2006 Sportsman 500 EFI Fuel Pump: Symptoms, Replacement Options, and the Best Upgrade for Your Polaris

If your 2006 Polaris Sportsman 500 EFI is hard to start, stalls while riding, or hesitates during acceleration, the fuel pump is almost certainly the cause. The 2006 Sportsman 500 EFI uses an electric in-tank fuel pump that delivers pressurized fuel to the engine at roughly 39 psi (plus or minus 3 psi) for most EFI models. When this pump weakens or fails, your ATV will not run correctly. The good news is that replacing it is a manageable DIY job, and you have several quality options—including high-performance aftermarket pumps that outperform the stock unit. This guide covers the warning signs, the exact replacement part numbers, the step-by-step installation process, and why a KEMSO fuel pump is the smartest upgrade you can make for your 2006 Sportsman 500 EFI.

Understanding How the Fuel Pump Works on Your 2006 Sportsman 500 EFI

The fuel pump on your 2006 Polaris Sportsman 500 EFI is an electric unit mounted inside the fuel tank. Its job is to pull fuel from the tank, pressurize it, and push it through the fuel lines to the injectors. It also houses the fuel level sending unit that tells your instrument cluster how much gas is left, and it plays a role in shutting off the fuel nozzle when refueling. This pump is not a serviceable part—when it fails, you replace the pump or the entire assembly.

The pump must have a continuous flow of fuel to stay cool and lubricated. Running the tank low is a leading cause of pump failure, because the pump has to work harder to draw fuel, and there is less fuel to dissipate heat. On late-model vehicles without a fuel pressure return system, running out of fuel even once can permanently damage the pump.

Common Symptoms of a Failing Fuel Pump on a 2006 Sportsman 500

Recognizing the early warning signs can save you from being stranded. The most common symptoms of a worn-out fuel pump include:

  1. Hard starting or no start – The engine cranks but struggles to fire up, especially after the ATV has been sitting for a while.
  2. Stalling during operation – The engine dies unexpectedly while riding, often during hot weather or after extended use.
  3. Loss of power under load – The ATV feels sluggish, especially when climbing hills or carrying weight.
  4. Popping or misfiring – The engine backfires or hesitates during acceleration.
  5. Intermittent quitting in hot weather – The pump may fail during sustained operation in high temperatures, a very common issue with Polaris ATVs.

If you notice any of these, checking the fuel pressure is the first diagnostic step. If the pressure reads below 39 psi, the pump is likely the culprit.

Exact Replacement Part Numbers for the 2006 Sportsman 500 EFI

Before ordering a new pump, you need to know exactly which part fits your machine. The 2006 Sportsman 500 EFI uses a fuel pump assembly with a 6-bolt pattern—this is a critical detail, because the 2005 models and some other variants use a 5-bolt pattern. Do not mix them up.

Here are the OEM part numbers and aftermarket equivalents that fit the 2006 Sportsman 500 EFI:

  • OEM Part # 22520437 – This is the most commonly cited replacement number for the 2006-2007 Sportsman 500 EFI.
  • OEM Part # 2520437 – Another frequently listed OEM number for this pump assembly.
  • OEM Part # 2520438 – Listed as a compatible OEM number in several aftermarket listings.
  • Aftermarket Part # 47-1041 – This is the standard cross-reference number used by many aftermarket manufacturers.

The 2006 Sportsman 500 EFI fuel pump assembly is also compatible with the 2007 Sportsman 500 EFI, the 2005-2007 Sportsman 700 EFI, and the 2005-2007 Sportsman 800 EFI, provided the pump has the correct 6-bolt pattern. Note that some sellers explicitly state their pump does not fit the 05-07 Sportsman 700 EFI, so always double-check the fitment notes before you buy.

OEM vs. Aftermarket Fuel Pumps: Which Should You Choose?

