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?

 

[TugboatEng]

Are you using OEM or aftermarket parts?

 

[LittleInch]

Some sort of contaminant in the gas?

what does Waukesha say?

 

[gruntguru]

Assuming factory parts and clearances, the sticking will most likely be the result of contamination buildup. Because you have a problem with both intake and exhaust valves I would look at your lubricating oil. Does it have adequate solvency to remove varnish-like contamination?

 

[dtimberlake]

Have the engines always done this?
Do they all have valves that stick?
How old are the engines?
Have you done oil analysis on engines whose valve(s) have stuck?
Do the valve(s) stick when in service, or when re-starting immediately after shut down , or when starting after sitting a week or 2?
Is it always both the intake and exhaust valves on the same cylinder?

When valve(s) stick what do you do?

1. Let the engine run on 3 or 5 cylinders, until the valve(s) un-stick.
2. Remove the cylinder head and repair it in your shop? What do they find, and what do they do to put the head back in service?
3. Send the head to a machined shop for repair? What do they find, and what do they do to put the head back in service?

Whoever removes the valves and inspects the valves and guides will be able to tell if the problem is deposits, scuffing and seizing, or etc.

I had a car once with "wet" cylinder liners that allowed a little coolant into the oil. The coolant reacted badly with the oil and deposits formed on the valve stems that kept the valves from seating until the engine warmed up for 10 minutes or so. Refer to Item 1. Above.

 

[TugboatEng]

A great way to end a conversation about troubleshooting engines is to start by asking about the source of the parts.

 

[dtimberlake]

OP ain't been back since the day of joining, and the post, Jan 8.

I guess the problem has been solved.

I would have liked to see some pictures of the freshly stuck/un-stuck valves and guides.

 

[TugboatEng]

As an I. As a fleet operator of diesel engines, the valve material technology is so good nowadays that we no longer do valve adjustments. We do valve checks. Any change in settings should be interpreted as a failure and dictate a cylinder head replacement. Stuck valves are never a problem with diesel fuel. Natural gas may include digester gas which is loaded with silanes. I know they accumulate on piston crowns. I don't know about valves. I don't burn digester gas.