Engine Overhaul of LIEBHERR D924 T-E in LTM 1150-5.1 Crane

Engine overhaul Liebherr D924 T-E in the mobile crane LTM 1150-5.1

The Liebherr LTM 1150-5.1 mobile crane is an advanced machine used in construction, industrial assembly, and tasks requiring high lifting capacity and mobility. Equipped with a Liebherr D924 T-E diesel engine with a power of approximately 120 kW, it provides adequate power for performing heavy tasks. In our service in Kojszówka, we carried out a complete overhaul of this engine after reporting issues with its operation. The order included comprehensive diagnostics, disassembly, verification, repair, and reassembly of the power unit along with tests on the dynamometer.

Preliminary diagnostics – reason for the overhaul

The machine was reported to our mobile service due to loss of power and excessive smoking. During operation, the operator noticed problems with maintaining revolutions and difficulties in starting. Preliminary diagnostics indicated burnt valves, which was confirmed after performing compression tests and checking the cylinder sealing. Additionally, an endoscopic camera was used to inspect the combustion chamber. After diagnosing the problem, it was decided to disassemble the unit and transport the engine to our facility in Kojszówka.

Engine disassembly

The disassembly of the D924 T-E engine from the Liebherr LTM 1150-5.1 crane was carried out by our mobile service team on-site at the client's location near Katowice. According to the procedure, the client's crane was used to safely remove the unit from the machine compartment. The process included disconnecting fuel, hydraulic, and electrical lines, as well as the intake and cooling systems. All ends of the lines were secured to prevent contamination and leakage of operating fluids. After separating the engine from the frame, it was loaded onto specialized transport and delivered to our workshop.

Verification of components

In the workshop, the engine was completely disassembled, and each component was thoroughly inspected. Wear of the valve seats and leakage of several valves in the head were confirmed. The crankshaft and connecting rods were inspected for cracks and wear. Pistons, rings, and cylinder liners were also checked. The fuel system was disassembled and sent for testing to an external facility specializing in the regeneration of pumps and injectors. Additionally, the turbocharger was subjected to tests for axial and radial clearances.

Regeneration and repair

The repair process included planning the head, replacing valve guides and the valves themselves. Cylinder liners were replaced with new ones, as well as piston rings and crankshaft bearings. The crankshaft was ground and rebalanced after measurements. The injection pump was regenerated, and the injectors achieved factory parameters after testing. The turbocharger was regenerated, and the starter and alternator were also replaced to eliminate potential problems in the future.

Engine assembly

After completing all regeneration work, we began the assembly process of the unit. Special attention was paid to the installation of the air piping and cooling system. All seals, lines, and clamps were replaced with new ones. During the assembly of the engine, tightening torques were applied in accordance with the manufacturer's service documentation. After assembly, the engine was mounted on the dynamometer for testing. After completion, the service team transported the unit back to Katowice, where it was installed in the crane. The installation included connecting systems, replacing filters, filling with fresh oil and coolant. The first tests were conducted with the participation of the machine operator, allowing for real-time verification of the engine's performance in working conditions.

Dynamometer testing

WIBAKO, as one of the few companies in Poland, has its own engine dynamometer. This allows every repaired engine to undergo a series of tests in controlled conditions. The Liebherr D924 T-E engine was started on the dynamometer after the overhaul and operated for a minimum of 16 hours under partial load (20-30% of nominal power). It was then subjected to full load tests multiple times to verify its power, torque, and operational stability parameters. As a result, the client received a fully tested unit ready for further operation. The dynamometer allows us to eliminate the risk of hidden defects and guarantees the highest quality of the overhaul.

Engine maintenance after overhaul

After the overhaul, the engine was covered by a warranty. We recommended the client to perform the first inspection after 50 operating hours, which includes replacing filters and checking all connections. Subsequent inspections are recommended every 250 operating hours, but no less than once every 3 months. Our mobile service offers support both in Poland and abroad, ensuring that the client can be confident that their machine will remain in full working order.

Liebherr D924 T-E engine – applications

The D924 T-E engine is a unit commonly used not only in Liebherr mobile cranes but also in other construction machines of this brand, such as loaders and excavators. Due to its high durability and efficiency, it is used in equipment where reliability and power are crucial.

Summary

The overhaul of the Liebherr D924 T-E engine in the LTM 1150-5.1 mobile crane restored the full functionality of the machine and ensured its long-lasting, reliable operation. Thanks to our own engine dynamometer and an experienced team of service technicians, WIBAKO guarantees the highest quality of services. The client received assurance that their equipment would operate efficiently, and every inspection would be carried out according to service recommendations.

What we do as part of the service

What the repair process looks like