2015 Polaris Ranger 570 Fuel Pump: Diagnosis, Replacement, and Crucial Insights

The 2015 Polaris Ranger 570 fuel pump is a critical component, and its failure often manifests through hard starting, power loss, stalling, or failure to run. Diagnosing electrical faults, pressure drops, or contaminant damage typically points to a failing pump. Replacement requires accessing the fuel tank, installing a new pump assembly (or complete module), and verifying correct operation. While challenging, DIY replacement is feasible with proper guidance; preventative care focuses on fuel quality and filter maintenance.

Understanding the Critical Role:
The fuel pump in your 2015 Polaris Ranger 570 is the heart of its fuel delivery system. Its sole purpose is to draw gasoline from the fuel tank and deliver it under high pressure to the electronic fuel injection system. The Engine Control Unit requires a precise volume and pressure of fuel to correctly mix with air and create combustion. Without the fuel pump functioning correctly, the engine either won't start, won't run well, or won't run at all. The fuel pump assembly in the Ranger 570 includes not only the pump motor itself but also often a pre-filter (sock), a main filter, a pressure regulator, and electrical connections, housed inside the fuel tank. Its location protects it from debris but subjects it to constant immersion in fuel and potential internal contaminants.

Recognizing the Symptoms of Failure:
Spotting fuel pump trouble early is key to preventing a total breakdown. Common signs specific to the 2015 Ranger 570 include:

• Engine Cranking Without Starting: The engine turns over strongly but refuses to fire up. This is often the most common first sign.
• Intermittent Power Loss or Hesitation: The engine loses power unexpectedly during operation, especially under load or uphill, sometimes accompanied by sputtering. It may recover briefly.
• Engine Stalling: The engine cuts out unexpectedly while idling or driving, often restarting later or requiring a long cooldown period.
• Long Crank Times: The engine takes significantly longer than usual to start, indicating reduced fuel pressure build-up.
• Loss of Power at Higher Speeds or RPM: The Ranger fails to reach its usual top speed or struggles when accelerating.
• Engine Surging: Engine RPM fluctuates unpredictably while trying to maintain a steady throttle input.
• Whining or Humming Noise from Under the Seat (Fuel Tank Area): A loud or unusually high-pitched noise compared to the normal pump whir is a strong indicator of bearing wear or pump stress.

Core Causes of Fuel Pump Problems:
Several factors can lead to a failed fuel pump in your Ranger 570:

• Normal Wear and Tear: The pump motor contains bearings and brushes that physically wear out over time and operational cycles.
• Electrical Failures: Corroded or damaged electrical connections (plug/connector, wires) can prevent the pump from receiving the voltage it needs. Blown fuses related to the fuel system also cut power. The pump relay failing is another possibility.
• Contamination: Dirt, rust, sediment, or water entering the fuel tank acts like sandpaper inside the pump, accelerating wear on its internal surfaces and vanes. This is often the primary cause for premature failures.
• Clogged Filters: A severely clogged pre-filter sock inside the tank or the main inline fuel filter forces the pump to work much harder, generating excess heat and strain that leads to early burnout.
• Running Low on Fuel: Operating the Ranger frequently with a near-empty tank can cause the pump to overheat. Fuel acts as a coolant for the pump motor; low levels lead to reduced cooling and potential burnout. It also increases the chance of sucking up concentrated contaminants settled at the tank bottom.
• Fuel Pressure Regulator Issues: While part of the pump assembly, a failing regulator can cause symptoms mirroring pump failure by not maintaining correct pressure (typically around 40-45 PSI for EFI Rangers).

Step-by-Step Diagnosis:
Before condemning the pump, perform these checks:

