Introduction
A diesel engine is one of the most necessary components of a variety of engines, ranging from the small ship engines to those powering the massive locomotives. In order to keep these engines working properly and efficiently, regular maintenance is essential. One of the most important tasks for keeping a diesel engine running is to adjust the various valves that control the airflow and mixing of air and fuel. These valves, when properly adjusted, allow the engine to breathe properly and use fuel and air as efficiently as possible.
Valve Adjustment Overview
Valve adjustment, also known as valve lash adjustment or valve lash setting, is the process of adjusting the distance, or “lash”, between the valve stem and the connecting rocker arm or cam follower. This distance, known as the “valve clearance”, must be set to a specific value in order to allow the valve to open and close properly while the engine is running. Improper valve clearance can cause the valve to stick, resulting in low compression and reduced power output.
Valve Adjustment Procedure
The procedure for valve adjustment is relatively simple, but it is important to take the time to adjust all of the valves in a particular engine, as each engine and type of diesel engine will have different valve requirements. In general, the procedure is as follows:
1. Remove the exhaust and intake manifolds and identify the valves. Electronic valve actuation systems may require that the valve covers be removed, although most manufacturers now use hydraulic or mechanical valve actuation systems, which require no disassembly or replacement of components.
2. Locate the proper adjustment points for the intake and exhaust valves. This will usually involve loosening and rotating a small nut or bolt at the point where the valve stem meets the connecting rocker arm or cam follower.
3. Measure the current clearance between the valve stem and the rocker arm or cam follower. This distance should be equal to the manufacturers specifications for the operating temperature of the engine. If the clearance is too large, the valve will not open and close properly, resulting in a lack of power and reduced efficiency.
4. Rotate the adjustment nut or bolt until the correct clearance is achieved. This can involve adjusting multiple valves in the same engine, so it is important to be precise in order to ensure proper operation.
5. Once the adjustments have been made, they should be rechecked to ensure that they are correct. If any valves require further adjustment, the procedure should be repeated until the correct clearance is obtained.
Conclusion
Valve adjustment is a critical component of regular maintenance for diesel engines. This process should be performed regularly in order to ensure that the engine is running as efficiently and effectively as possible. Failure to properly adjust the valves can lead to reduced performance, increased fuel consumption, and other problems. By following the simple steps outlined above, anyone can adjust the valves on a diesel engine, ensuring that it will remain reliable and powerful for years to come.
