Yanmar Engines

[klem]

I assumed that the whole discussion was based around running the engine in gear which is a load that increases with rpm. We should both be able to agree that once you bring up the rpms a significant amount from idle while in gear, you will be placing enough load on the engine to bring it up to temp. Even in neutral, you can bring up the temp enough by raising the idle sufficiently as proved by looking at coolant temp and egt's but that is a different debate.

I agree that stuck rings and glazed cylinders are real problems but they are due to low temperatures which will not be an issue in the situation that I described. I suspect that the reason that never monday and I disagree is that I made the assumption of being in gear and he may have been talking more generally. The issues brought up are a real concern for people who spend time charging batteries in neutral without doing something to raise their cylinder temps.

A lot of people in the sailing community claim that a diesel has to be run really hard for it to last. The reason that I posted earlier was that this simply is not true, you do need to put a load on it to keep the temperatures up but you don't need to run it like it is a rental. There is a wide range of rpms that you can operate the engine in while in gear and have no temperature related problems. I realize that most people do not watch the temp gauge like a hawk or have an egt gauge so it makes sense to be a little cautious. It is up to the operator to make the decision of how they want to use the engine and there is no magic about running the engine really hard which will make it last a lot longer so you should run the engine where you want provided that you are not idling around or taching it out.

[Adelie]

Originally Posted by never monday

Wet stacking is not common to these engines.

What is Wet stacking?

[never monday]

Originally Posted by Adelie

What is Wet stacking?

Wet stacking - Wikipedia, the free encyclopedia

[klem]

The explanation posted by never monday is good. A quick explanation is that the combustion temps are too low which results in not all of the diesel being burned. It is called wet stacking since you notice a wetness in the exhaust which is the unburned fuel. The danger of it is that it will coat parts inside the cylinder, valves, exhaust, and turbos. The way to prevent it is to make sure your combustion temps are high enough. Since boat diesels don't tend to have egt gauges, your best bet is to make sure the engine is under some load.