Mobile Welding • Heavy Equipment Repairs • Machinery Fabrication • On-Site Problem Solving
When an excavator attachment system fails, downtime can quickly become expensive. TULGA Mobile Welding Services was called to assist with a damaged excavator quick-hitch mechanism that required more than a straightforward weld repair. The internal spring and hydraulic latch assembly had been dismantled and needed to be carefully compressed, aligned, reassembled and installed back into the excavator coupler. Rather than removing the entire system and sending it away for workshop repair, TULGA carried out the work on site.
The excavator's quick-hitch mechanism contained a heavy internal spring operating together with the hydraulic locking system. The assembly could not simply be pushed back together by hand. The spring needed to be compressed sufficiently for the shaft, hydraulic latch components and surrounding mechanism to be correctly aligned and reassembled. With the excavator unable to operate normally, the objective was clear: develop a practical on-site solution and return the machine to service.
After inspecting the dismantled components, TULGA developed a temporary compression and assembly fixture using heavy threaded rod and fabricated steel components. The fixture allowed controlled compression of the spring while the mechanism was progressively aligned. The main shaft measured approximately 45 mm in diameter, requiring substantial force during the assembly process. Compression was performed gradually while checking component alignment throughout the procedure. Once sufficient compression had been achieved, the hydraulic latch mechanism could be correctly positioned and the quick-hitch assembly rebuilt.
Browse the photos below to see the excavator quick-hitch spring mechanism repair, on-site fabrication, reassembly and final installation completed by TULGA Mobile Welding Services.
One of the key challenges was that there was no ready-made tool available on site for compressing the spring assembly. A temporary threaded-rod fixture was therefore fabricated specifically for the task. This allowed the spring mechanism to be compressed incrementally while maintaining access to the components being assembled. The compression process alone required approximately 34 minutes of controlled tightening and adjustment. This type of repair demonstrates why mobile machinery work often requires more than welding alone. It requires fabrication, mechanical understanding and the ability to develop a workable solution around the machine in front of you.
Where welding was required during the repair process, the components were prepared to achieve strong penetration and minimise contamination and porosity. The repair involved working with substantial steel components associated with the quick-hitch mechanism. Appropriate welding consumables were selected for the repair, with particular attention given to achieving a strong, reliable weld suitable for the mechanical loading involved.
Once the spring had been compressed sufficiently, the internal mechanism was progressively reassembled. The process included:
After mechanical reassembly, the hydraulic connections were restored and the quick-hitch mechanism was operated through its normal movement. The assembly was checked to ensure that the latch mechanism operated correctly and that the repaired system functioned as intended. The excavator was subsequently returned to operation.
The completed repair restored the excavator quick-hitch mechanism and returned the machine to working condition. For the operator, the most important result was simple: the excavator could go back to work. The job also demonstrated the value of having a mobile welder who can approach machinery repairs as a complete mechanical and fabrication problem rather than treating every job as simply another weld.
TULGA Mobile Welding Services provides on-site welding and fabrication support for excavators and other earthmoving equipment throughout Sydney. Typical machinery repair work may include:
Excavator buckets and attachments operate under substantial impact, abrasion and cyclic loading. Cracks commonly develop around:
Transporting damaged machinery or attachments to a fabrication workshop can introduce additional downtime, transport costs and scheduling delays. Mobile repair allows many problems to be addressed where the equipment is already located. For excavation contractors, landscapers, demolition contractors, civil operators and machinery owners, that can mean getting equipment back into service sooner. TULGA Mobile Welding Services brings welding and fabrication equipment directly to the job site.
Not every machinery repair comes with a workshop manual or a purpose-built tool. Sometimes the repair requires a solution to be designed around the problem. The excavator quick-hitch repair shown on this page is a good example. A temporary assembly fixture had to be fabricated before the actual mechanism could even be reassembled. That combination of welding, fabrication and mechanical problem solving is a major part of mobile machinery repair.
If you have an excavator, bucket, quick hitch, attachment or other piece of machinery requiring welding or fabrication, contact TULGA Mobile Welding Services. Photos of the damaged area are extremely helpful when requesting an initial assessment. Send through:
Mobile Welding • Excavator Repairs • Machinery Repairs • Heavy Fabrication • Sydney
For urgent machinery repairs, contact TULGA Mobile Welding Services to discuss the job.
