenges are access, proper electrical/fuel line handling, ensuring no leaks, and working safely around fuel. Having a service manual is essential.

(Final Points)

A failing Polaris Sportsman 570 fuel pump is a common, frustrating, but manageable issue. By recognizing the symptoms early (hard starting, sputtering under load), performing key diagnostic checks (listen for priming, test pressure), and choosing a quality replacement (complete module recommended), you can restore reliable performance. Prioritizing proactive maintenance – particularly using clean fuel, keeping the tank above 1/4 full, and religiously replacing the inline fuel filter – is the single best way to extend the life of your new pump and prevent unexpected breakdowns on the trail. If DIY isn't feasible, consult a trusted Polaris-certified mechanic to ensure the job is done safely and correctly. Addressing fuel delivery issues promptly protects both your ride and your wallet.