Honda TRX420FM1 4X4 FourTrax Rancher 2018 Manual
![Honda TRX420FM1 4X4 FourTrax Rancher 2018 ATV manual cover](/images/dfNWFEMqQJSOfRGeFXMhoDbu/thumbs/thumb175x175.webp)
For optimal performance, use SAE 10W-30 motor oil that meets the JASO T 903 standard. Make sure it is suitable for wet clutches.
It is recommended to change the oil every 100 hours of operation or at least once per year, whichever comes first.
The recommended tire pressure is 4 psi for the front tires and 3 psi for the rear tires.
First, check the battery connections for tightness and corrosion. Ensure the fuel valve is on, and verify there is fuel in the tank. If the problem persists, inspect the spark plug for signs of wear or damage.
Stop the engine immediately and let it cool down. Check the coolant level and ensure the radiator is not blocked. If needed, top up the coolant and verify the fan is functioning correctly.
Regularly inspect the brake pads for wear and replace them if necessary. Ensure the brake fluid is at the correct level and free from contamination. Adjust the brake lever free play as needed.
Remove the air filter and wash it in warm soapy water. Rinse and let it dry completely. Lightly oil the filter with air filter oil before reinstalling.
Loosen the rear axle nuts and adjust the chain tensioner bolts until the chain has about 1 inch of slack. Tighten the axle nuts securely after adjustment.
Regular maintenance, such as keeping the air filter clean, ensuring proper tire pressure, and using the recommended oil, can help improve fuel efficiency. Avoid carrying unnecessary weight and maintain a steady speed when possible.
Unusual noises could be due to loose parts, worn components, or lack of lubrication. Inspect the ATV for any loose bolts, check the condition of the drive chain, and ensure all moving parts are properly lubricated.