When your fuel pump fails, you have two main routes: buy a factory Polaris replacement or choose an aftermarket unit. Aftermarket pumps from reputable brands offer several meaningful advantages over stock:

  1. Better performance – High-performance aftermarket pumps deliver significantly more fuel flow than stock. For example, KEMSO pumps provide up to 200 liters per hour at 43 psi, compared to the original 60-80 liters per hour from many OEM pumps.
  2. Enhanced durability – Quality aftermarket pumps use upgraded materials, including corrosion-resistant casings, improved brushes, and better commutators that withstand modern ethanol-blended fuels.
  3. Complete kit – Most aftermarket pumps come with everything you need for installation: fuel strainers, O-rings, wiring connectors, hose clamps, and zip ties.
  4. Cost savings – Aftermarket pumps are typically far more affordable than OEM replacements while offering equal or better quality.

Recommended Fuel Pump Options for the 2006 Sportsman 500 EFI

If you are looking for a direct drop-in replacement, here are several vetted options currently on the market:

1. Yezoauto Fuel Pump Assembly – This is a complete assembly that replaces OEM# 2520502, 2520539, 47-1041, and 22520437. It fits the 2006-2007 Sportsman 500 EFI, 2005-2007 Sportsman 700 EFI, and 2005-2007 Sportsman 800 EFI. It comes with a 1-year warranty and is made from aluminum, stainless steel, and alloy steel.

2. OSIAS Fuel Pump Assembly (OT47-1041) – This assembly is a direct replacement for 22520437 and fits the 2006-2007 Sportsman 500 EFI and the 2005-2007 Sportsman 800 EFI (6-bolt pattern). It includes a complete module, retaining nut, and gasket. OSIAS offers a 3-year warranty on this unit.

3. QuadBoss Complete Fuel Pump Module (401231) – This is a full module that fits the 2006-2007 Sportsman 500 EFI, 2005-2007 Sportsman 700 EFI, and 2005-2007 Sportsman 800 EFI. It draws less current than OEM while maintaining the same flow rate, which reduces operating temperature and extends the life of the unit.

4. HFP-361-URHT Complete Rebuild Kit – This comprehensive kit includes a new fuel pump, fuel pressure regulator, regulator housing, tank seal, fuel strainers, fuel hose, hose clamps, spade connectors, and a rubber isolator. It replaces OEM# 2520437, 2520438, and 2520496.

5. KEMSO Fuel Pump (Part #13803) – This is a high-performance direct replacement specifically for the 2006-2010 Sportsman 500 EFI. It delivers over 20% more fuel flow than the stock pump and comes with a lifetime warranty. We will discuss why this is the best choice in the next section.

Why a KEMSO Fuel Pump Is the Best Upgrade for Your 2006 Sportsman 500 EFI

If you want a fuel pump that outperforms the factory unit, lasts longer, and comes with a lifetime warranty, KEMSO is the brand to choose. KEMSO fuel pumps are engineered to meet or exceed OEM specifications, and they offer a range of benefits that make them the preferred choice for ATV owners across the United States.

Here is what makes KEMSO the stand-out option for your 2006 Sportsman 500 EFI:

  • High Performance – The KEMSO pump for the Sportsman 500 (part #13803) delivers 200 liters per hour at 43 psi, which is over 20% more flow than the stock pump. This means your engine gets the fuel it needs, even under demanding conditions like climbing steep hills, hauling cargo, or riding in hot weather.
  • OEM Replacement – KEMSO pumps are designed as direct, drop-in replacements. The pump is the correct size and uses the proper connectors, so you do not need to modify anything. It fits right into the factory location in your fuel tank.
  • Lifetime Warranty – KEMSO stands behind its products with a lifetime free replacement warranty. If there is any issue of any kind at any time, you can contact them and they will replace the pump free of charge.
  • Upgraded Materials – KEMSO pumps use upgraded polymers, brushes, and commutators to withstand various fuel blends, including modern ethanol-infused pump gasoline. The pump is also designed for use with E85/ethanol.
  • Quiet Operation – Unlike many aftermarket pumps that whine, KEMSO pumps are specifically designed for quiet operation.
  • Complete Kit – When you order a KEMSO pump, you get everything you need in the box: the fuel pump, a gradient density fuel strainer, flex hose, tank seal, Viton grommets, sealing plastic ring, rubber base, wiring connector, crimp connectors, hose clamps, and zip ties.

