Hey guys! So, you're here because you're either a proud owner of a Polaris Sportsman 850 or you're thinking about joining the club. Awesome choice! The Sportsman 850 is a beast, a true workhorse, and a heck of a lot of fun to ride. But, like any machine that tackles tough terrains and pushes its limits, it needs a little TLC to keep it running smoothly. That's where this guide comes in. We're going to dive deep into everything you need to know about repairing and maintaining your Sportsman 850, from basic upkeep to more complex fixes. Buckle up, because we're about to get our hands dirty!

Understanding Your Polaris Sportsman 850

Before we jump into the nitty-gritty of repairs, let's take a moment to appreciate what makes the Polaris Sportsman 850 so special. This ATV is known for its powerful engine, its impressive suspension, and its ability to handle just about anything you throw at it. It's a favorite among hunters, farmers, and recreational riders alike. It's built tough, but it's not invincible. Knowing your machine is the first step in keeping it in top shape. It's like building a relationship; you gotta get to know your partner, right?

The Sportsman 850 typically boasts a liquid-cooled, four-stroke, twin-cylinder engine that delivers serious power. You've got electronic fuel injection (EFI) to keep things running efficiently. And the automatic PVT (Polaris Variable Transmission) transmission makes it super easy to ride, whether you're crawling over rocks or blasting through mud. The independent rear suspension (IRS) and on-demand all-wheel drive (AWD) system give you amazing control and handling. Trust me, these features are your best friends when the trail gets rough. Understanding these basics will help you diagnose problems and understand the repair process. So, take a moment to familiarize yourself with the key components of your ATV. This knowledge will pay dividends when it comes to maintenance and repairs. Knowing what's under the hood (or the plastic, in this case) is half the battle!

Regular Maintenance is Key

Okay, let's get real. The best way to avoid major repair headaches is through consistent, preventative maintenance. Think of it like brushing your teeth – do it regularly, and you'll avoid bigger problems down the road. For your Polaris Sportsman 850, this means sticking to a maintenance schedule. The owner's manual is your bible here. It outlines exactly what needs to be done, and when. Don't have the manual? No worries! You can usually find a digital copy online. Some of the most critical maintenance tasks include:

• Oil Changes: This is arguably the most important thing you can do. Fresh oil lubricates the engine, reduces friction, and keeps things running smoothly. Check your oil level regularly, and change it according to the manufacturer's recommendations (typically every 50-100 hours of use, or annually). Use the correct type of oil specified in your manual. Don't skimp on quality here; it's your engine's lifeline.
• Filter Changes: Air filters and oil filters keep dirt and debris out of your engine. Replace them regularly to prevent engine damage. Check your air filter frequently, especially if you ride in dusty conditions. Oil filters should be changed every time you change your oil.
• Spark Plugs: Spark plugs ignite the fuel-air mixture in your engine. Over time, they can wear out, leading to poor performance and fuel efficiency. Replace them according to the manufacturer's recommendations.
• Coolant: Your engine needs coolant to stay at the right temperature. Check your coolant level regularly, and flush and replace it according to the manufacturer's recommendations.
• Tire Pressure: Check your tire pressure before every ride. Properly inflated tires improve handling, ride comfort, and fuel efficiency.
• Greasing: Many components on your ATV, like suspension components, require regular greasing to keep them moving smoothly and prevent wear and tear. Consult your manual for greasing points and intervals.
• Belt Inspection: The drive belt is crucial for power transfer. Inspect it regularly for wear and tear, and replace it as needed. A failing belt can leave you stranded on the trail.

Following these simple steps will significantly extend the life of your Polaris Sportsman 850 and save you money in the long run.

