Low compression

[tbean]

DD 671tvi. Low compression in one cylinder. What are my options?

 

[Captain Ralph]

How do you know it low on compression? Or just a dead lung?
Any white smoke that does not clear when warm?
Or a cold exhaust from that lung?
Lots of crank case pressure?

You can rotate injectors from a good cylinder and check where the cold exhaust goes.

For a sudden loss, I find a valve has stuck or failed.
Valve cover off, check valve height to that lung.
You can pull a side cover and check the piston rings. with the piston down, a bore scope can look up and see the valves from the inside the lung.

If not an injector, the head comes off.

Where is your boat?

 

[SeaEric]

How well is it running? Is it making good power and not smoking too much at temp? IMHO Keep running it.

 

[Boatsb]

Why does it have low compression?

Karnak the mechanic is off today.

 

[JD5652]

DD 671tvi. Low compression in one cylinder. What are my options?

How low? What are the numbers? is it totally dead? It is limping along with fuel washing down the cylinder?

 

[Bob Bradley]

Valves properly adjusted?

 

[rsmith]

It’s either valve or rings. How low Is the compression? How do you know it has low compression? If you did a compression check you should already know whether it’s blowing by the valve or rings

 

[ageless]

anyone opened inspection ports? That could make your decision easy.