How much oil does my 139 four-stroke gasoline mower need?

Due to the different brands and models of lawn mowers, the refueling methods may be different. When refueling, you don't need to pull out all the plastic threads in the lid, just add them directly. Just add the right amount of gas, not too much.

139 is a four-stroke mower. The four-stroke machine is filled with oil and gasoline respectively. Generally, gasoline is not a big problem. If you add oil, you must follow the scale of the oil card, not lower than the scale of the oil card or higher than the scale. If you add oil halfway, it won't pull the cylinder, and if you add too much, it will suffocate the machine.

Note: The dynamic changes of intake and exhaust valves are as follows:

1. Excessive clearance: After the intake and exhaust valves are opened late, the intake and exhaust time is prolonged, the valve opening height is reduced, and the normal valve timing is changed, so that the power of the starter is reduced due to insufficient intake and unclean exhaust. In addition, the impact of valve train parts is increased and the wear is slowed down.

2. The clearance is too small: after starting the engine task, the parts shrink due to heat, pushing the valve open, resulting in the valve not being closed tightly, resulting in air leakage, power reduction, serious carbon deposition or burns on the valve sealing surface, and even the valve hitting the piston.

3. The exhaust valve clearance is actually about +0.005mm larger than the intake valve due to its thermal shrinkage.

At first, as long as the positioning points of crankshaft and cam match, it is not difficult to adjust the valve, and it only takes several debugging to get started.