What to do if there is water or dirt mixed in the fuel of my KYMCO Mongoose 90 Offroad Vehicle?
If there is water or dirt mixed in the fuel of your KYMCO Offroad Vehicle, clean the filter element and the fuel tank.
What to do if my KYMCO Mongoose 90 Offroad Vehicle has a wet plug with no spark?
If your KYMCO Offroad Vehicle has a wet plug with no spark, remove the plug and wipe it clean with a dry cloth. Also, adjust the plug gap or replace the plug.
How to resolve poor performance at low speeds in KYMCO Mongoose 90 Offroad Vehicle?
If your KYMCO Offroad Vehicle experiences poor performance, especially at idle and low speeds, the ignition timing may be off due to a faulty ignition unit, so check the ignition timing. The carburetor may be incorrectly adjusted; check the carburetor air screw adjustment. Also, inspect the carburetor gasket for air leaks, as a deteriorated O-ring or a carburetor that isn't securely tightened could be the cause. Remove the spark plug, install it into spark plug cap and test spark by connecting it to engine ground if the spark is good, weak or intermittent.
What to do if my KYMCO Mongoose 90 Offroad Vehicle engine turns over slowly?
If the engine of your KYMCO Offroad Vehicle turns over slowly, check the fluid, recharge the battery, and inspect the connections.
What to do if my KYMCO Offroad Vehicle has no fuel?
If your KYMCO Offroad Vehicle has no fuel, supply fuel.
How to fix a KYMCO Mongoose 90 that won't start?
If your KYMCO Offroad Vehicle engine won't start, it might be due to several reasons. First, ensure the fuel tank isn't empty and that fuel is reaching the carburetor by loosening the drain screw. Other potential causes include a clogged fuel line, float oil passage, fuel tank cap breather hole, fuel filter, or fuel valve passage. Also, the spark plug, ignition unit, or pulser coil might be faulty. A weak or dead battery could also be the culprit. To check the spark, remove the spark plug, install it into the spark plug cap, and connect it to the engine ground to test for a spark.
Why does my KYMCO Mongoose 90 Offroad Vehicle engine lack power?
If your KYMCO Offroad Vehicle engine lacks power, several factors could be responsible. A clogged air cleaner or restricted fuel flow could be the cause; try starting the engine and accelerating lightly to observe. The ignition timing might be off due to a faulty ignition unit or incorrect timing, so check the ignition timing using a timing light. Also, inspect the valve clearance, and test cylinder compression to identify issues such as improper valve and seat contact, worn cylinder and piston rings, or a leaking cylinder head gasket. Check the carburetor for clogging and inspect the spark plug for fouling or incorrect heat range.
What to do if KYMCO Offroad Vehicle is undercharging?
If your KYMCO Offroad Vehicle is undercharging, it could be due to a dead or faulty battery. Start the engine and test the limit voltage of the battery terminals. Alternatively, there may be a faulty A.C. generator coil, which can be checked by measuring the resistance between its terminals. Also, check for broken wires, such as a yellow or red wire. To check the red wire, connect the battery (+) wire to the regulator/rectifier coupler red wire and the battery (-) wire to engine ground, then test the voltage. Finally, a faulty regulator/rectifier may be the cause; inspect its coupler for loose connections.
What causes overcharging in my KYMCO Mongoose 90?
If your KYMCO Offroad Vehicle is overcharging, it could be due to a broken green wire. To check, connect the battery (+) wire to the regulator/rectifier coupler green wire and the battery (-) wire to the engine ground, then test the voltage. Another cause could be a poorly connected coupler or a faulty regulator/rectifier. Inspect the regulator/rectifier coupler for loose connections.
What to do if there is no spark at the spark plug in KYMCO Offroad Vehicle?
To troubleshoot a lack of spark at the spark plug in your KYMCO Offroad Vehicle, start by replacing the spark plug with a new one and inspecting again. Check the spark plug cap and high-tension wire for looseness. If those are good, check the CDI unit coupler for looseness. If the CDI unit coupler is normal, measure the resistance between the terminals of the CDI unit coupler. If it's still normal, check related parts. If the CDI unit or ignition coil are abnormal, check them with a CDI unit tester.
General| Brand | KYMCO |
|---|---|
| Model | Mongoose 90 |
| Category | Offroad Vehicle |
| Language | English |
States the ATV is for off-road use only and must comply with noise regulations.
Defines the warning, caution, and note symbols used in the manual.
Explains the functions of the ignition switch positions (OFF, ON).
Explains the engine stop switch functionality and safety note.
Warns about throttle malfunction causing accidents.
Warns about improper speed limiter adjustment causing accidents.
Instructions for setting and unlocking the parking brake.
Warns about risks of not applying/releasing parking brake correctly.
Covers checks for brakes, fuel, oil, chain, throttle, tires, fittings, switches, and lights.
Details checks for drum & disk brakes, including free play and fluid.
Ensure sufficient fuel and check for leaks. Fuel level below filler neck.
Warns that riding with faulty brakes can lead to accidents.
Warns about fuel spills causing fire and injury; advises careful refueling.
How to check oil levels and recommended oil types.
Lists approved tire sizes and recommended pressures.
Warns against operating without understanding controls.
Lists steps for starting a cold engine, including brake, fuel, ignition, and tether lead checks.
Explains choke usage based on ambient temperature for cold starts.
Steps for parking: stop engine, turn fuel OFF, apply parking brake.
Warns about ATV rolling out of control when parked on slopes.
Instructions for parking on slopes: position transversely, apply brake, block wheels.
Reinforces age limits and supervision requirements for young riders.
Warns that operating without instruction greatly increases accident risk.
Always perform pre-operation checks before riding for safety and care.
Modifying the ATV can render it unsafe/illegal; avoid altering exhaust or emission systems.
Mandates wearing helmets, eye protection, gloves, boots, and proper clothing.
Warns against operating the ATV after consuming alcohol or drugs due to impaired judgment.
States the machine is designed for operator only; carrying passengers is prohibited.
Warns against riding on paved surfaces as it affects handling and control.
Prohibits riding on public streets, roads, or highways due to collision risk.
Keep feet on footboards; otherwise, they may contact rear wheels.
Warns against operating too fast for skills or conditions, risking loss of control.
Warns against attempting stunts like wheelies or jumps, which can cause accidents.
Ride cautiously in unfamiliar areas, stay alert for hidden hazards.
Warns that the exhaust system is hot and can cause burns. Avoid touching.
Warns that improper turning can cause loss of control or overturn.
Warns about overturning on excessively steep hills.
How to restart safely or dismount if stalled on a hill.
Do not use rear brake if rolling backward; dismount uphill. Apply front brake.
Warns about operating with improperly serviced brakes; requires professional knowledge.
Warns brake fluid can irritate skin or eyes; flush with water if exposed.
Warns about open flames/sparks near the battery causing explosion.
Warns against using improper fuses, which can cause damage or fire.
Warns against smoking or open flames when checking the fuel system.
Warns about reduced stopping ability of wet brakes after washing.
Warns about refueling hazards: fire, explosion, spills.
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