internal combustion engine stuck valves

[Luis_Villacres]

We own natural gas engines (Waukesha), sometimes the exhaust/intake valves were stuck in the valve guides, Do you guys know the causes and solutions to solve that issue?

 

[mfgenggear]

As said before, tear down and Inspect, but I have not worked on these engines .
Is there a procedure like gas engine . Edit
Removed comment.
Inspect with bore scope

 

[gruntguru]

The first thing that should be done after a failure like that is to measure valve stem diameter and valve guide bore diameter and compare to specification.
I assume this was done.
What were the results?
If clearance is less than it was when it was last assembled you have contaminant buildup.
Are these engines lean-burn or stoichiometric?

 

[TugboatEng]

There may be a clue here. Rusty ports are an abnormal condition.