1. Listen for Prime: Turn the ignition key to the "ON" position (do not start). You should clearly hear the pump whir (prime) for approximately 2-3 seconds. No sound strongly suggests an electrical issue or a completely failed pump.
2. Check Related Fuses: Locate the fuse box. Consult your owner's manual for the exact location of the fuel pump fuse. Visually inspect the fuse to see if the element is broken or use a multimeter to check for continuity. Replace if blown.
3. Inspect Electrical Connection: Access the electrical connector on top of the fuel tank (usually near the fuel line outlet). Check for corrosion, bent pins, looseness, or damaged wires. Clean if necessary with electrical contact cleaner. Try wiggling the connection while someone turns the key to ON to check for intermittency.
4. Test Fuel Pressure: *The Most Definitive Test.*
   • Rent or purchase a fuel pressure test kit compatible with Polaris EFI systems.
   • Locate the test port on the fuel rail near the throttle body/injectors (a small Schrader valve, similar to a tire valve stem). CAUTION: Relieve pressure by carefully depressing the valve with a rag first.
   • Attach the pressure gauge securely to the test port.
   • Turn the ignition key to ON. Note the pressure reading during the prime cycle and if it holds steady (should be within spec: approx. 40-45 PSI is typical, verify service manual for exact spec).
   • Start the engine and check pressure at idle. It should remain relatively constant.
   • Pinch the return fuel line briefly (use appropriate pliers designed not to damage the line) – pressure should jump significantly, indicating the pump is capable of higher output.
   • Low or zero pressure, or pressure that bleeds off rapidly after priming, points strongly to a failing pump (or a severe restriction/leak).
5. Inspect Fuel Filter Condition: If accessible, check the main inline fuel filter. While replacing a clogged filter might help, if the pump was strained for a long period, damage may already be done.
6. Consider Fuel Quality: Was old or contaminated fuel recently used?

2015 Ranger 570 Fuel Pump Replacement Options:
Once diagnosed, you have choices:

1. Complete Fuel Pump Module Assembly: This is the most common and recommended replacement. It includes the pump motor, integrated strainer (sock), regulator, and usually a mounting bracket and lock ring, all pre-assembled in a new housing. Pros: Simple plug-and-play installation. Cons: Higher cost ($150-$300 typical).
2. Pump Motor Only: You purchase just the core pump motor and swap it into your existing pump assembly housing. This requires disassembling the old housing, handling old seals, and requires significant care. Pros: Lower cost ($50-$150 typical). Cons: More time-consuming, risk of improper reassembly, potential damage to old housings or seals, old filters and regulator remain. Only recommended if you are mechanically confident and have verified the housing and regulator are sound.
3. OEM vs. Aftermarket:
   • OEM: Polaris/Airtex. Generally highest quality assurance, exact fitment. Higher price.
   • Reputable Aftermarket Brands: Sykik (often considered the best aftermarket for Powersports), Carter Pumps, Fuel Pumps UMP, Quantum Fuel Systems. Offer solid performance and reliability at a lower price point. Thoroughly research reviews before choosing a generic/low-cost aftermarket brand.

Step-by-Step Replacement Guide (Complete Module):
WARNING: Gasoline is extremely flammable. Work in a well-ventilated area away from sparks or ignition sources. Relieve fuel system pressure before disconnecting lines. Have a fire extinguisher nearby.

1. Gather Tools: Replacement pump module, ratchet/socket set (metric), screwdrivers (Phillips & flathead), pliers (needle nose, channel locks), fuel line disconnect tools (size specific to Polaris 5/16" & 3/8" quick-connects are common), shop towels, drain pan, safety glasses, nitrile gloves.
2. Locate Fuel Tank: Under the driver's seat/center of the cab floor area on the Ranger 570.
3. Depressurize System: Carefully depress the Schrader valve on the fuel rail with a rag to release any residual pressure.
4. Disconnect Battery: Negative cable first for safety.
5. Access Fuel Pump: Remove the seat base cover plate. This usually involves removing several screws around the perimeter.
6. Disconnect Electrical Connector: Carefully unplug the multi-pin electrical connector on top of the pump module.
7. Disconnect Fuel Lines: Identify the fuel supply (higher pressure, to engine) and fuel return (lower pressure, back to tank) lines. Use the appropriate fuel line disconnect tool to safely release the quick-connect fittings on both lines. Some may have locking clips that need to be pried up first. Place rags under lines to catch fuel drips.
8. Remove Lock Ring: Using a large flat blade screwdriver and hammer, carefully tap counter-clockwise (lefty-loosey) on the lock ring tabs to unscrew it. Caution: Metal shavings! Wear eye protection. The ring may be stiff. Channel locks can sometimes be used gently on the tabs if needed.
9. Lift Out Old Module: Carefully lift the entire fuel pump module assembly straight up and out of the tank. Be mindful of the fuel level sender float arm – don't bend it. Drain any residual fuel into a drain pan.
10. Transfer Sending Unit (If Necessary): If your new module doesn't include a fuel level sending unit OR it's different, carefully remove the old sending unit from the assembly and transfer it to the new module. Note the orientation! Not always required, depends on the replacement part.
11. Compare Old and New: Verify the new module matches the old one in size, port locations, and connector pin layout. Crucial step! Install new seals/gaskets if provided.
12. Install New Module: Align the new pump module correctly (reference tabs/notches) and lower it straight down into the tank. Ensure the float arm moves freely.
13. Secure Lock Ring: Screw the large lock ring clockwise by hand as far as possible. Tighten it securely using the screwdriver/hammer or channel locks method. Avoid over-torquing.
14. Reconnect Fuel Lines: Pressurize the quick-connect fittings until you hear a distinct "click" and feel them lock securely onto the module nipples. Give each line a firm tug to verify connection.
15. Reconnect Electrical Connector: Plug the connector back in firmly, ensuring it clicks/locks.
16. Reinstall Cover Plate: Place the seat base plate back and secure all screws.
17. Reconnect Battery: Negative cable last.
18. Initial Test: Turn the ignition key to ON. Listen for the fuel pump to prime for 2-3 seconds. Check for any fuel leaks around the pump module area and at the Schrader valve on the fuel rail.
19. Start Engine: Start the Ranger. It might crank slightly longer initially as fuel pressure builds. Allow it to idle, checking for smooth operation and listening for abnormal pump sounds. Recheck for leaks.
20. Confirm Operation: Take a short test drive to ensure normal power delivery and no hesitation/stalling.

