Description

Polaris Sportsman 400 Engine Rebuild Service (2001–2013)

The Polaris Sportsman 400 has built its name on reliability. However, after years of use, even the toughest engines start to lose power, develop wear, and become less consistent. Instead of replacing the machine, a full rebuild brings it back to the way it should run.

At REV6, we tear down every engine, inspect each component, and address common wear areas right away. Then we rebuild it using proper tolerances and refreshed internals. As a result, your Sportsman starts easier, runs smoother, and holds steady power when you need it most.

What Gets Rebuilt

This rebuild focuses on restoring sealing, correcting clearances, and improving long-term durability.

• Complete teardown and inspection of all internal components
• Cylinder head cleaned, decked, rebuilt, and set to specification
• Valve guides inspected and replaced when needed
• Valves and seats recut and vacuum tested for proper sealing
• Camshaft components cleaned, polished, and inspected
• Refurbished crankshaft
• Cylinder inspected, bored and honed, or replaced as needed
• New moly-coated piston and rings installed
• Timing chain inspected and replaced when needed
• Refurbished oil pump assembly
• Engine cases inspected for cracks, wear, and integrity
• All gaskets and seals replaced
• Final assembly torqued to factory specifications

Note: Final build details may vary depending on the condition of your core.

Built for Long-Term Use

Once clearances are corrected and sealing is restored, the engine runs smoother and delivers consistent power. Because of that, your Sportsman stays dependable for work, hauling, and everyday riding.

Warranty Coverage

Every engine includes a 1-year warranty. In addition, you can upgrade to a 2-year no-fault plan for added protection.

Review full details on our warranty policy, visit the FAQ page, or contact our team if you need help before ordering.

Core Options

You can send in your engine core or choose a refundable $500 core deposit. Once your core passes inspection, the deposit is returned in full. If the core has damage beyond normal wear, deductions may apply.

If you need your engine first, ask about core exchange options and we’ll walk you through it.

Looking for Parts Instead?

If you’re not ready for a full rebuild, you can find top and bottom end kits, transmissions, cylinders, pistons, rings, crankshafts, gaskets, seals, valves, clutch components, and more in our
Polaris Sportsman 400 parts catalog.

Before First Startup

Proper break-in helps everything seat correctly and improves long-term reliability.

Follow the engine break-in procedure or visit the Help Center for additional guidance.

Turnaround Time

Most engines ship within 5–10 business days after we receive your core.

Take Action

If your Sportsman 400 is starting to lose power or show its age, rebuilding it now keeps your machine dependable and ready for the next job.

Get back on the trail with confidence.

We proudly support veterans and active servicemembers with available discounts—thank you for your service.