How to test the engine of used construction machinery such as excavators and wheel loaders

First of all, I would like to say that most of the large suppliers of used equipment are not scammers. But, as the Germans say, “exceptions check the rules.” And what’s better than expecting the engine to be good? It is better to know it.

If you arrive at the site and inspect a used construction machine with a wheel loader, excavator, bulldozer, or other combustion engine, we recommend the following steps:

• Make sure the engine is cold before turning the key. If it has already warmed up, this may indicate a problem with the cold engine (compression).
• Check the oil condition. Having new oil and old air and fuel filters and no other service is a bad sign.
• Then open the cooler reservoir and check the quality of the coolant. It should not contain ordinary water and the coolant should be more or less clear. It should not smell diesel and should not contain petroleum.
• Leave the cooler reservoir open to start the engine. Look at the smoke at the start. A little gray or black smoke should disappear after a maximum. 30 seconds
• Monitor the cooler reservoir or place your hand in the opening. There should be no pressure. Now you can close it.

Next, check the so-called blow-by. When the engine is running, a certain amount of pressure from combustion bypasses the pistons and piston rings and reaches the crankshaft case. Therefore, a vent line exists and is accessible to most engines. (In some modern engines, this hose returns to the air inlet channel to return the gas to the engine.)

To check the blow-Open the oil filler cap and place your hand. It is difficult to explain the level of blow-by allowed. But to give you a feeling: blow through your nose with your hands. If the engine wear level is normal, it should be less. The engine must run idle! The oil filler cap should not be covered with gray residue. This is a sign of watering the engine oil.

You can now run other machine tests such as stall tests and cycle time tests. This warms the engine to operating temperature. Run the engine at operating speed and observe the smoke. Under load, a little black smoke will be normal. If the fuel does not burn completely, more black smoke will be produced. Blue smoke indicates that the fuel is mixed with oil somewhere before it burns. Unburned fuel that enters the exhaust gas is the cause of white smoke.

After running the engine for 20 minutes, you can look back. Take the flashlight and watch out for leaks.

If you’re not sure if you can perform these tests, don’t have time to travel, or just want to offer this job to a professional, call a company like this: MEVAS To have the machine inspected. The author of this article runs a used equipment appraisal business and has many years of experience in equipment inspection.