Non of us can doubt the power of 2-stroke diesel engine. However, there are some common problems associated with this engine.
1. Engine runaway: If you are familiar with series 92 and 71 you will know what I mean by engine runaway. This usually occurs when you are adjusting the valve or the injectors. If the injectors are not properly adjusted, what you will notice is that the engine will runaway, which simply means the rpm of the engine will increase abnormally and the engine will refuse to stopped.
Should I tell you how to stop the engine? The answer is simple, just block the intake manifold of the engine to make it stop.
Another cause of this runaway in the 92 & 71 series is because of a bad governor. If the governor of the engine is bad, it will cause the engine speed to become unsteady.
2. Root blower pumps too much or too little air into the chamber: The root blower plays a significant role in the 92 & 71 series. It helps to direct the flow of air into the cylinder. It also ensures proper scavenging process to take place.
However, if the root blower supplies excess air into the cylinder it will result into loss of power because the fuel cannot combust all the air in the combustion chamber.
And in the event where the root blower also supplies lower air, it will also cause serious problems for the engine because the air supply is not sufficient to combust the available fuel in the combustion chamber.
3. Oil leakages: Oil leakages is another problem with 92 & 71 series. In most cases the oil leaks usually from the valve cover. The valve cover has a rubber seal to prevent the oil leaks, but if the seal is worn or not properly aligned on the cylinder head, then it will cause the engine to leak oil. That is why on most cases many mechanics decide to add sealant to the seal to prevent oil leaks.
4. Increase in noise: Another notable problem of the engine is increase in noise of the engine as the engine is gets old. Although it is a 2-stroke engine and naturally it is very loud, it becomes more noisier as it gets old. Several things have been done to fix that such as: valve adjustment, running on lower rpm, or overhauling the engine. No matter what you do, the noise will continue to increase.
5. Pulling liner: This is a problem that is very hidden. It simply means that when the engine is running, as the piston is traveling inside the cylinder, it causes slight movement of the sleeve in the engine block . For you to ascertain such a problem, you need remove the cylinder head, and manually rotate the engine.
Then you will notice that as you rotate the engine the liner pulls out gradually from the engine block.
6. Emulsification: Emulsification simply means that the coolant and the oil are mixing together. ThIS can be caused by numerous reasons such as leaking oil cooler, sleeve liner rubber, the cylinder head seals, or cranks on the engine.
These are the common problems of Detroit series 92 and 71.
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