Valve Bridges Failure Analysis
Did you know that when the valves fail on your diesel engine, it could be due to a failure in a specific area of the valve? Different types of failure cause damage in different areas of the valve, so identifying where the failure occurred can help you diagnose exactly what's going on in your engine.
We're taking you through what happens to cause a failure in your valve bridges. Take a look at the images below to see if this is what's happening to you.
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Valve failure caused by turned valve bridge
Have you noticed that the valve head came off, damaging the cylinder kit and head? Below we go through how this can happen.
The first picture shows the valve head. The valve broke in the strongest part of the valve and not at the parting line between the valve head and stem. Breaks in this part of the valve occur when the valve is hit and the failure is caused by impact loading.




Conclusion: The most likely cause for the valve failure was found to be impact loading caused when the valve was momentarily locked in the open position by the turned valve bridge, allowing the piston to strike the valve, breaking it off from the stem.
Need more ideas of what might be going wrong with your valves? Check out our valves failure analysis.
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Originally Posted November 18, 2015; Edited March 13, 2020