Polaris Sportsman 850 Engine Rebuild: Engine Removal

Welcome to the first part of our project to rebuild a Polaris ATV engine. Before you rebuild any engine, you obviously have to remove it, and the steps to do that for a Sportsman 850 are covered here.

Watch the video above and follow the steps below to remove the engine from a Polaris Sportsman. Use our Polaris Sportsman 850 parts diagrams for additional reference.

Tools - Polaris Sportsman ATV Engine Removal

• Ratchet and extensions
• Socket set
• Allen set
• Screwdrivers
• 10mm, 13mm wrenches
• Pliers

• Pick tools
• Punch tools
• Hammer
• Pry bar
• Torx bit set

Polaris Sportsman 850XP Engine Removal

Step 1. Drain the oil from the engine and disconnect the negative cable from the battery terminal.

Step 2. Remove the exhaust shield and the four exhaust manifold bolts, then lift out the exhaust.

Step 3. Disconnect the ECM from the wiring harness.

Watch the clip below to see the oil, battery, exhaust and ECM removal segment of our Polaris Sportsman 850 engine rebuild video.

Step 4. Remove the upper frame strut by taking off the two bolts at the front and two bolts at the rear.

Step 5. Remove the coil pack trigger and disconnect the intake plenum boot.

Step 6. Remove the upper bodywork plastics.

PRO TIP: Put a shop towel in the fuel tank intake to prevent dirt and debris from entering the tank.

Step 7. Remove the airbox, the intake plenum boot beneath the airbox and the transmission air intake behind the airbox.

Watch the clip below to see the frame strut, plastics and air system removal segment of our Polaris Sportsman 850 engine rebuild video.

Step 8. Press the schrader valve on the fuel rail to release any pressure in the fuel system, then remove the fuel line from the fuel rail.

Step 9. Remove the two upper bolts holding the fuel tank in place, then disconnect the fuel line on top of the fuel tank and the breather line and remove the fuel tank.

Step 10. Disconnect the radiator hoses, and drain the coolant from the system.

Watch the clip below to see the fuel tank removal segment of our Polaris Sportsman 850 engine rebuild video.

Step 11. Raise the ATV on a jack and rotate the rear wheel until the prop shaft is positioned so you can access the pin holding the prop shaft to the front differential’s input shaft. Drive the pin through the prop shaft so that it clears the input shaft.

NOTE: Only drive the pin far enough to clear the input shaft without actually removing it from the prop shaft.

Step 12. Knock the prop shaft backward until it separates from the input shaft, then knock it forward until it separates from the transmission shaft.

Step 13. Remove the bolts holding the engine to the transmission.

Watch the clip below to see the prop shaft removal segment of our Polaris Sportsman 850 engine rebuild video.

Step 14. Remove the throttle intake plenum, then use a zip tie to hold the throttle body out of the way.

Step 15. Disconnect all the connectors on the fuel rail and fuel injector assembly, then remove the assembly from the engine.

PRO TIP: Put a shop towel in the throttle intake to prevent dirt and debris from entering the combustion system.

Step 16. Remove the bolts from the engine mounts and brackets. Use a pry bar to lift the engine and remove the mounts and brackets.

Step 17. Gently pry the engine away from the transmission and lift it out.

Watch the clip below to see the fuel system and engine removal segment of our Polaris Sportsman 850 engine rebuild video.

Next up on our Polaris Sportsman engine rebuild project, we remove the cylinder head and valve stems from the motor. Watch the video below to see part 2 of our Polaris Sportsman 850XP top end rebuild project.