Troubleshooting After Replacement:

• No Prime/No Start: Verify ignition power at the pump connector using a multimeter during prime cycle. Recheck main fuses, relays, and all connections. Ensure pump lock ring is fully sealed.
• Engine Cranks But Won't Start: Re-check fuel pressure at the rail. Possible issue with pressure regulator in new module (rare), incorrect installation preventing flow, or severe airlock (try cycling key ON/OFF 3-4 times before cranking).
• Poor Performance/Rough Idle: Recheck fuel lines are connected correctly (Supply and Return swapped?). Verify no kinks in fuel lines. Consider residual air in lines clearing out after a few minutes of operation. If persistent, recheck fuel pressure.
• Leaks: Tighten lock ring more securely, ensure seals/gaskets are correctly installed and undamaged, verify fuel line quick-connects are fully seated.

Preventative Maintenance for Longevity:

• Use Quality Fuel: Purchase fuel from reputable stations. Consider Top Tier fuel if available.
• Avoid Ethanol Issues: Use ethanol-free gasoline (E0) whenever possible. Ethanol attracts moisture, corrodes components, degrades rubber seals faster, and provides less energy. If E10 is unavoidable, use fuel stabilizer year-round, especially if the Ranger sits unused.
• Replace Fuel Filters: Strictly follow the maintenance schedule in your owner's manual for replacing both the inline fuel filter (if external) and the in-tank filter sock. More frequent changes are beneficial in dusty/dirty environments. This is the single best action to protect the pump.
• Keep the Tank Adequately Full: Avoid consistently running the tank very low. Refuel when the gauge hits 1/4 tank.
• Prevent Water Contamination: Ensure the fuel cap seals properly. Avoid fueling in severe dust storms or heavy rain if possible. Ensure tank vents are clear.
• Winter Storage: Add fuel stabilizer to a nearly full tank before storing for extended periods. Run the engine for 5 minutes after adding stabilizer to circulate it through the system and pump.

Compatibility Clarifications:

• Polaris Ranger 500: Often uses the same fuel pump assembly as the Ranger 570. CONFIRMATION IS ESSENTIAL. Compare part numbers before purchase.
• Polaris Ranger 800/900/1000: Typically use different, higher-flow pumps. A Ranger 570 pump will not work in these larger engines.

Conclusion:
While replacing the fuel pump on your 2015 Polaris Ranger 570 requires careful disassembly around the fuel tank, proper diagnosis, and meticulous installation, it is a manageable repair with the right preparation and attention to detail. Recognizing the key symptoms early, accurately testing fuel pressure before replacement, and choosing a quality replacement module (preferably a complete assembly from Sykik, OEM, or other reputable brands) ensure a successful outcome. Remember that ongoing preventative care – primarily using clean fuel, replacing filters on schedule, and avoiding consistently low fuel levels – is the most effective way to maximize the lifespan and reliability of your Ranger 570's fuel system and keep you confidently exploring for years to come.