Engine Diagnosis in Heavy Vehicles and Machinery


Sydney Truck Electrical has over 20 years’ experience in the truck repair industry. In our experience, the most common faults in heavy vehicles are those concerning the engine. There are a range of issues faced by commercial vehicle drivers and heavy machinery operators when it comes to the engine. A few common engine problems are listed below.

Oil Oxidisation and Water Contamination

If diesel heavy commercial vehicles sit in one place for too long air bubbles can get into the oil supply. Air bubbles can interfere with lubrication of moving components which can result in faltering. Engines can quickly become damaged in this situation.

The same problem can arise with water too. If an engine is standing still in a humid environment, water can cause the engine to knock. It can also hinder the lubrication process. In these cases, the oil needs to be changed by us.

Faulty Fuel Injectors

When the balance of fuel to air is sub-optimum in a diesel engine it can lead to black exhaust. This happens when there is too much fuel and not enough air in the fuel supply. This can pose a serious health risk to those in the cabin.

Heavy fines may also ensue according to clean air regulations in NSW. Replacing the faulty injector, injector pump, air filter, EGR valve or even turbocharger can fix the root of this problem.

Hard Starting

It’s quite common for diesel engines to crank a little when you start them prior to departure. However, a consistently hard start can be a sign that the vehicle’s engine is damaged.

Before calling us, check your fuel levels, oil temperature and battery level. If these metrics all look okay, call us immediately. We’ll have to replace the solenoid or ignition switch.

Power Problems

There are several reasons why a diesel-powered vehicle may experience problems related to its power supply. Dirty fuel filters, a loose throttle connection or issues with fuel injectors can put unnecessary strain on the battery. You’ll notice these problems when the vehicle has trouble accelerating.

If the lead-acid storage battery doesn’t work properly then hard starting can also result because of an imbalanced compression ratio.

High Compression Ratios

The average diesel engine has a compression ratio of 20:1. This means the volume of the cylinder and combustion chamber when the piston is at the top compared to the bottom is 20:1.

This high ratio makes the engine run more smoothly, with more power, but can also lead to issues. One example is a knocking engine as fuel is burnt inefficiently. You may need a new cylinder if this has happened to you.

Our top-of-the-range diagnostic equipment allows us to provide a rapid diagnosis and quality repairs to any engine problems we encounter. Please contact Sydney Truck Electrical today for a rapid call-out, diagnosis and solution. We will diagnose and repair faults with a high level of precision. Our truck mechanics perform truck repairs and maintenance on heavy vehicles and other machinery anywhere in Sydney.