Honda GX630 2014 Owner's Manual
![Honda GX630 2014 Engine manual cover](/images/CXLJIEOfWDPmlQzromkwPYkY/thumbs/thumb175x175.webp)
To perform an oil change, warm up the engine, turn it off, and disconnect the spark plug wire. Place an oil pan under the engine, remove the oil drain plug, and let the oil drain completely. Replace the drain plug, remove the oil filler cap, and add the recommended oil type until it reaches the appropriate level.
The recommended spark plug for the Honda GX630 engine is the NGK BPR6ES or equivalent. Ensure it is properly gapped before installation.
If the engine won't start, check the fuel level, ensure the fuel valve is on, and inspect the spark plug for wear or damage. Make sure the choke is in the correct position and the battery is charged if it's an electric start model.
The Honda GX630 engine should use unleaded gasoline with a pump octane rating of 86 or higher. Avoid using fuel with more than 10% ethanol.
The air filter should be checked every 50 hours of operation and cleaned or replaced if necessary. Replace the air filter every 200 hours or annually, whichever comes first.
To adjust the valve clearance, remove the valve cover and rotate the engine to the top dead center on the compression stroke. Use a feeler gauge to check the clearance and adjust using the adjustment nuts to the specified intake and exhaust clearances. Reinstall the valve cover when done.
Regularly check the engine cooling fins and clean them to remove dirt and debris. Ensure the engine is not operating in a restricted area that can cause overheating.
Symptoms of a clogged carburetor include the engine running roughly, experiencing power loss, or not starting at all. Cleaning or rebuilding the carburetor can often resolve these issues.
To winterize the engine, add a fuel stabilizer to the fuel tank, run the engine for a few minutes to circulate the stabilizer, then turn it off. Drain the carburetor bowl, change the oil, and remove the spark plug to add a few drops of oil into the cylinder. Reinstall the plug and store the engine in a dry place.
For extended storage, clean the engine thoroughly, drain the fuel system, change the oil, and remove the battery if applicable. Store the engine in a dry, sheltered location, and cover it to protect it from dust and debris.