That sinking feeling when your Polaris Predator 90 refuses to start, especially when your young rider is eager to hit the trails, is something most parents can relate to. The kick start on these little ATVs, while seemingly simple, can be a source of frustration. But don't despair! Understanding the potential causes of a stubborn kick start and knowing how to troubleshoot them can save you time, money, and a whole lot of headaches. This article will walk you through the common culprits behind Predator 90 kick start issues, offering practical advice and solutions to get your ATV purring again.

Why Won't My Predator 90 Kick Start? Unmasking the Usual Suspects

The Polaris Predator 90 kick start system is relatively straightforward, but several factors can prevent it from working correctly. Before you start tearing things apart, let's look at the most common problems:

  • Compression Issues: This is often the primary suspect. Without proper compression, the engine can't draw in fuel and air, preventing combustion. Low compression can be caused by worn piston rings, a damaged cylinder, leaky valves, or a blown head gasket.

  • Fuel Delivery Problems: Even with good compression, the engine needs fuel. A clogged carburetor, a blocked fuel line, or a malfunctioning fuel petcock can starve the engine and prevent it from starting.

  • Ignition System Woes: A healthy spark is crucial for igniting the fuel-air mixture. A faulty spark plug, a weak coil, or a problem with the CDI (Capacitor Discharge Ignition) unit can all lead to ignition problems.

  • Kick Start Mechanism Itself: The kick start lever engages a series of gears that turn the engine over. If these gears are worn, damaged, or improperly lubricated, the kick start may slip, bind, or fail to engage the engine.

  • Incorrect Starting Procedure: Believe it or not, the way you kick start the ATV can make a difference. Using the choke properly, applying the throttle correctly, and using a full, strong kick are all important.

Diagnosing the Dreaded Kick Start Failure: A Step-by-Step Guide

Okay, so you know the potential problems. Now, let's get down to diagnosing the specific issue plaguing your Predator 90. Here's a methodical approach:

  1. The Obvious Checks First:

    • Fuel: Make sure there's fuel in the tank. It sounds silly, but it happens!
    • Fuel Petcock: Ensure the fuel petcock (the valve that controls fuel flow from the tank) is open (usually in the "ON" or "RES" position).
    • Kill Switch: Double-check that the kill switch is in the "RUN" position.
    • Spark Plug Wire: Make sure the spark plug wire is securely attached to the spark plug.

  2. Testing for Spark:

    • Remove the spark plug.
    • Reattach the spark plug wire to the spark plug.
    • Hold the spark plug against the engine block (grounding it).
    • Kick start the engine.
    • Observe the spark plug tip. You should see a strong, consistent blue spark. A weak, yellow spark or no spark indicates an ignition system problem.

  3. Checking for Fuel Delivery:

    • Spark Plug Condition: Remove the spark plug and examine it. A wet spark plug indicates that fuel is reaching the cylinder, while a dry spark plug suggests a fuel delivery problem.
    • Carburetor Drain: Locate the drain screw on the bottom of the carburetor. Loosen the screw and see if fuel flows out. If no fuel flows, the carburetor may be clogged or the fuel line is blocked.
    • Fuel Line Inspection: Check the fuel line for kinks, cracks, or blockages. Replace the fuel line if necessary.

  4. Assessing Compression:

    • Thumb Test: Remove the spark plug and place your thumb over the spark plug hole. Have someone kick start the engine. You should feel strong pressure pushing against your thumb. Weak or no pressure suggests low compression.
    • Compression Tester: For a more accurate assessment, use a compression tester. Screw the tester into the spark plug hole and kick start the engine several times. Note the reading on the tester. A healthy Predator 90 should have a compression reading of around 120-150 PSI (pounds per square inch). Anything significantly lower indicates a compression problem.

  5. Inspecting the Kick Start Mechanism:

    • Feel and Sound: Pay attention to the feel and sound of the kick start lever as you kick it. Does it feel smooth, or does it feel rough, grind, or slip?
    • Visual Inspection: If you suspect a problem with the kick start mechanism, you may need to remove the side cover to inspect the gears and components. Look for worn, damaged, or broken parts.

Tackling the Troubles: Solutions for Common Kick Start Problems

Now that you've identified the problem, let's explore some solutions:

  • Spark Issues?