Common Problems and How to Fix Them

Even with the best maintenance, things can go wrong. Let's look at some common issues and how to tackle them:

Engine Problems

• Hard Starting: If your Sportsman 850 is hard to start, it could be a number of things. Check the battery, spark plugs, fuel filter, and fuel pump. Make sure you're getting a good spark and that fuel is flowing properly. A weak battery is a common culprit, especially in cold weather. If the engine cranks but doesn't start, there might be an issue with the fuel system or ignition system. Check the fuel lines for clogs and the spark plugs for proper operation. If all checks out okay, then try to reset the computer system, there might be a fault code that needs to be reset.
• Loss of Power: If your ATV is losing power, check the air filter, fuel filter, and spark plugs. Make sure the engine is getting enough air and fuel. Check the exhaust system for restrictions, like a clogged spark arrester. Also, inspect the belt. A worn or damaged belt can cause a loss of power. A compression test will help to ensure the engine is performing as expected. Check for any leaks and replace damaged parts to restore power.
• Overheating: Overheating can cause serious engine damage. Check the coolant level, radiator, and cooling fan. Make sure the radiator is clean and free of debris. If the engine is overheating, stop riding immediately and let it cool down. Check for leaks in the cooling system. If the engine still runs hot, a potential bad thermostat can cause overheating. Replace to resolve the problem. Check the fan operation and replace it if required.

Electrical Problems

• Battery Issues: A dead battery is a common problem. Make sure the battery terminals are clean and tight. Check the battery voltage with a multimeter. If the battery won't hold a charge, it may need to be replaced. Check the charging system to make sure the battery is charging properly. If you are experiencing electrical issues, then check the fuses. Replace any blown fuses, and check the wiring for damage. Corrosion can also cause electrical problems. Clean any corroded connections with a wire brush and electrical contact cleaner.
• Lighting Problems: Check the bulbs and fuses. Make sure the wiring is connected properly. If the lights still don't work, there might be a problem with the switch or the stator. When the ATV is not charging or the lights are dim, it can be the stator or the rectifier/regulator. Use a multimeter to do a proper check before changing them.

Suspension and Steering Problems

• Rough Ride: Check the tire pressure and suspension settings. Inspect the shocks and springs for damage. A rough ride can be caused by worn shocks or improperly adjusted suspension. Make sure the shocks and springs are working properly. If the ride is still rough, consider upgrading your suspension. Also, check the ball joints and bushings for wear and tear.
• Steering Problems: If your ATV is hard to steer, check the power steering fluid level (if equipped). Inspect the tie rods and ball joints for wear. Check for play in the steering components. Worn tie rods and ball joints can affect steering. Replace any worn components to improve steering performance.

Troubleshooting Tips

When you're faced with a problem, don't panic. Take a systematic approach to troubleshooting. Here are a few tips:

• Start with the Basics: Check the easy stuff first, like fuel, spark, and air. These are the most common culprits.
• Consult the Manual: Your owner's manual is your best friend. It has detailed information about your ATV's systems and troubleshooting guides.
• Use the Right Tools: Make sure you have the right tools for the job. A good set of wrenches, sockets, a multimeter, and a compression tester are essential.
• Take Your Time: Don't rush the process. Take your time, and carefully diagnose the problem before you start making repairs.
• Watch Videos: YouTube is a goldmine of information. Search for videos on your specific problem. Seeing someone else fix it can be incredibly helpful.
• Safety First: Always disconnect the battery before working on electrical components. Wear safety glasses and gloves when appropriate.

Getting Your Hands Dirty: Repair Procedures

Okay, let's get into some specific repair procedures. Keep in mind that these are general guidelines, and you should always consult your owner's manual for specific instructions for your Polaris Sportsman 850. We will not be covering the entire repair process. Consult the manual and videos to have a better understanding.

