# How to Diagnose a Construction Machine Engine? A WIBAKO Guide

> Discover how to diagnose and prevent costly repairs of a construction machine engine. Learn about common problems, the importance of oil pressure, and the role of diligent service. Understand how to handle difficult start-ups, leaks, and other engine issues. Equip yourself with knowledge to avoid equipment immobilization and financial losses.

### This topic is often the most common cause of a machine operator's headache.

Incorrectly identified engine faults can lead to a very costly breakdown, which in turn results in **equipment immobilization** and serious financial losses. How to diagnose a **construction machine engine** and whether all engine ailments are always associated with a very costly repair? We invite you to our guide.

![engine after repair](https://wibako.com/media/articles/article-138/b-46830-1.webp)

### Oil pressure - technical documentation will be useful

The most common problems with the engine of a construction machine related to difficult start-up, leaks, leaks and strange noises. **None of these signs should be underestimated!** The fault may be associated with a minor neglect, but equally well with the need to call a specialist service.

What you should always start diagnosing the engine with is **checking the oil pressure**. There may be some **trouble** with this, as the correct values vary depending on the **specific engine**.

In many cases, the minimum oil pressure oscillates around the value of 1 bar, for example two quite popular cases - the first is Liebherr brand combustion engines, which require a minimum value of 1.5 bar.

The second example is the quite popular Cummins unit with a capacity of 5.9 liters, which requires pressure above 0.8 bar, where in Liebherr machines at such a value we already have a critical state.

If you do not know how to diagnose the engine of a construction machine in terms of oil pressure, refer to the technical documentation of the device.

![combustion engine in the workshop](https://wibako.com/media/articles/article-138/b-wibako-3.webp)

### Diligent service is the basis

No decent engine should suffer a **sudden and costly breakdown**. The reality, however, is that there is a lack of time for **diligent inspections** on a daily basis. Hence the later problems.

So if we notice, for example, that the engine starts to **smoke black**, let's start by checking the basic elements, starting with the air filter. A clogged one can give such an effect. In addition, smoking can be caused by a faulty injection pump, faulty injectors, a faulty timing system.

So let's remember to regularly check all, even basic elements of the engine and its equipment. In many situations, this will avoid costly repairs.

### How to diagnose a construction machine engine that is not working well?

The most common problems with the engine concern **difficult start-up**. This can be caused by a **failure of the fuel system**, but equally well by wear of the injection pump or clogged fuel and air filters. A common cause is also simply **contaminated fuel**.

If the engine is not working well after starting and lacks power, it is worth looking for **leaks** in the fuel system. In more complicated cases, you need to look at the condition of the **turbocharger** or **gas controller**. A similar effect will also give a leak in the intercooler.

When the engine suddenly dies after starting and working for a short while, it may indicate **airing** of the fuel system or clogging of one of the filters.

If diagnostics confirm serious wear, we will carry out a full [combustion engine overhaul](https://wibako.com/services/overhauls-of-combustion-engines).

Published: 2024-03-26

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Source: https://wibako.com/about-us/blog/138-how-to-diagnose-a-construction-machine-engine-a-wibako-guide
Contact: +48338704200, biuro@wibako.pl