    • Replace the Spark Plug: This is the easiest and cheapest first step. Use the correct spark plug specified in your owner's manual.
    • Check the Spark Plug Wire and Cap: Make sure the wire is securely connected to the coil and the spark plug cap is in good condition. Replace them if they are damaged or corroded.
    • Test the Coil: Use a multimeter to test the coil's primary and secondary resistance. Refer to your owner's manual or a repair manual for the correct resistance values. Replace the coil if it fails the test.
    • Consider the CDI Unit: If the coil and spark plug are good, the CDI unit may be the culprit. Replacing the CDI unit is usually the best course of action.

  • Fuel Delivery Problems?

    • Clean the Carburetor: This is often the solution to fuel delivery problems. Disassemble the carburetor and clean all the jets and passages with carburetor cleaner. Pay close attention to the pilot jet, which is responsible for idle and low-speed fuel delivery.
    • Clean or Replace the Fuel Filter: A clogged fuel filter can restrict fuel flow. Clean or replace the fuel filter as needed.
    • Check the Fuel Tank Vent: A blocked fuel tank vent can create a vacuum in the tank, preventing fuel from flowing. Make sure the vent is clear.

  • Compression Woes?

    • Check the Valve Clearance: Incorrect valve clearance can cause low compression. Adjust the valve clearance according to the specifications in your owner's manual.
    • Inspect the Cylinder and Piston: If the valve clearance is correct, the next step is to inspect the cylinder and piston for wear or damage. This may require removing the cylinder head and cylinder. Look for scratches, scoring, or excessive wear.
    • Check the Piston Rings: Worn piston rings are a common cause of low compression. Replace the piston rings if they are worn or damaged.
    • Inspect the Head Gasket: A blown head gasket can also cause low compression. Look for signs of leaks around the head gasket. Replace the head gasket if it is damaged.

  • Kick Start Mechanism Issues?

    • Lubricate the Mechanism: Start by lubricating the kick start mechanism with a good quality grease. This may be enough to solve minor binding or slipping issues.
    • Replace Worn Parts: If lubrication doesn't help, you may need to replace worn or damaged parts, such as the kick start gear, ratchet, or spring.

Kick Start Technique: Mastering the Art of the Kick

Even with a perfectly functioning ATV, a poor kick start technique can prevent the engine from starting. Here are some tips:

  • Use the Choke: When the engine is cold, use the choke to richen the fuel mixture.
  • Prime the Engine (If Applicable): Some Predator 90 models have a primer button. Use the primer button to inject a small amount of fuel into the carburetor.
  • Find Top Dead Center (TDC): Slowly push the kick start lever down until you feel resistance. This is TDC.
  • Full, Strong Kick: Release the kick start lever and give it a full, strong kick. Avoid short, weak kicks.
  • Throttle Control: Avoid giving the engine too much throttle while kick starting. A small amount of throttle may be helpful, but too much can flood the engine.

Preventing Future Problems: Maintenance is Key

The best way to avoid kick start problems is to perform regular maintenance on your Predator 90. Here are some tips:

  • Regular Oil Changes: Change the oil regularly according to the manufacturer's recommendations.
  • Clean the Air Filter: A clean air filter ensures proper airflow to the engine.
  • Inspect and Clean the Spark Plug: Regularly inspect and clean the spark plug. Replace it as needed.
  • Use Fresh Fuel: Avoid using old or stale fuel.
  • Store the ATV Properly: When storing the ATV for an extended period, drain the fuel from the carburetor and fuel tank.

Frequently Asked Questions (FAQ)

  • Why is my kick start lever stuck? The kick start lever may be stuck due to rust, corrosion, or a damaged mechanism. Try lubricating the mechanism or disassembling it to inspect for damage.
  • My kick start slips, what does that mean? Slipping usually indicates worn gears or a faulty ratchet mechanism within the kick start system. Inspect and replace any damaged components.
  • How often should I change the spark plug? It is recommended to change the spark plug every 6 months or 50 hours of riding, whichever comes first.
  • What type of fuel should I use? Use unleaded gasoline with an octane rating of 87 or higher.
  • Where can I find a repair manual for my Predator 90? You can find repair manuals online or at your local Polaris dealer.

Final Thoughts

Troubleshooting a Polaris Predator 90 kick start problem can seem daunting, but with a systematic approach and a little patience, you can usually diagnose and fix the issue yourself. Remember to start with the simplest checks first, and don't be afraid to consult your owner's manual or a repair manual for guidance. Regular maintenance and proper kick starting technique will help prevent future problems and keep your little rider enjoying the trails for years to come!