What is the valve clearance for Weichai Natural Gas P13?
2 Answers
The gap between the end of the valve stem and the components of the valve transmission group when the valve is fully closed is called the valve clearance. The size of the valve clearance is determined by the engine manufacturer through testing. Generally, in a cold state, the intake valve clearance is 0.25mm~0.35mm, and the exhaust valve clearance is 0.30mm~0.35mm. Hazards of excessive or insufficient valve clearance: 1. Too small: If the valve clearance is too small, the engine may experience air leakage due to improper valve closure in a hot state, leading to reduced power or even valve burning. 2. Too large: If the valve clearance is too large, it will cause impact noise between the transmission components and between the valve and valve seat, accelerating wear. At the same time, it will also reduce the duration of valve opening, worsening the cylinder's air intake and exhaust conditions.
The valve clearance for the Weichai natural gas P13 engine is generally set at 0.35 mm for the intake valve and 0.45 mm for the exhaust valve when cold. When I used to drive this type of vehicle, I often checked it myself because too small a clearance would increase engine noise, while too large a gap would affect acceleration response, especially during long-distance transport where fuel consumption could rise significantly. Every season change, I would measure it with a feeler gauge to ensure it stayed around 0.35 mm with a fluctuation of no more than 0.05 mm. If not adjusted in time, minor issues like severe shaking could occur, or worse, it might burn out the valves, leading to repair costs of thousands of yuan. Remember, the maintenance manual recommends checking every 50,000 km. Start the engine in a quiet place and listen for noise—if it sounds too sharp, it's time to check the clearance.