How to Troubleshoot a Briggs & Stratton 407777

Start the engine and allow it to run for a few minutes to warm up. Turn the engine off. Disconnect the spark plug and keep the spark plug wire away from the spark plug. Take the dipstick out of the oil fill tube and wipe it clean with a paper towel. Unscrew the oil drain plug and allow the engine oil into an approved oil collection container. When the engine oil reservoir is empty, reinstall the oil drain plug. Unscrew the oil filter and dispose of it according to local laws. Apply a small amount of fresh oil to the new oil filter gasket to help it create a good seal. Apply the oil filter to the engine until the gasket seats against the oil filter adapter, then turn it again ½ to ¾ turns. Be sure the engine is sitting level. Wipe the oil fill area clean with a paper towel to remove debris. Pour fresh 10W30 engine oil into the oil fill tube. This engine will hold 62 to 64 ounces of oil. After the oil has been added, wait for a minute and check the oil level with the dipstick. The oil level should be at the full (F) mark on the dipstick. Add more oil if needed. Replace the dipstick and tighten it.

Remove the spark plug with a spark plug tool. Check the electrode gap on a new spark plug with a spark plug gapping tool. The gap should be set to 0.030 inches. Install the new spark plug with a spark plug tool. Reattach the spark plug wire.

Drain the fuel tank into an approved fuel container. Squeeze the hose clamp tabs together with a pair of pliers to disconnect the fuel lines from the fuel filter. Slide the clamps down the hoses away from the fuel filter. Check the fuel line for cracks of fuel leaks and replace the fuel line if any problems are found. Attach the fuel lines to a new fuel filter. Slide the hose clamps towards the fuel filter to keep the hoses attached to the fuel filter.

Remove the air filter cover and remove the foam pre-filter and the air filter from their housing. If the air filter is really dirty or damaged, replace it with a new filter. Otherwise, tap the dirt off of the filter. Rinse the foam pre-filter out with warm water and mild dish soap. Allow the foam pre-filter to dry. Reinstall the filters and replace the air filter cover.