Engine Overhaul of D924 TI-E A4 in LTM 1090-4.1 Crane

Overhaul of the D924 TI-E A4 Engine in the LTM 1090-4.1 Mobile Crane

Recently, our team performed a comprehensive overhaul of the D924 TI-E A4 engine (approx. 149 kW) in an LTM 1090-4.1 mobile crane. This machine, manufactured by the renowned brand :contentReference[oaicite:0]{index=0}, is one of the more popular mobile cranes used in construction and industrial work, known for its high reliability and versatility. The D924 TI-E A4 is a diesel engine with excellent efficiency, but like any combustion engine, it requires regular diagnostics and periodic servicing, especially under intensive use.

The need for an overhaul arose from natural wear and tear, including crankshaft and connecting rod bearing wear, which manifested as a drop in oil pressure and the appearance of metal particles in the oil filter. Our mobile service team traveled to Kraków, where the crane was in use, and then transported the engine to our facility in Kojszówka for full diagnostics and overhaul work.

Work Stages

Engine Disassembly

The engine disassembly was performed using a crane provided by the client. Technicians secured all cooling system components, intake air hoses, and accessories, then disconnected the engine mounting bolts and proceeded to extract it from the engine compartment. The process also included disconnecting all electrical wiring, fuel connections, and control elements to ensure safe transport to the workshop.

Component Inspection

After disassembling the engine, a detailed inspection of all components was carried out. The crankshaft was visually checked for cracks and overheating, and its runout was measured. Connecting rods and bearings were inspected for wear and possible deformation. The cylinder head underwent a leak test in a water bath with compressed air connected, while the turbocharger and injection pump were thoroughly inspected and bench-tested. This process allowed us to identify all areas requiring repair and prepare a regeneration plan.

Rebuilding and Repair

The crankshaft-piston assembly underwent a complete rebuild, including replacement of bearings, pistons, and rings, as well as inspection of the cylinder liners. The cylinder head was refurbished by replacing valve guides, valves, and checking for tightness. The injection pump and injectors were tested and calibrated, while the turbocharger was checked for clearances and worn components were repaired. After refurbishment, all parts were carefully cleaned and prepared for assembly.

Engine Assembly

Engine assembly was carried out according to strict service standards. Technicians carefully installed the engine in the crane, replaced all air hoses, checked connection tightness, and ensured proper mounting of all accessory components. An initial start-up was performed in the presence of the operator, verifying operating parameters, absence of leaks, and engine stability. The assembly process was thorough and included verification of all supporting systems.

Engine Dynamometer Test

After assembly, the D924 TI-E A4 engine was tested on our engine dynamometer, allowing precise analysis of performance under load conditions. The test lasted at least 16 mth under light load, followed by full load testing up to 100% of nominal power to confirm proper operation of all systems. The dynamometer enables accurate monitoring of oil pressure, operating temperatures, engine power, and response to load, which is a unique advantage of our service in Poland.

Post-Overhaul Engine Maintenance

The engine is covered by a full warranty after overhaul. We recommend the first filter replacement after 50 mth of operation and a detailed inspection of all connections and accessories. Subsequent inspections should occur every 250 mth, but no less frequently than every 3 months. Our mobile service is available in the Małopolskie Voivodeship and other regions, providing support for additional diagnostics or servicing if needed.

Machines Equipped with This Engine

The D924 TI-E A4 engine is used in :contentReference[oaicite:1]{index=1} mobile cranes and other models in this series, commonly employed in industrial construction, assembly work, and logistics. Its robust design ensures reliable performance in challenging conditions.