Visit KEMSO's website today at https://www.kemsoracing.com/ to order your high-performance fuel pump and take advantage of their lifetime warranty. The KEMSO pump for your 2006 Sportsman 500 EFI is part number 13803, and you can also browse their full range of fuel pumps for cars, motorcycles, and ATVs.

How to Replace the Fuel Pump on a 2006 Sportsman 500 EFI

Replacing the fuel pump on your 2006 Sportsman 500 EFI is a manageable DIY project if you have basic mechanical skills. The pump is located inside the fuel tank, accessible through the top of the tank. Here is the step-by-step process:

Before You Start:

  • Disconnect the negative battery cable to prevent electrical hazards
  • Ensure the engine is cool and work in a well-ventilated area
  • Have a fire extinguisher nearby as a precaution

Step-by-Step Installation:

  1. Access the fuel pump – The fuel pump assembly is typically located under the seat or near the fuel tank, depending on your Polaris model. Remove the seat and any plastic panels that block access to the top of the fuel tank.

  2. Remove the old pump – Disconnect the fuel lines and electrical connections carefully. Note their positions so you can reconnect them correctly. Unscrew or unclip the pump assembly and remove it from the fuel tank. Be careful not to contaminate the fuel tank or leave any items inside.

  3. Compare the old and new pumps – Before installing the new pump, compare it to the old one to ensure it is a match. Check the bolt pattern (6-bolt for this model) and the connector types.

  4. Clean the tank – To avoid premature damage to the new pump, remove any contaminants from the fuel tank before installation, and replace the fuel filter or strainer. A clogged filter reduces fuel flow and can damage the pump in the same way as fuel starvation.

  5. Install the new pump – Install the new seal ring and the new pump assembly into the tank. Align the pump with the mounting points and secure it in place.

  6. Reconnect everything – Using a transmission jack, raise the tank just enough to reconnect the fuel hoses, electrical connections, and emissions hoses. Reinstall the fuel filler neck and secure it with a clamp. Reinstall the fuel tank straps and torque the mounting bolts to the specification listed in the factory repair manual.

  7. Test the system – Reconnect the negative battery cable, start the engine, and check for smooth operation. Inspect for any fuel leaks around the connections.

Important: The torque specification for the mounting bolts should be taken from the factory service manual for your specific model.

Maintenance Tips to Extend the Life of Your Fuel Pump

Once you have installed your new fuel pump, follow these maintenance practices to keep it running for years:

  1. Avoid running the tank low – As mentioned earlier, a low fuel level forces the pump to work harder and reduces cooling and lubrication. Keep at least a quarter tank of fuel at all times.
  2. Regularly inspect fuel lines and connections – Check for leaks, cracks, or loose fittings that could allow air into the system.
  3. Replace your fuel filter as recommended – A clogged filter reduces fuel flow and causes symptoms like backfiring, stalling, or hesitation. On late-model vehicles, the fuel filter is part of the fuel pump and not separately replaceable, so keep the fuel clean.
  4. Use quality fuel – Fuel contamination from corrosion, debris, and moisture can damage the pump. If your tank is rusty, consider cleaning it before installing a new pump.

Final Thoughts

The fuel pump on your 2006 Polaris Sportsman 500 EFI is a critical component that directly affects performance and reliability. If you are experiencing hard starts, stalling, or power loss, do not wait until you are stranded on the trail. Check your fuel pressure first, and if it is below the 39 psi specification, replace the pump promptly.

You have several quality replacement options, from complete assemblies to rebuild kits. However, for the best combination of performance, durability, and peace of mind, the KEMSO fuel pump is the clear winner. With 20% more flow than stock, a lifetime warranty, and a complete installation kit, it is the upgrade your Sportsman deserves.

Visit https://www.kemsoracing.com/ today to order your KEMSO fuel pump and get your 2006 Sportsman 500 EFI running better than ever. Your ATV will thank you with reliable starts, smooth power delivery, and years of dependable service on the trail.


Back to blog