Changing the Oil

1. Warm up the engine: Run the ATV for a few minutes to warm up the oil. This makes it flow more easily. Always turn off the ATV before starting the process.
2. Gather your supplies: You'll need the correct type of oil, an oil filter, an oil filter wrench, a drain pan, and a funnel. Get the proper tools and parts to avoid any issues during the process.
3. Locate the drain plug: Find the drain plug on the bottom of the engine. Place the drain pan under the drain plug. Remove the drain plug, and let the oil drain completely. Ensure that the ATV is level for a proper drain.
4. Remove the oil filter: Use the oil filter wrench to remove the old oil filter. Be prepared for a little more oil to spill out.
5. Install the new oil filter: Lubricate the rubber gasket on the new oil filter with fresh oil. Screw the new filter onto the engine by hand until the gasket makes contact, then tighten it according to the instructions on the filter. Make sure the filter is installed correctly to prevent oil leaks.
6. Replace the drain plug: Clean the drain plug and install a new crush washer (if needed). Tighten the drain plug to the specified torque. Avoid over-tightening the drain plug to prevent damage to the oil pan.
7. Add new oil: Use the funnel to add the correct amount of new oil to the engine. Check the oil level with the dipstick, and add more oil if needed. Overfilling the oil can be as harmful as under-filling it, so be precise.
8. Start the engine: Start the engine and let it run for a few minutes. Check for leaks around the drain plug and oil filter. The engine should run smoothly, and the oil pressure light should turn off.
9. Check the oil level again: After running the engine, turn it off and let it sit for a few minutes. Check the oil level again and add more oil if needed. Make sure that the oil level is within the appropriate range.

Changing the Air Filter

1. Locate the air filter: The air filter is usually located under the seat or in a compartment near the engine. Refer to your owner's manual for the exact location.
2. Remove the air filter housing: Unscrew or unclip the air filter housing cover. Remove the old air filter.
3. Inspect the air filter housing: Clean the air filter housing to remove any dirt or debris. Ensure the housing is clean to prevent contamination.
4. Install the new air filter: Install the new air filter in the housing. Make sure it fits properly. The filter must fit securely to prevent dirt from entering the engine.
5. Reassemble the air filter housing: Replace the air filter housing cover and secure it. Ensure the cover is properly sealed to protect the filter.

Parts and Tools

Having the right parts and tools makes repairs much easier. Here's a list of essentials:

• Service Manual: A good service manual is a must-have. It provides detailed diagrams, instructions, and specifications for your ATV. This is the first thing that you must acquire.
• Basic Hand Tools: Wrenches, sockets, screwdrivers, pliers, and a hammer. These are your everyday tools.
• Specialty Tools: You might need specialty tools like an oil filter wrench, a compression tester, a torque wrench, a multimeter, and a belt removal tool. Some repairs require special tools.
• Parts: Keep a stock of common parts on hand, like oil filters, air filters, spark plugs, and fuses. It is better to have the parts when they're needed.
• Protective Gear: Safety glasses, gloves, and a work surface are essential.

Where to Find Parts

Finding the right parts is essential for any repair. Here's where you can source parts for your Polaris Sportsman 850:

• Polaris Dealerships: The dealership is a reliable source for OEM (Original Equipment Manufacturer) parts. They can provide the specific parts your ATV needs. But the price may be expensive.
• Online Retailers: Websites like Amazon, eBay, and dedicated ATV parts retailers offer a wide selection of parts, often at competitive prices. You can save money and find parts easily. Be sure to check reviews and ensure the vendor is reputable.
• Local Auto Parts Stores: Some auto parts stores carry ATV parts, especially common items like oil filters and spark plugs. Check to see if they carry the parts that you need.
• Salvage Yards: If you're on a budget, salvage yards can be a good source for used parts. However, be sure to inspect the parts carefully before purchasing them.

Final Thoughts

Maintaining and repairing your Polaris Sportsman 850 doesn't have to be a daunting task. With a little knowledge, the right tools, and a systematic approach, you can keep your ATV running smoothly for years to come. Remember to always prioritize safety, consult your owner's manual, and don't be afraid to ask for help if you need it. There are tons of online forums and communities where you can find advice and support from other ATV enthusiasts. So get out there, enjoy the ride, and keep your Sportsman 850 in top shape! Ride on, guys!